Komatsumotor grader(no series)
Komatsu GD623A-1(S/N 30001-UP)
Maintenance schedule, common problems & OEM parts breakdown
The Komatsu GD623A-1 (S/N 30001-up) is a mid-size articulated motor grader from Komatsu's GD600-series lineup, built around the mechanical, pre-electronic Komatsu 6D125-1 six-cylinder diesel rated 116 kW (155.6 hp) at 2200 rpm. Operating weight runs around 12,700 kg (27,999 lb), with an 8.50 m overall length, 6.00 m wheelbase, and a 3.72 m x 645 mm moldboard. Drive runs through a 6-speed powershift transmission to a rigid rear tandem bogie, with front-wheel lean steering and an articulated frame for grading precision. It shares its engine and driveline architecture with siblings across the GD611A-1, GD621A-1, GD622A-1, GD625A-1, and GD661A-1 family. No confirmed successor or predecessor model number is documented for this specific S/N range.
Within the 30001-up production run, Komatsu made minor running-change updates starting around S/N 30095, affecting the steering wheel and tandem drive gear and chain hardware, typical mid-production parts revisions rather than a new model designation. A separate B1001-up serial series covered Japan-domestic market units and falls outside this export range. The GD623A-1 sits in Komatsu's transition-era grader generation, built before electronic engine controls and onboard diagnostics became standard, so service and troubleshooting rely on mechanical inspection rather than fault-code scanning. That mechanical simplicity keeps this grader active in the used equipment and parts market today: its 6D125-1 engine and powershift driveline are straightforward to service and rebuild in the field, sustaining steady demand for driveline, tandem, and moldboard wear components well after the model left production.
Below: full specifications, fluids & capacities, the factory service schedule, common service parts, verified fault codes, what owners discuss, attachment guidance, the complete assembly directory, and a serial-number reference. Complete parts lists with full OEM part numbers, exploded diagrams, quantities, and fitment data are available free in Heavy Parts AI.
Komatsu GD623A-1(S/N 30001-UP) specifications
Engine
| Engine model | Komatsu 6D125(-1), 6-cylinder diesel |
| Displacement | 11.05-11.1 L (674.4 cu in), 125 mm bore |
| Rated power | 155.6 hp (116 kW) at 2200 rpm, gear 5-6 (net rating as published) |
| Emissions tier | Not documented for this serial range; mechanical fuel-system engine, no factory tier certification published in available spec sheets |
Weights
| Operating weight | 12,700 kg (27,998.8 lb) |
| Shipping weight / ground pressure | Not published in available spec sheets - verify with dealer |
Dimensions
| Overall length | 8.50 m (27.9 ft) |
| Width over tires | 2.40-2.41 m (7.86-7.90 ft) |
| Height to cab top | 3.49-3.51 m (11.44-11.50 ft) |
| Wheelbase | 6.00 m (19.69-19.70 ft) |
| Rear ground clearance | 0.355-0.37 m (1.17-1.20 ft) |
| Blade base | 2.60-2.62 m (8.54-8.60 ft) |
| Moldboard width | 3.72 m (12.2 ft) |
| Moldboard height | 645 mm (25.4 in) |
| Turning radius | 6.9 m (22.7 ft) |
| Tire size | 13.00-24, 10PR |
Performance
| Forward gears | 6-speed powershift |
| Max forward speed | 46.5 km/h (28.9 mph) |
| Max reverse speed | 56.7-56.8 km/h (35.3 mph) |
| Gradeability | Not published in available spec sheets |
Service capacities (summary)
| Fuel tank | 285 L (75.3 US gal) |
| Hydraulic system | Not published in available spec sheets - verify with dealer |
| Engine oil | Not published in available spec sheets - verify with dealer |
| Cooling system | Not published in available spec sheets - verify with dealer |
Values vary by configuration, region, and serial range — confirm against your machine before planning transport or lifts.
GD623A-1(S/N 30001-UP) fluids & capacities
| System | Capacity | Recommended fluid |
|---|---|---|
| Engine crankcase (with filter) - 6D125-1 diesel | Not confirmed for this serial range in accessible public documentation - check the service refill chart on the machine or with a dealer before draining/refilling | Komatsu Genuine EO (engine oil): SAE 15W-40 for normal/temperate climates, SAE 10W-30 in cold climates, SAE 30 in consistently warm climates. API CF/CF-4 diesel service oil accepted as cross-spec. |
| Cooling system (radiator + block) | Not confirmed for this serial range in accessible public documentation - varies with radiator configuration | Komatsu Super Coolant (AF-ACL), extended-life, anti-corrosion, all-season type, mixed 50/50 with clean water for year-round use. |
| Fuel tank | 285 L (75.3 US gal) | No. 2-D diesel fuel; use No. 1-D or winter-blend diesel below freezing to prevent gelling. |
| Transmission (powershift case) | Not confirmed for this serial range in accessible public documentation | Komatsu Genuine TO (transmission/powertrain oil), viscosity graded to ambient temperature per the machine's fuel/coolant/lubricant chart - typically TO10 to TO30 range across climate bands. |
| Final drive, each side (2x) | Not confirmed for this serial range in accessible public documentation | Komatsu Genuine TO or AXO gear oil, viscosity selected by climate band per the OMM chart. |
| Circle drive / bevel gear case | Not confirmed for this serial range in accessible public documentation | Komatsu Genuine TO gear oil, same climate-graded viscosity as final drives. |
| Hydraulic tank / system (blade, circle, steering, articulation circuits) | Not confirmed for this serial range in accessible public documentation | Komatsu Genuine HO (hydraulic oil), viscosity graded to ambient temperature - lighter grade for cold-climate start-up, heavier grade for sustained high ambient temperatures. |
| Grease points (circle turntable, articulation, linkages, pins/bushings) - spec only | Per grease fitting, no bulk refill volume | Komatsu Genuine multipurpose lithium-based EP grease (NLGI 2); molybdenum-disulfide-fortified grease recommended for the circle turntable and other high-load sliding/rotating points where specified. |
Capacities are refill values from factory literature — always fill to the dipstick/sight gauge, not the number.
Komatsu GD623A-1(S/N 30001-UP) maintenance schedule
| Service interval | Tasks |
|---|---|
| Every 50 h |
|
| Every 250 h |
|
| Every 500 h |
|
| Every 1,000 h |
|
| Every 2,000 h |
|
| Every 4,000 h |
|
Servicing the GD623A-1(S/N 30001-UP) beyond the schedule
Predictive Maintenance & Fluid Analysis
The 6D125-1 predates electronic diagnostics, so wear trending relies on lab oil analysis rather than fault codes. Pull scheduled samples from the engine, powershift transmission, tandem cases, and final drives to catch bearing and gear wear early. Because the mechanical injection pump is sensitive to water and dirt, drain the fuel/water separator often and lab-test fuel quality. Track coolant condition and hydraulic fluid cleanliness too, since this grader has no onboard sensors to flag contamination before it damages the fuel system or blade hydraulics.
Corrective & Common Repairs
Common wear points center on the circle and drawbar assembly, moldboard mounting shoes, and the tandem case drive chains and gears, especially on early-build units below S/N 30095 that predate Komatsu's running-change hardware. Expect steering linkage looseness and wheel-lean cylinder seal leaks as recurring corrective jobs. On the powershift transmission, clutch pack slippage and modulation valve wear are the usual repair triggers. Because the 6D125-1 has no ECM, driveability issues are chased mechanically through injection pump timing, governor linkage, and fuel delivery, not scan-tool codes.
Overhaul & Rebuild Points
Major rebuild points include the circle turntable and wear shoes, tandem case gear trains, and final drive housings, all of which see heavy loading from grading and blade side-shift work. Engine overhauls on the mechanical 6D125-1 center on the injection pump, cylinder liners, and valve train rather than sensor or ECM replacement. Transmission rebuilds typically address clutch pack and modulation hardware wear from repeated shifting under load. Inspect the articulation hitch and frame for fatigue cracking before undertaking any major driveline rebuild.
Seasonal & Environment Servicing
In cold climates, the mechanical 6D125-1 needs correct-viscosity oil and a working cold-start aid before start-up, since there is no electronic idle management to protect the engine. In hot, dusty environments, clean the radiator core and oil cooler fins often and service the air filter primary and safety elements more frequently to protect the mechanical injection pump from abrasive intake dirt. Before winter, drain water from the fuel tank and separator to prevent injection pump icing and corrosion in the plunger-type pump.
GD623A-1(S/N 30001-UP) common service parts
| Part number | Part | Notes | |
|---|---|---|---|
| 600-311-8291 | Cartridge,Fuel Filter | Fuel system service | Check fitment → |
| 09019-08035 | Wrench,Filter (For Add. Fuel Filter) | Fuel system service | Check fitment → |
| 232-843-1430 | Filter Ass'Y,Air | Air intake service | Check fitment → |
| 07000-02080 | O-Ring,Hydraulic Oil Filter | Hydraulic service | Check fitment → |
| 07000-02075 | O-Ring,Steering Oil Filter | Lubrication service | Check fitment → |
Always confirm against your machine's serial number — cross-check any part in Heavy Parts AI before ordering.
GD623A-1(S/N 30001-UP) fault codes & troubleshooting
| Code | Meaning | Likely cause | What to do |
|---|---|---|---|
| Engine Oil Pressure lamp (icon, no alphanumeric code) | Engine oil pressure has dropped below the safe operating threshold | Low oil level, clogged oil filter, worn oil pump, or oil pressure switch fault | Stop the engine immediately, check oil level and filter condition before restarting |
| Coolant Temperature lamp / high-temp gauge reading (icon, no alphanumeric code) | Engine coolant temperature has exceeded the normal operating range | Low coolant level, blocked radiator core, slipping or broken fan belt, or stuck thermostat | Reduce load and idle the engine down, check coolant level and radiator fins once safely cooled; do not open a hot cap |
| Battery Charge (alternator) lamp (icon, no alphanumeric code) | Alternator is not charging the battery circuit | Loose or broken fan/alternator belt, faulty alternator, or wiring/connection fault | Check belt tension and condition, then test the charging circuit output |
| Air Cleaner Restriction indicator (icon, no alphanumeric code) | Intake air filter element is restricted | Dust-loaded or clogged air filter element | Inspect and clean or replace the air filter element |
| Parking Brake indicator lamp (icon, no alphanumeric code) | Parking brake is applied or brake system pressure is low | Parking brake left engaged, or low hydraulic pressure to the brake circuit | Confirm parking brake release and check brake system pressure if lamp stays lit with brake released |
| Torque Converter / Power-train Oil Temperature gauge high reading (icon, no alphanumeric code) | Torque converter or transmission oil is overheating | Low oil level, sustained overload, or clogged oil cooler | Reduce work load, let the unit idle to cool, then check oil level and cooler for blockage |
Codes and remedies are general guidance for this model family — always confirm with diagnostic tooling and your dealer before major repairs.
GD623A-1(S/N 30001-UP) attachments & work tools
Moldboard / grading blade
Standard moldboard is about 3.7 m (12'2") wide by roughly 645 mm (25.4 in) tall, with a bolt-on replaceable cutting edge and end bits. It rides on the circle and is positioned by hydraulic tilt, side-shift and circle-rotation cylinders operated from the cab, not a tool-less coupler.
Front/mid-mount scarifier
Shank-type scarifier for breaking up hard or frozen surfaces ahead of grading, controlled by a dedicated hydraulic lift lever/circuit built into the machine. Shank-rack size is not documented for this exact serial range; graders in this weight class commonly use multi-shank racks in the 9-11 position range, so confirm shank count with your dealer.
Rear-mounted ripper/scarifier
Rear frame-mounted shank assembly for ripping, typically offered as a low-shank-count ripper (a few heavy shanks) or a higher-count scarifier rack for surface work; a pusher/mounting plate and a rear hydraulic circuit are needed to run it. Exact shank counts for this model vary by configuration.
Snow removal attachments (V-plow, snow wing, windrow eliminator)
Motor graders in this class can be fitted with a front V-plow or a side-mounted, hydraulically angled snow wing for winter clearing work, plus windrow-eliminator style attachments. These are standard optional work tools for the grader class generally; a factory listing tied specifically to this serial range was not found, so verify current availability with your dealer.
Circle/drawbar mounting and hydraulic control system
Work tools mount to the factory circle-drawbar frame using pinned or bolted brackets rather than a skid-steer-style quick coupler. Blade and attachment movement (tilt, shift, lift, circle rotation) is run through cab-controlled hydraulic cylinders, and add-on tools such as the scarifier draw on the machine's own hydraulic circuit.
Engine and factory configuration options
This machine uses a Komatsu 6D125 six-cylinder diesel, the same engine family shared across other graders in the GD605A-GD663A size range, delivering roughly 116 kW (155.6 hp) at 2200 rpm with an operating weight near 12.7 t (about 28,000 lb). Factory configuration options in this class typically include an enclosed ROPS/FOPS cab versus open canopy and articulated-frame hydraulic offset steering; specific option availability for S/N 30001-UP should be confirmed with the dealer parts book.
All GD623A-1(S/N 30001-UP) assemblies by section
Every catalogued assembly group for the Komatsu GD623A-1(S/N 30001-UP). Open an assembly to preview the parts inside — full OEM part numbers are available in Heavy Parts AI.
6d125-1z Engine S/N 19761-Up
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Air Cleaner And Mounting (High Altitude Spec.)
| 01***40 | Bolt,(Dust And Dirt Protection) | 2 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 6 |
| 01***08 | Nut,(For Straight Tilt Dozer) (D65p) | 6 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Air Cleaner And Mounting(#19761-26169)
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 2 |
| 01***08 | Nut,(For Straight Tilt Dozer) (D65p) | 6 |
| 01***16 | Washer,Radio Controlled Slag Handling | 6 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Air Cleaner And Mounting(#26170-)
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 4 |
| 01***40 | Bolt, Mount Master Brake Cylinder | 1 |
| 01***08 | Nut,(For Straight Tilt Dozer) (D65p) | 6 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Air Compressor (With Air Compressor)(#.-)
| 61***11 | Air Compressor Ass'Y,(See Fig.0711a) | 1 |
| DK***20 | Connecting Rod A | 1 |
| DK***90 | Washer,Air Compressor | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Air Compressor (With Air Compressor)(#19761-.)
| 61***10 | Air Compressor Ass'Y,(See Fig.0711) | 1 |
| DK***20 | Connecting Rod A | 1 |
| DK***90 | Washer,Air Compressor | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Air Compressor And Piping (With Air Compressor)
| 07***12 | Gasket,(Without Air Compressor Type) (K2) | 4 |
| 07***12 | Gasket,(Without Air Compressor Type) (K1) | 8 |
| 07***16 | Gasket,Air Compressor Piping | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Air Intake Manifold And Connection (High Altitude Spec.)
| 01***10 | Bolt,(With Auto Emergency Steering) | 2 |
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 14 |
| 01***55 | Bolt, Mount Tube To Switch Pump | 5 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Air Intake Manifold And Mounting
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 16 |
| 01***55 | Bolt, Mount Tube To Switch Pump | 5 |
| 01***60 | Bolt, Mount Tube To Switch Pump | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Alternator (25a)
| 60***50 | Alternator A. (25a),(With Non Hardening Pulley) | 1 |
| KD***57 | Bearing,Ball? Front | 1 |
| KD***70 | Bracket,Front | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Alternator (25a) (Sandy And Dusty Spec.)
| 60***40 | Alternator A. (25a),(With Hardening Pulley) | 1 |
| KD***57 | Bearing,Ball? Front | 1 |
| KD***80 | Collar | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Alternator (35a) (With Hardening Pulley)
| 60***20 | Alternator A. (35a),(With Hardening Pulley) | 1 |
| KD***57 | Bearing,Ball? Front | 1 |
| KD***80 | Collar | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Alternator (35a) (With Non Hardening Pulley)
| 60***60 | Alternator A. (35a),(With Non Hardening Pulley) | 1 |
| KD***57 | Bearing,Ball? Front | 1 |
| KD***80 | Collar | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Alternator (50a)
| 60***30 | Alternator A. (50a),(With Non Hardening Pulley) | 1 |
| SD***X0 | Pulley,Non Hardening | 1 |
| SD***X0 | Coil Assembly | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Alternator And Mounting (25a)
| 01***75 | Bolt,(For Adjusting) | 1 |
| 01***30 | Bolt | 1 |
| 01***11 | Nut (Welded) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Alternator And Mounting (35a)
| 01***90 | Bolt, Fan Mounting | 1 |
| 01***30 | Bolt | 1 |
| 01***23 | Washer,(A)(W/After Cooler)(S6d155-4b) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Alternator And Mounting (50a)
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 1 |
| 01***30 | Bolt | 1 |
| 01***23 | Washer,(A)(W/After Cooler)(S6d155-4b) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Alternator Nad Mounting (25a) (Sandy And Dusty Spec.)
| 01***90 | Bolt, Fan Mounting | 1 |
| 01***30 | Bolt | 1 |
| 01***23 | Washer,(A)(W/After Cooler)(S6d155-4b) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Camshaft
| 01***22 | Bolt | 2 |
| 04***25 | Key, Plain Woodruff | 1 |
| 04***12 | Ring,Snap (For Ripper) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Cooling Fan And Mounting
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 22 |
| 01***40 | Bolt, Mount Master Brake Cylinder | 2 |
| 01***95 | Bolt,(For 2nd Travel Speed) (Op) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Cooling Fan And Mounting (Suction Fan Type)
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 16 |
| 01***40 | Bolt, Mount Master Brake Cylinder | 2 |
| 01***50 | Bolt,(With Service Valve R.H.) | 6 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Corrosion Resistor And Piping
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 5 |
| 01***08 | Nut,(For Canvas Canopy?Head Guard) | 1 |
| 02***25 | Bolt,(Cold Weather Spec.) | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Crankshaft
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 6 |
| 01***30 | Screw | 1 |
| 01***35 | Screw | 5 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Cylinder Block
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 1 |
| 01***12 | Bolt,(Without Air Compressor Type) | 3 |
| 01***16 | Washer,Radio Controlled Slag Handling | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Cylinder Block Cover(#19761-26169)
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 2 |
| 01***00 | Bolt, Mount Back-Up Alarm | 2 |
| 01***08 | Nut,(For Canvas Canopy?Head Guard) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Cylinder Block Cover(#26170-)
| 07***20 | Clamp, Spring Hose | 1 |
| 07***63 | Hose | 1 |
| 61***90 | O-Ring,Breather | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Cylinder Head(#19761-27127)
| 04***20 | Pin,Dowel (Welded) | 2 |
| 61***30 | Sleeve,Holder | 1 |
| 61***20 | Cotter, Valve | 48 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Cylinder Head(#27128-)
| 04***20 | Pin,Dowel (Welded) | 2 |
| 61***30 | Sleeve,Holder | 1 |
| 61***20 | Cotter, Valve | 48 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Exhaust Manifold
| 01***80 | Bolt, Mount Strainer Flange | 18 |
| 07***08 | Plug,(Without Auto Priming System) | 1 |
| 61***20 | Spacer,(For Shipping) | 18 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Exhaust Manifold And Turbochager (High Altitude Spec.)
| 01***80 | Bolt, Mount Strainer Flange | 2 |
| 01***00 | Bolt (M10-1.50x100) | 16 |
| 01***45 | Screw | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Flywheel And Flywheel Housing(#19761-26169)
| 01***45 | Bolt,(For Suction? Reversible Fan) | 1 |
| 01***50 | Bolt, Radiator To Frame | 6 |
| 01***60 | Bolt, Hanger Bearing Mounting | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Flywheel And Flywheel Housing(#26170-)
| 01***45 | Bolt,(For Suction? Reversible Fan) | 1 |
| 01***50 | Bolt, Radiator To Frame | 6 |
| 01***60 | Bolt, Hanger Bearing Mounting | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Front Cover And Front Support
| 01***25 | Bolt,(Without Auto Priming System) | 6 |
| 01***60 | Screw | 1 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Front Cover And Front Support (With Air Compressor)
| 01***25 | Bolt,(Without Auto Priming System) | 6 |
| 01***60 | Screw | 1 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Fuel Filter And Piping
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 4 |
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
| 01***16 | Washer,Radio Controlled Slag Handling | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Fuel Injection Pum Pand Piping
| 01***75 | Bolt,(See Fig.0142) | 4 |
| 01***30 | Bolt | 4 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Fuel Injection Pump (Coupling) (With Air Compressor)
| ND***50 | Bolt | 1 |
| ND***40 | Bolt | 2 |
| ND***61 | Bolt | 6 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Fuel Injection Pump (Coupling)(#26170-)
| ND***30 | Block,Coupling | 1 |
| ND***10 | Flange,Coupling | 1 |
| ND***50 | Bolt | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Fuel Injection Pump (Feed Pump) (With Air Compressor)
| ND***61 | Feed Pump Ass'Y | 1 |
| ND***40 | Washer? 1mm,Plate | 1 |
| ND***70 | Washer,Union | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Fuel Injection Pump (Feed Pump)(#21670-)
| ND***40 | Washer? 1mm,Plate | 1 |
| ND***70 | Washer,Union | 4 |
| ND***10 | Spring, Check Valve | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Fuel Injection Pump (Governor) (1/2) (With Air Compressor)
| ND***40 | Plate,Thrust | 1 |
| ND***10 | Governor Ass'Y | 1 |
| ND***40 | Plug,Screw | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Fuel Injection Pump (Governor) (1/2)(#26170-)
| ND***40 | Plate,Thrust | 1 |
| ND***40 | Plug,Screw | 1 |
| ND***80 | Gasket | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Fuel Injection Pump (Governor) (2/2) (With Air Compressor)
| ND***20 | Washer? 1.0mm,Cover Plate | 2 |
| ND***30 | Lever,Adjusting | 1 |
| ND***40 | O-Ring | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Fuel Injection Pump (Governor) (2/2)(#26170-)
| ND***20 | Washer? 1.0mm,Cover Plate | 2 |
| ND***30 | Lever,Adjusting | 1 |
| ND***90 | Seal,Oil | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Fuel Injection Pump (Pump) (With Air Compressor)
| 61***70 | Injection Pump A | 1 |
| ND***50 | Ring,Adjust | 1 |
| ND***80 | O-Ring | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Fuel Injection Pump (Pump)(#26170-)
| 61***20 | Injection Pump A | 1 |
| 61***21 | Injection Pump A | 1 |
| ND***30 | Sleeve,Control | 6 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Fuel Injection Pump And Piping (With Air Compressor)
| 01***75 | Bolt,(See Fig.0142) | 4 |
| 01***30 | Bolt | 1 |
| 01***45 | Bolt,(For Power Tilt Mech Angle) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Fuel Nozzle And Spill Pipe
| 01***45 | Bolt, Divider Valve Mounting | 12 |
| 07***65 | O-Ring,Cylinder Block | 6 |
| 07***12 | Gasket,Mechanical Pump Piping | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Gasket Kit
| 02***43 | O-Ring,Water Manifold | 6 |
| 07***15 | O-Ring,(For Low Speed) (D40pf) | 1 |
| 07***25 | O-Ring,Injection Pump Mounting | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Heater Switch And Heater Signal
| 08***19 | Cap, At Heater Relay Terminals | 2 |
| 60***70 | Switch,Air Intake Heater | 1 |
| 60***30 | Signal,Engine Pre Heater | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Lubricating Oil Cooler
| 01***25 | Bolt,Without Revolution Sensor | 2 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 13 |
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Lubricating Oil Filter And Mounting
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 8 |
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
| 01***35 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Lubricating Oil Piping(#19761-26169)
| 01***60 | Bolt, Mount Tube To Switch Pump | 2 |
| 01***16 | Washer,Radio Controlled Slag Handling | 7 |
| 04***12 | Ring, Snap | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Lubricating Oil Piping(#26170-)
| 01***60 | Bolt, Mount Tube To Switch Pump | 2 |
| 01***16 | Washer,Radio Controlled Slag Handling | 7 |
| 04***12 | Ring, Snap | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Lubricating Oil Pump And Suction Pipe
| 01***25 | Bolt,(Without Auto Priming System) | 4 |
| 01***20 | Bolt,(Large Capacity Type) (Std) | 2 |
| 01***25 | Bolt,(Sandy? Dusty Terrain Spec.) | 5 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Muffler And Mounting
| 01***25 | Bolt,(Sandy? Dusty Terrain Spec.) | 4 |
| 01***40 | Bolt,(Dust And Dirt Protection) | 4 |
| 01***30 | Bolt, Mount Pump | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Muffler And Mounting (High Altitude Spec.)
| 01***40 | Bolt,(Dust And Dirt Protection) | 4 |
| 01***55 | Bolt,(For Suction? Reversible Fan) | 4 |
| 01***30 | Bolt,Radio Controlled Slag Handling | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Oil Pan
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 31 |
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 7 |
| 01***16 | Washer,Radio Controlled Slag Handling | 37 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Oil Pan (Cold Terrain Spec.)(#19761-44190)
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 2 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 31 |
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 7 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Oil Pan (Cold Terrain Spec.)(#44191-)
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 2 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 29 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Piston And Connecting Rod
| 02***13 | Pin, Dowel | 2 |
| 04***18 | Ring, Snap | 12 |
| 61***32 | Piston Ring Ass'Y | 6 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Rocker Arm And Housing
| 01***08 | Nut,R.H. Thread | 12 |
| 01***16 | Washer,Radio Controlled Slag Handling | 42 |
| 61***10 | Housing, Rocker Lever | 6 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Rocker Arm Housing Cover
| 01***16 | Washer,Radio Controlled Slag Handling | 24 |
| 61***11 | Cover,Head? No.2?3?4?5?6 | 6 |
| 61***10 | Gasket,Cylinder Head Cover | 6 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Starting Motor (7.5kw)
| 60***30 | Starting Motor Ass'Y,(7.5kw) | 1 |
| KD***20 | Magnetic Switch Assembly | 1 |
| KD***40 | Spring,Spring | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Starting Motor And Mounting (7.5kw? 11kw)
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 1 |
| 01***40 | Bolt,(With Center Guard) | 3 |
| 08***19 | Band,(Without Air Conditioner) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Turbocharger (High Altitude Spec.)
| 61***00 | Turbocharger Ass'Y,(Tv7705) | 1 |
| GA***85 | V-Band Ass'Y | 1 |
| GA***85 | V-Band | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Turbocharger Lubricating Oil Piping (High Altitude Spec.)
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 5 |
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
| 01***08 | Nut,(For Canvas Canopy?Head Guard) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Water Manifold And Thermostat(#19761-26169)
| 02***43 | O-Ring,Water Manifold | 6 |
| 07***12 | Washer, Gasket,(Without Thermo Sensor) (K1) | 1 |
| 07***08 | Plug,(Without Auto Priming System) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Water Manifold And Thermostat(#26170-)
| 02***43 | O-Ring,Water Manifold | 6 |
| 07***12 | Washer, Gasket,(Without Thermo Sensor) (K1) | 1 |
| 07***08 | Plug,(Without Auto Priming System) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Water Pump And Mounting
| 01***30 | Bolt,(For France Noise Suppression) | 2 |
| 01***16 | Bolt (With Air Heater & Conditioner) | 6 |
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 5 |
Komatsu : Gd623a-1(S/N 30001-Up) : 6d125-1z Engine S/N 19761-Up : Water Separator And Mounting
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 2 |
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
| 01***08 | Nut,(For Canvas Canopy?Head Guard) | 2 |
Control System
Komatsu : Gd623a-1(S/N 30001-Up) : Control System : Accelerator Pedal(#30001-30110)
| 01***25 | Bolt,Without Revolution Sensor | 1 |
| 01***30 | Bolt,(Not Used With Emergency Str.) | 3 |
| 01***05 | Nut,L.H. Thread (D31s) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Control System : Accelerator Pedal(#30111-)
| 01***25 | Bolt,Without Revolution Sensor | 1 |
| 01***30 | Bolt,(Not Used With Emergency Str.) | 2 |
| 01***05 | Nut,L.H. Thread (D31s) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Control System : Bank Cutting Control System
| 01***16 | Bolt (With Air Heater & Conditioner) | 4 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 1 |
| 01***45 | Bolt, Mount Center Hinge Retainer (Upper) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Control System : Booster And Master Cylinder
| 04***30 | Seal, Dust | 1 |
| 23***70 | Seat | 1 |
| 23***20 | Spring | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Control System : Brake Pedal (For Wet Type Disc Brake)
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 4 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 4 |
| 01***30 | Bolt,(Not Used With Emergency Str.) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Control System : Brake Pedal(#30001-30218)
| 01***12 | Bolt,(With Cylinder Cover) | 2 |
| 01***35 | Bolt,(For Quick Shift) (Mitsubishi) | 1 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 8 |
Komatsu : Gd623a-1(S/N 30001-Up) : Control System : Brake Pedal(#30219-)
| 01***12 | Bolt,(With Cylinder Cover) | 2 |
| 01***35 | Bolt,(For Quick Shift) (Mitsubishi) | 1 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Control System : Brake Piping
| 01***16 | Bolt (With Air Heater & Conditioner) | 2 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 2 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 8 |
Komatsu : Gd623a-1(S/N 30001-Up) : Control System : Brake Piping (1/4) (For Wet Type Disc Brake)
| 01***75 | Bolt,(For Shipping) | 2 |
| 01***25 | Washer,Spring?For Additional Rear Lam | 2 |
| 07***34 | O-Ring,(For 2-Actuater Attachment) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Control System : Brake Piping (2/4) (For Wet Type Disc Brake)
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 6 |
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 4 |
| 01***30 | Bolt,(Not Used With Emergency Str.) | 8 |
Komatsu : Gd623a-1(S/N 30001-Up) : Control System : Brake Piping (3/4) (For Wet Type Disc Brake)
| 01***16 | Bolt (With Air Heater & Conditioner) | 4 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 6 |
| 01***25 | Washer,Spring?For Additional Rear Lam | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Control System : Brake Piping (4/4) (For Wet Type Disc Brake)
Komatsu : Gd623a-1(S/N 30001-Up) : Control System : Console Box
| 01***16 | Bolt, Mount Washer Tank To Bracket, Bolt | 2 |
| 01***20 | Bolt,(With Auto Emergency Steering) | 6 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 6 |
Komatsu : Gd623a-1(S/N 30001-Up) : Control System : Fuel Control Lever(#30001-30263)
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 2 |
| 01***05 | Nut,L.H. Thread (D31s) | 1 |
| 01***06 | Nut,(With Back-Up Alarm) (Op), Nut; Was 01580-10806 | 3 |
Komatsu : Gd623a-1(S/N 30001-Up) : Control System : Fuel Control Lever(#30264-)
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 2 |
| 01***05 | Nut,L.H. Thread (D31s) | 1 |
| 01***06 | Nut,(With Back-Up Alarm) (Op), Nut; Was 01580-10806 | 3 |
Komatsu : Gd623a-1(S/N 30001-Up) : Control System : Hydraulic Control Lever L.H.
| 01***16 | Screw | 1 |
| 01***05 | Nut,L.H. Thread (D31s) | 3 |
| 01***06 | Nut,(With Back-Up Alarm) (Op), Nut; Was 01580-10806 | 3 |
Komatsu : Gd623a-1(S/N 30001-Up) : Control System : Hydraulic Control Lever R.H.
| 01***16 | Screw | 1 |
| 01***05 | Nut,L.H. Thread (D31s) | 4 |
| 01***06 | Nut,(With Back-Up Alarm) (Op), Nut; Was 01580-10806 | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Control System : Inching Pedal
| 01***30 | Bolt,(For Mechanical Governor) | 2 |
| 01***20 | Bolt,(Without Rops Guard? Canopy) | 4 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Control System : Parking Brake Control Lever
Komatsu : Gd623a-1(S/N 30001-Up) : Control System : Steering Wheel(#30001-30094)
| 01***11 | Nut - Mounting | 1 |
| 01***26 | Washer,(For Additional Rear Lamp) | 1 |
| 01***32 | Washer,(With Auto Emergency Steering) | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Control System : Steering Wheel(#30095-)
| 01***11 | Nut - Mounting | 1 |
| 01***07 | Washer, Spring | 1 |
| 01***26 | Washer,(For Additional Rear Lamp) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Control System : Tire Inflation
| 01***16 | Bolt (With Air Heater & Conditioner) | 1 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 4 |
| 01***25 | Washer,Spring?For Additional Rear Lam | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Control System : Transmission Control Lever(#30001-30106)
| 01***12 | Bolt, Bolt,(No Need To Quick Shift) | 8 |
| 01***16 | Bolt, Mount Washer Tank To Bracket, Bolt | 4 |
| 01***30 | Bolt,(For Mechanical Governor) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Control System : Transmission Control Lever(#30107-)
| 01***16 | Bolt, Mount Washer Tank To Bracket, Bolt | 4 |
| 01***30 | Bolt,(For Mechanical Governor) | 2 |
| 01***30 | Bolt,(Not Used With Emergency Str.) | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Control System : Transmission Control Linkage
| 01***55 | Bolt, Mount Tube To Switch Pump | 2 |
| 01***06 | Nut? L.H. Thread,L.H. Thread (For Chinese) | 3 |
| 01***06 | Nut,L.H. Thread (For Russian) | 3 |
Engine Related Parts And Electrical System
Komatsu : Gd623a-1(S/N 30001-Up) : Engine Related Parts And Electrical System : Additional Horn
| 01***14 | Bolt,(With Canopy) | 2 |
| 01***18 | Bolt | 2 |
| 01***25 | Washer,Spring?For Additional Rear Lam | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Engine Related Parts And Electrical System : Back-Up Alarm
| 01***16 | Bolt, Mount Washer Tank To Bracket, Bolt | 2 |
| 01***14 | Bolt,(With Canopy) | 1 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Engine Related Parts And Electrical System : Back-Up Lamp
| 01***16 | Bolt, Mount Washer Tank To Bracket, Bolt | 2 |
| 01***23 | Washer,(With Auto Emergency Steering) | 4 |
| 08***08 | Grommet,(Without Beacon Lamp) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Engine Related Parts And Electrical System : Battery
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 8 |
| 01***08 | Nut,(For Canvas Canopy?Head Guard) | 16 |
| 01***32 | Washer,(With Auto Emergency Steering) | 16 |
Komatsu : Gd623a-1(S/N 30001-Up) : Engine Related Parts And Electrical System : Battery (Extreme Cold Terrain Spec.)
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 8 |
| 01***08 | Nut,(For Canvas Canopy?Head Guard) | 16 |
| 01***32 | Washer,(With Auto Emergency Steering) | 16 |
Komatsu : Gd623a-1(S/N 30001-Up) : Engine Related Parts And Electrical System : Combination Lamp
| 01***12 | Bolt, Bolt,(No Need To Quick Shift) | 1 |
| 01***23 | Washer,(With Auto Emergency Steering) | 1 |
| 08***12 | Grommet,(Not Used For Cab Spec.) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Engine Related Parts And Electrical System : Electrical System (Center)
| 01***12 | Bolt, Bolt,(No Need To Quick Shift) | 4 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 2 |
| 01***20 | Screw - Turn Signal And Parkinglight Mounting | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Engine Related Parts And Electrical System : Electrical System (For Differential Lock)
| 01***12 | Bolt, Bolt,(No Need To Quick Shift) | 1 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 1 |
| 01***09 | Seat (Welded) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Engine Related Parts And Electrical System : Electrical System (For Wet Type Disc Brake)
| 23***61 | Sensor,Engine Oil Pressure | 1 |
| 23***20 | Buzzer | 1 |
| 23***80 | Gauge,Air Pressure | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Engine Related Parts And Electrical System : Electrical System (Front)
| 01***12 | Bolt,(With Cylinder Cover) | 1 |
| 01***14 | Bolt,(With Canopy) | 2 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Engine Related Parts And Electrical System : Electrical System (Rear)
| 01***14 | Bolt | 2 |
| 01***20 | Bolt,(With Auto Emergency Steering) | 2 |
| 01***30 | Bolt,(For Mechanical Governor) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Engine Related Parts And Electrical System : Engine And Transmission Mounting Parts
| 01***40 | Bolt,(With Service Valve R.H.) | 12 |
| 01***40 | Bolt,R.H. Outside And L.H. Inside, Bolt | 8 |
| 01***50 | Bolt,(For Tbg/Abe Spec.) | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Engine Related Parts And Electrical System : Engine Oil Heater And Water Heater (Extreme Cold Terrain Spec.)
| 01***10 | Bolt,(With Auto Emergency Steering) | 1 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 1 |
| 01***12 | Screw | 5 |
Komatsu : Gd623a-1(S/N 30001-Up) : Engine Related Parts And Electrical System : Engine Stop Motor(#30264-)
| 01***30 | Bolt | 3 |
| 01***15 | Bolt | 2 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 6 |
Komatsu : Gd623a-1(S/N 30001-Up) : Engine Related Parts And Electrical System : Front Working Lamp
| 01***30 | Bolt-Hex, Bolt,(With Center Guard) | 2 |
| 01***22 | Seat (Welded) | 2 |
| 01***45 | Washer,(For Quick Shift) (Mitsubishi) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Engine Related Parts And Electrical System : Fuel Piping
Komatsu : Gd623a-1(S/N 30001-Up) : Engine Related Parts And Electrical System : Fuel Tank And Hydraulic Tank
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 4 |
| 01***25 | Bolt,(For High High Lift) | 1 |
| 01***50 | Bolt,(For Tbg/Abe Spec.) | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Engine Related Parts And Electrical System : Instrument Panel (Center)
| 01***16 | Screw | 6 |
| 01***12 | Washer,(With Body Positioner) | 6 |
| 08***14 | Clip,(Without Ripper Point Light) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Engine Related Parts And Electrical System : Instrument Panel (Side)
| 01***20 | Bolt,(Without Maintenance Monitor) | 6 |
| 01***20 | Bolt,(Without Rops Guard? Canopy) | 3 |
| 01***12 | Screw,(With Articulate Indicator) | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Engine Related Parts And Electrical System : License Plate Lamp
| 08***10 | Bulb? 12w,(For Japan) | 1 |
| 08***00 | Lamp Ass'Y,License (For Japan) | 1 |
| 23***50 | Wire Ass'Y | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Engine Related Parts And Electrical System : Radiator And Piping(#30001-30110)
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 10 |
| 01***50 | Bolt,(With Service Valve R.H.) | 4 |
| 01***80 | Bolt | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Engine Related Parts And Electrical System : Radiator Piping (Remote Drain Line)
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 1 |
| 01***30 | Washer, Spring (Supplied W/Spider Assembly), Washer-Spring | 1 |
| 07***56 | Hose | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Engine Related Parts And Electrical System : Radiator Piping(#30111-)
| 01***35 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
| 01***50 | Bolt,(With Service Valve R.H.) | 4 |
| 01***75 | Bolt, Mount Main Relief Valve | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Engine Related Parts And Electrical System : Radiator(#30111-)
| 01***20 | Bolt,(With Auto Emergency Steering) | 10 |
| 01***50 | Bolt,(For Strengthened Cover) | 2 |
| 01***45 | Bolt,(For Travel Motor) (Not Show) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Engine Related Parts And Electrical System : Rear Working Lamp
Frame And Guard
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Air Conditinner (2/9) (Condensor And Mounting Parts)
| 01***20 | Bolt, Wiring Harness Mounting Bracket | 8 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 4 |
| 01***25 | Bolt, Pinlock | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Air Conditioner (1/9) (Air Conditioner Unit And Related Parts)
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 11 |
| 01***16 | Bolt? Wing,Wing | 2 |
| 01***10 | Washer,(For 35a Alternator) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Air Conditioner (3/9) (Compressor And Mounting Parts)(#.-)
| 01***85 | Bolt,Spring | 2 |
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 4 |
| 01***30 | Bolt,(Not Used With Emergency Str.) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Air Conditioner (3/9) (Compressor And Mounting Parts)(#30001-.)
| 01***30 | Bolt,(For Mechanical Governor) | 8 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 2 |
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Air Conditioner (4/9) (Cooler Piping)(#3001-)
| 01***20 | Bolt,(Without Maintenance Monitor) | 2 |
| 01***16 | Bolt (With Air Heater & Conditioner) | 2 |
| 01***20 | Bolt,(With Auto Emergency Steering) | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Air Conditioner (5/9) (Heater Piping)
| 01***25 | Bolt,(Rear Attachment Less) | 6 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 3 |
| 01***16 | Seat,(For Desiccant Type) (Welded) | 3 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Air Conditioner (6/9) (Air Piping)
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 2 |
| 01***12 | Screw,(With Articulate Indicator) | 10 |
| 01***20 | Bolt? Wing,(Noise Suppression Spec.) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Air Conditioner (7/9) (Control Panel)
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Air Conditioner (8/9) (Electrlcal Parts)
| 01***12 | Bolt, Bolt,(No Need To Quick Shift) | 4 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 4 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Air Conditioner (9/9) (Air Compressor Inner Parts)
| 20***10 | Air Compressor A. (Kit) | 1 |
| ND***70 | Clamp, Tapping | 1 |
| ND***40 | Compressor Assembly | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Back And Room Mirror
| 01***10 | Bolt,(With Auto Emergency Steering) | 2 |
| 01***20 | Bolt,(With Auto Emergency Steering) | 2 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 6 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Canopy
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 10 |
| 01***30 | Bolt-Hex, Bolt,(With Center Guard) | 8 |
| 01***32 | Bolt | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Car Heater (1/3)
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 7 |
| 01***32 | Washer,(With Auto Emergency Steering) | 7 |
| 07***89 | Clamp,(For Japan) | 12 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Car Heater (1/4)(Extreme Cold Terrain Spec.)
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 7 |
| 01***32 | Washer,(With Auto Emergency Steering) | 7 |
| 07***89 | Clamp,(For Japan) | 12 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Car Heater (2/3)
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 8 |
| 01***12 | Screw,(Additional Sun Visor) | 4 |
| 01***13 | Washer,Spring(For Wiper Switch Earth) | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Car Heater (2/4)(Extreme Cold Terrain Spec.)
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 8 |
| 01***12 | Screw,(Additional Sun Visor) | 4 |
| 01***13 | Washer,Spring(For Wiper Switch Earth) | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Car Heater (3/3)
| 01***12 | Bolt, Bolt,(No Need To Quick Shift) | 2 |
| 01***12 | Bolt,(With Cylinder Cover) | 2 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Car Heater (3/4)(Extreme Cold Terrain Spec.)
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 8 |
| 01***32 | Washer,(With Auto Emergency Steering) | 8 |
| 23***61 | Clip | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Car Heater (4/4)(Extreme Cold Terrain Spec.)
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 1 |
| 01***09 | Seat (Welded) | 1 |
| 01***16 | Seat,(For Desiccant Type) (Welded) | 19 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Caution Lamp (For Cab)
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 4 |
| 01***32 | Washer,(With Auto Emergency Steering) | 4 |
| 08***60 | Bulb? 35w,35w | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Floor Mat
| 23***30 | Mat,Floor | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Frame And Platform (For Wet Type Disc Brake)
| 01***16 | Bolt (With Air Heater & Conditioner) | 2 |
| 01***14 | Seat,(For Automatic) | 4 |
| 01***16 | Seat,(For Desiccant Type) (Welded) | 6 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Front Frame
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 28 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 8 |
| 01***35 | Bolt, Bolt, Mount Tubes To Switch And Work Pumps | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Front Weight
| 01***10 | Bolt (Op) | 6 |
| 01***19 | Nut - M24 | 6 |
| 01***60 | Washer,(Without Rops Guard? Canopy) | 12 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Head Lamp (For Cab)
| 01***20 | Bolt,(With Auto Emergency Steering) | 4 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 4 |
| 01***25 | Washer,Spring?For Additional Rear Lam | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Mirror (Rear)
| 01***25 | Bolt,Without Revolution Sensor | 1 |
| 01***06 | Nut,(With Back-Up Alarm) (Op), Nut; Was 01580-10806 | 1 |
| 01***06 | Nut | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Operator'S Cab (B-Type) (1/5)
| 01***14 | Bolt,(With Canopy) | 8 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 4 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 12 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Operator'S Cab (B-Type) (2/5)
| 01***16 | Bolt, Mount Washer Tank To Bracket, Bolt | 4 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 4 |
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 8 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Operator'S Cab (B-Type) (3/5)
| 01***16 | Screw | 9 |
| 09***00 | Button | 66 |
| 23***70 | Board | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Operator'S Cab (B-Type) (4/5)
| 01***12 | Bolt, Bolt,(No Need To Quick Shift) | 2 |
| 01***16 | Screw | 2 |
| 01***10 | Screw (Op) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Operator'S Cab (B-Type) (5/5)
| 01***16 | Bolt, Mount Washer Tank To Bracket, Bolt | 4 |
| 01***20 | Bolt,(With Auto Emergency Steering) | 6 |
| 01***25 | Bolt,Without Revolution Sensor | 6 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Operator'S Cab (C-Type) (1/5)
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 12 |
| 01***55 | Bolt, Mount Lh Bracket | 3 |
| 01***12 | Screw,(Wa250-1p) | 3 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Operator'S Cab (C-Type) (2/5)
| 01***16 | Bolt, Mount Washer Tank To Bracket, Bolt | 4 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 4 |
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 8 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Operator'S Cab (C-Type) (3/5)
| 09***00 | Button | 40 |
| 23***40 | Board,L.H | 1 |
| 23***50 | Board,R.H | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Operator'S Cab (C-Type) (4/5)
| 01***12 | Bolt, Bolt,(No Need To Quick Shift) | 2 |
| 01***16 | Screw | 2 |
| 01***10 | Screw (Op) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Operator'S Cab (C-Type) (5/5)
| 01***16 | Bolt, Mount Washer Tank To Bracket, Bolt | 4 |
| 01***20 | Bolt,(With Auto Emergency Steering) | 6 |
| 01***25 | Bolt,Without Revolution Sensor | 6 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Operator'S Compartment (1/2)
| 01***40 | Bolt, Mount Master Brake Cylinder | 4 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 11 |
| 01***30 | Bolt,(Not Used With Emergency Str.) | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Operator'S Compartment (2/2)
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 16 |
| 01***35 | Bolt,(For Quick Shift) (Mitsubishi) | 4 |
| 01***32 | Washer,(With Auto Emergency Steering) | 20 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Operator'S Seat
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 5 |
| 01***30 | Bolt,(Not Used With Emergency Str.) | 4 |
| 01***16 | Screw | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Operator'S Seat Belt
| 01***35 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
| 01***32 | Washer,(With Auto Emergency Steering) | 4 |
| 23***10 | Belt,(For Snow Removing) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Radiator Guard And Engine Hood
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 22 |
| 01***20 | Screw | 9 |
| 01***05 | Nut,(For Air Conditioner Less), Nut | 9 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Radiator Guard And Engine Hood (With Vandalism Protection)
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 23 |
| 01***20 | Screw,(Not Used With Ventilator) | 9 |
| 01***05 | Nut,(For Air Conditioner Less), Nut | 9 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Rear Frame
| 01***75 | Bolt | 4 |
| 01***60 | Bolt, Mount Pole | 4 |
| 01***80 | Bolt - Counterweight Mounting | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Rear Frame (Extreme Cold Terrain Spec.)
| 01***15 | Bolt | 6 |
| 01***75 | Bolt | 4 |
| 01***60 | Bolt, Mount Pole | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Rear Wiper
| 01***16 | Screw | 2 |
| 08***11 | Wiper Motor Ass'Y,Front Wiper | 1 |
| 08***00 | Arm,Wiper | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Rops Canopy
| 01***85 | Bolt | 8 |
| 01***60 | Washer,(Without Rops Guard? Canopy) | 8 |
| 04***60 | Screw,Machine Model (For Ec Reg.) | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Rops Canopy Related Parts
| 01***35 | Bolt, Hydraulic Tank Mounting | 4 |
| 01***45 | Washer,(For Travel Motor) (Not Show) | 4 |
| 09***01 | Bolt,(For Shipping) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Side Panel
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 8 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 10 |
| 01***35 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Side Panel (Extreme Cold Terrain Spec.)
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 8 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 10 |
| 01***35 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Steel Canopy
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 10 |
| 01***30 | Bolt-Hex, Bolt,(With Center Guard) | 8 |
| 01***10 | Nut,(Without Air Conditioner) | 16 |
Komatsu : Gd623a-1(S/N 30001-Up) : Frame And Guard : Transmission Under Guard
| 01***45 | Bolt | 8 |
| 01***60 | Flat Washer - M20 (Hardened) | 8 |
| 23***10 | Guard,Under | 1 |
Hydraulic System
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Blade Accumulator Piping
| 01***35 | Bolt | 4 |
| 01***16 | Bolt (With Air Heater & Conditioner) | 8 |
| 01***25 | Bolt,Without Revolution Sensor | 6 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Blade Accumulator Wiring
| 01***12 | Bolt,(With Cylinder Cover) | 2 |
| 01***25 | Washer,Spring?For Additional Rear Lam | 2 |
| 01***16 | Washer,(For 35a Alternator) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Blade Lift Cylinder(#30001-30141)
| 01***75 | Bolt,(Reinforced Type) | 2 |
| 01***16 | Nut - M20 | 2 |
| 01***60 | Washer,(For Large Size Tire) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Blade Lift Cylinder(#30142-)
| 01***75 | Bolt,(Reinforced Type) | 2 |
| 01***16 | Nut - M20 | 2 |
| 01***60 | Flat Washer - M20 (Hardened) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Blade Side Shift Cylinder(#30001-30141)
| 01***12 | Screw | 1 |
| 07***80 | O-Ring,Hydraulic Oil Filter | 1 |
| 07***75 | O-Ring,Cylinder Head | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Blade Side Shift Cylinder(#30142-)
| 07***80 | O-Ring,Hydraulic Oil Filter | 1 |
| 07***75 | O-Ring,Cylinder Head | 1 |
| 07***04 | Bushing,Bushing | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Drawbar Shift Cylinder
| 01***75 | Bolt,(Reinforced Type) | 4 |
| 01***16 | Nut - M20 | 4 |
| 01***60 | Washer,(For Large Size Tire) | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Flow Divider Valve
| 23***10 | Body | 1 |
| 23***30 | O-Ring | 2 |
| 23***40 | Spring | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Hydraulic Control Valve? L.H. (3-Spool)
| 23***00 | Control Valve Ass'Y,L.H | 1 |
| KB***05 | Bracket | 1 |
| KB***51 | Housing | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Hydraulic Control Valve? R.H. (4-Spool)
| 23***00 | Control Valve Ass'Y | 1 |
| KB***49 | Housing,Inlet | 1 |
| KB***05 | Bracket | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Hydraulic Filter(#30001-30094)
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 8 |
| 01***32 | Washer,(With Auto Emergency Steering) | 8 |
| 07***65 | O-Ring,(F5350-62a0 -14 ) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Hydraulic Filter(#30095-)
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 8 |
| 01***30 | Washer, Spring (Supplied W/Spider Assembly), Washer-Spring | 8 |
| 07***65 | O-Ring,(F5350-62a0 -14 ) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Hydraulic Motor
| 23***10 | Seal Ass'Y | 1 |
| 23***11 | Seal Ass'Y | 1 |
| 23***00 | Motor Ass'Y,Hydraulic | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Hydraulic Piping (Articulate Cylinder Line)(#30001-30141)
| 01***60 | Bolt,(For Japan And Sweden) | 2 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 1 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Hydraulic Piping (Articulate Cylinder Line)(#30142-)
| 01***60 | Bolt,(For Japan And Sweden) | 2 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 1 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Hydraulic Piping (Blade Lift Cylinder Line)(#30001-30066)
| 01***55 | Bolt,(10m) | 4 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 4 |
| 01***50 | Bolt,(With Service Valve R.H.) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Hydraulic Piping (Blade Lift Cylinder Line)(#30067-30141)
| 01***55 | Bolt,(10m) | 4 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 2 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Hydraulic Piping (Blade Lift Cylinder Line)(#30142-)
| 01***55 | Bolt,(10m) | 4 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 4 |
| 01***50 | Bolt,(With Service Valve R.H.) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Hydraulic Piping (Blade Side Shift Cylinder Line)(#30001-30141)
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 4 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 4 |
| 01***35 | Bolt,(For Quick Shift) (Mitsubishi) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Hydraulic Piping (Blade Side Shift Cylinder Line)(#30142-)
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 2 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 4 |
| 01***35 | Bolt,(For Quick Shift) (Mitsubishi) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Hydraulic Piping (Control Valve To Tank)
| 01***30 | Bolt,(For Mechanical Governor) | 6 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
| 01***22 | Bolt | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Hydraulic Piping (Drawbar Shift Cylinder Line)
| 01***55 | Bolt,(10m) | 2 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
| 01***50 | Bolt,(With Service Valve R.H.) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Hydraulic Piping (For Circle Revolution)
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 1 |
| 01***45 | Bolt,(For Power Tilt Mech Angle) | 1 |
| 01***32 | Washer,(With Auto Emergency Steering) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Hydraulic Piping (Leaning Cylinder Line)
| 01***55 | Bolt,(10m) | 2 |
| 01***45 | Bolt,(For Power Tilt Mech Angle) | 1 |
| 01***20 | Bolt,(Without Rops Guard? Canopy) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Hydraulic Piping (Tank To Pump To Control Valve)
| 01***35 | Bolt,(For Position Fixing) | 4 |
| 01***90 | Bolt, Priority Valve Mounting | 3 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Hydraulic Pump (For Work Equipment And Steering)
| 23***00 | Pump Ass'Y,Hydraulic | 1 |
| 23***01 | Pump Ass'Y,Hydraulic | 1 |
| KB***01 | Coupling | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Pilot Check Valve (For Articulate)
| 07***14 | O-Ring,(F4350-61a0a-20 ) | 5 |
| 07***14 | Ring,Back-Up (Kit), Ring,Back-Up; Komatsu S/N 20501-22940 - Was 07001-02014 | 3 |
| 07***23 | O-Ring,(For 2nd Travel Speed) (Op) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Pilot Check Valve (For Blade Lift? L.H.)
| 07***14 | O-Ring,(F4350-61a0a-20 ) | 2 |
| 07***14 | Ring,Back-Up (Kit), Ring,Back-Up; Komatsu S/N 20501-22940 - Was 07001-02014 | 1 |
| 07***23 | O-Ring,(For 2nd Travel Speed) (Op) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Pilot Check Valve (For Blade Lift? R.H.)
| 07***10 | O-Ring,Plate | 1 |
| 07***14 | O-Ring,(F4350-61a0a-20 ) | 3 |
| 07***10 | Ring,Back-Up | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Pilot Check Valve (For Leaning And Drawbar)
| 07***14 | O-Ring,(F4350-61a0a-20 ) | 6 |
| 07***14 | Ring,Back-Up (Kit), Ring,Back-Up; Komatsu S/N 20501-22940 - Was 07001-02014 | 4 |
| 07***23 | O-Ring,(For 2nd Travel Speed) (Op) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Hydraulic System : Swivel Joint
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 2 |
| 01***32 | Washer,(Not Used With Emergency Str.) | 2 |
| 07***65 | O-Ring,(F5350-62a0 -14 ) | 2 |
Mark Plate? Tool And Kit
Komatsu : Gd623a-1(S/N 30001-Up) : Mark Plate? Tool And Kit : Accessory Parts
| 09***50 | Overall,(Special Order) | 1 |
| 09***57 | Cap,(Special Order) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Mark Plate? Tool And Kit : Marks And Plates (English)
| 04***60 | Screw,Machine Model (For Ec Reg.) | 4 |
| 09***00 | Plate? Caution,Recommended Fuel Oil | 1 |
| 09***00 | Plate? Safety,Articulate Lock | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Mark Plate? Tool And Kit : Marks And Plates (Russian)
| 04***60 | Screw,Machine Model (For Ec Reg.) | 4 |
| 09***00 | Plate? Instruction,Fuel | 1 |
| 09***00 | Plate? Safety,Articulate Lock | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Mark Plate? Tool And Kit : Service Kit
| 04***30 | Ring,Snap? Sprocket | 2 |
| 07***65 | O-Ring,Injection Pump Case | 1 |
| 07***75 | O-Ring,Steering Oil Filter | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Mark Plate? Tool And Kit : Spare Parts
| 04***63 | V-Belt Set,(For 50a Alternator) | 1 |
| 23***53 | Pin,(Except Japan) | 4 |
| 23***42 | Pin,Shear | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Mark Plate? Tool And Kit : Tables
Komatsu : Gd623a-1(S/N 30001-Up) : Mark Plate? Tool And Kit : Tool
| 01***80 | Bolt,(With Scarifier) | 1 |
| 09***06 | Wrench Set,8x10? 12x14? 13x17? | 1 |
| 09***41 | Wrench? 36x41,36x41 | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Mark Plate? Tool And Kit : Tool (Extreme Cold Terain Spec.)
| 01***70 | Bolt,Leaning Lock | 1 |
| 07***00 | Pump,Grease | 1 |
| 07***01 | Cartridge,Grease | 1 |
Optional Parts
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Blade And Circle Support (For Power Tilt)
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 4 |
| 01***30 | Bolt,(Not Used With Emergency Str.) | 6 |
| 01***70 | Bolt, Accumulator Mounting Bracket | 6 |
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Front Blade
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 8 |
| 01***40 | Bolt | 8 |
| 01***19 | Nut - M24 | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Front Blade Cylinder
| 07***90 | O-Ring,(Dk029369-0020) (K2) | 1 |
| 07***85 | O-Ring,(For Snow Removing) | 1 |
| 07***85 | Ring,Back-Up? Head | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Front Blade Piping
| 01***30 | Bolt,(For Mechanical Governor) | 2 |
| 01***55 | Bolt,(10m) | 2 |
| 01***50 | Bolt,(With Service Valve R.H.) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Hydraulic Control Lever (For Front Blade)
| 01***05 | Nut,L.H. Thread (D31s) | 1 |
| 01***06 | Nut,(With Back-Up Alarm) (Op), Nut; Was 01580-10806 | 1 |
| 01***08 | Washer,(For Fixed Type Ripper) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Hydraulic Control Lever (For Power Tilt)
| 01***05 | Nut,L.H. Thread (D31s) | 1 |
| 01***06 | Nut,(With Back-Up Alarm) (Op), Nut; Was 01580-10806 | 1 |
| 01***08 | Washer,(For Fixed Type Ripper) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Hydraulic Control Lever (For Scarifier)
| 01***05 | Nut,L.H. Thread (D31s) | 1 |
| 01***06 | Nut,(With Back-Up Alarm) (Op), Nut; Was 01580-10806 | 1 |
| 01***08 | Washer,(For Fixed Type Ripper) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Hydraulic Control Valve? L.H. (4-Spool)
| 23***00 | Control Valve Ass'Y,L.H | 1 |
| KB***99 | Spool Section Ass'Y,Blade Lift? L.H | 1 |
| KB***05 | Bracket | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Hydraulic Control Valve? R.H. (5-Spool)
| 23***00 | Valve Ass'Y,Hydraulic. Control? R.H | 1 |
| KB***49 | Housing,Inlet | 1 |
| KB***05 | Bracket | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Hydraulic Piping (Power Tilt Cylinder Line) (1/3)
| 07***03 | Hose | 1 |
| 23***70 | Tube | 1 |
| 23***91 | Tube | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Hydraulic Piping (Power Tilt Cylinder Line) (2/3)
| 01***55 | Bolt,(10m) | 2 |
| 01***25 | Washer,Spring?For Additional Rear Lam | 2 |
| 07***34 | O-Ring,(For Without Brake Assistor) | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Hydraulic Piping (Power Tilt Cylinder Line) (3/3)
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 3 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
| 01***30 | Washer, Spring (Supplied W/Spider Assembly), Washer-Spring | 5 |
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Hydraulic Piping (Scarifier Cylinder Line)
| 01***55 | Bolt,(10m) | 2 |
| 01***23 | Washer, Wiring Harness Mounting Bracket | 2 |
| 07***34 | O-Ring,(For Without Brake Assistor) | 6 |
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Pilot Check Valve (For Power Tilt)
| 07***10 | O-Ring,Plate | 1 |
| 07***14 | O-Ring,(F4350-61a0a-20 ) | 2 |
| 07***10 | Ring,Back-Up | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Pilot Check Valve (For Ripper)
| 07***10 | O-Ring,Plate | 1 |
| 07***14 | O-Ring,(F4350-61a0a-20 ) | 3 |
| 07***10 | Ring,Back-Up | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Pilot Check Valve (For Scarifier And Front Blade)
| 07***10 | O-Ring,Plate | 1 |
| 07***14 | O-Ring,(F4350-61a0a-20 ) | 3 |
| 07***10 | Ring,Back-Up | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Power Tilt Cylinder
| 04***20 | Ring, Snap | 4 |
| 07***80 | O-Ring,Hydraulic Oil Filter | 1 |
| 07***75 | O-Ring,Cylinder Head | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Push Plate
| 01***10 | Bolt (Op) | 4 |
| 01***19 | Nut - M24 | 4 |
| 01***60 | Washer,(Without Rops Guard? Canopy) | 8 |
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Rear Mount Ripper
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 18 |
| 01***40 | Bolt,(With Service Valve R.H.) | 8 |
| 01***32 | Washer,(Not Used With Emergency Str.) | 34 |
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Ripper Control Lever
| 01***05 | Nut,L.H. Thread (D31s) | 1 |
| 01***06 | Nut,(With Back-Up Alarm) (Op), Nut; Was 01580-10806 | 1 |
| 04***30 | Pin, Snap | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Ripper Cylinder
| 07***00 | O-Ring,(F4350-65a1 -5 ) | 1 |
| 07***95 | O-Ring,(Y1620-11a0a-12) | 1 |
| 07***95 | Ring,Back-Up? Cylinder Head | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Ripper Mounting Parts
| 01***55 | Bolt,(With Hook) | 4 |
| 01***55 | Bolt,(Without Rops Guard? Canopy) | 4 |
| 01***85 | Bolt | 8 |
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Ripper Piping
| 01***25 | Bolt,Without Revolution Sensor | 2 |
| 01***55 | Bolt,(10m) | 2 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Scarifier
| 01***65 | Bolt,(With Canvas Or Rops Canopy) | 16 |
| 01***80 | Bolt,(For Adjustable Rod) | 2 |
| 01***00 | Bolt,(Without Cab) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Scarifier Cylinder
| 07***90 | O-Ring,(Dk029369-0020) (K2) | 1 |
| 07***85 | O-Ring,(For Snow Removing) | 1 |
| 07***85 | Ring,Back-Up? Head | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Scarifier Lifter
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 4 |
| 01***10 | Bolt (Op) | 4 |
| 01***00 | Bolt | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Optional Parts : Swivel Joint (For Power Tilt)
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 2 |
| 01***32 | Washer,(Not Used With Emergency Str.) | 2 |
| 07***65 | O-Ring,(F5350-62a0 -14 ) | 2 |
Power Train
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Articulate Cylinder(#30001-30141)
| 07***90 | O-Ring,(Dk029369-0020) (K2) | 1 |
| 07***85 | O-Ring,(For Snow Removing) | 1 |
| 07***85 | Ring,Back-Up? Head | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Articulate Cylinder(#30142-)
| 07***90 | O-Ring,(Dk029369-0020) (K2) | 1 |
| 07***85 | O-Ring,(For Snow Removing) | 1 |
| 07***05 | Bushing,Cylinder | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Differential Lock Piping (For Differential Lock)
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 2 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
| 01***55 | Bolt, Mount Tube To Switch Pump | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Drive Shaft
| 01***55 | Bolt | 8 |
| 01***32 | Washer,(Not Used With Emergency Str.) | 8 |
| 23***00 | Drive Shaft Ass'Y | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Final Drive Case (1/2)(#30001-30158)
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 8 |
| 01***35 | Bolt, Bolt, Mount Tubes To Switch And Work Pumps | 2 |
| 01***75 | Bolt, Tube Mounting | 8 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Final Drive Case (1/2)(#30159-30217)
| 01***22 | Bolt,(10m) | 16 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 8 |
| 01***35 | Bolt, Bolt, Mount Tubes To Switch And Work Pumps | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Final Drive Case (1/2)(#30218-)
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 8 |
| 01***60 | Bolt,(For Ripper) | 44 |
| 01***25 | Bolt,(Rear Attachment Less) | 16 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Final Drive Case (2/2)
| 01***35 | Bolt, Mount Ground Driven Steering Pump | 20 |
| 01***32 | Washer,(Not Used With Emergency Str.) | 20 |
| 04***28 | Pin, Dowel - Transmission Case, Pin-Dowel | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Final Drive Case (Differential Lock Type) (1/2) (Cage Section O-Ring Type)(#.-..)
| 01***22 | Bolt,(10m) | 16 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 8 |
| 01***80 | Bolt, Mount Tubes To Switch And Work Pumps | 8 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Final Drive Case (Differential Lock Type) (1/2) (Cage Section O-Ring Type)(#30001-.)
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 8 |
| 01***75 | Bolt, Tube Mounting | 8 |
| 01***60 | Bolt,(For Ripper) | 44 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Final Drive Case (Differential Lock Type) (1/2) (Cage Section Seal Type)(#..-)
| 01***18 | Bolt | 16 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 8 |
| 01***80 | Bolt, Mount Tubes To Switch And Work Pumps | 8 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Final Drive Case (Differential Lock Type) (2/2)
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 1 |
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
| 01***30 | Bolt,(Not Used With Emergency Str.) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Final Drive Case (No-Spin Differential Type) (1/2) (Cage Section O-Ring Type)(#.-..)
| 01***22 | Bolt,(10m) | 16 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 8 |
| 01***35 | Bolt, Bolt, Mount Tubes To Switch And Work Pumps | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Final Drive Case (No-Spin Differential Type) (1/2) (Cage Section O-Ring Type)(#30001-.)
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 8 |
| 01***35 | Bolt, Bolt, Mount Tubes To Switch And Work Pumps | 2 |
| 01***75 | Bolt, Tube Mounting | 8 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Final Drive Case (No-Spin Differential Type) (1/2) (Cage Section Seal Type)(#..-)
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 8 |
| 01***75 | Bolt, Tube Mounting | 8 |
| 01***25 | Bolt,(Rear Attachment Less) | 16 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Final Drive Case (No-Spin Differential Type) (2/2)
| 01***35 | Bolt, Bolt, Mount Tubes To Switch And Work Pumps | 4 |
| 01***35 | Bolt, Mount Ground Driven Steering Pump | 16 |
| 01***32 | Washer,(Not Used With Emergency Str.) | 20 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Final Drive Gear (1/2)
| 01***40 | Bolt,For Weight Adjusting Bolt | 3 |
| 01***45 | Bolt, Mounting Cranking Motor | 6 |
| 01***35 | Capscrew - M14 (1)/(2) | 12 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Final Drive Gear (2/2)
| 01***45 | Bolt, Mounting Bracket To Radiator (Top) | 6 |
| 04***30 | Ring,Snap? Sprocket | 2 |
| 06***15 | Bearing | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Final Drive Gear (Differential Lock Type) (1/2)
| 01***35 | Bolt, Bolt, Mount Tubes To Switch And Work Pumps | 8 |
| 01***40 | Bolt,(With Service Valve R.H.) | 3 |
| 01***45 | Bolt, Mounting Bracket To Radiator (Top) | 6 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Final Drive Gear (Differential Lock Type) (2/2)
| 01***45 | Bolt, Mounting Bracket To Radiator (Top) | 6 |
| 04***30 | Ring,Snap? Sprocket | 2 |
| 06***15 | Bearing | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Final Drive Gear (No-Spin Differential Type) (1/2)
| 01***45 | Bolt, Mounting Bracket To Radiator (Top) | 6 |
| 01***40 | Bolt,For Weight Adjusting Bolt | 3 |
| 01***80 | Bolt,For Weight Adjusting Bolt | 8 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Final Drive Gear (No-Spin Differential Type) (2/2)
| 01***45 | Bolt, Mounting Bracket To Radiator (Top) | 6 |
| 04***30 | Ring,Snap? Sprocket | 2 |
| 06***15 | Bearing | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Front Axle (1/3)
| 01***45 | Bolt | 2 |
| 01***35 | Bolt | 1 |
| 01***13 | Nut | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Front Axle (2/3)
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 8 |
| 01***30 | Bolt,(Not Used With Emergency Str.) | 6 |
| 01***50 | Bolt | 16 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Front Axle (3/3)
| 01***30 | Bolt - Pin Mounting | 4 |
| 01***10 | Nut,Lock | 4 |
| 01***31 | Nut | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Hydraulic Pump (For Transmission And Differential Lock) (1/2)
| 23***00 | Pump Ass'Y | 1 |
| KB***51 | Washer,Spring | 4 |
| KB***50 | Washer,Spring | 8 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Hydraulic Pump (For Transmission And Differential Lock) (2/2)
| KB***03 | Pin,Dowel | 2 |
| KB***08 | Gear Ass'Y | 1 |
| KB***01 | Cover | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Joint
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 12 |
| 01***70 | Bolt, Mount Bracket And Oil Inlet Tube, Bolt | 12 |
| 01***35 | Bolt, Bolt, Mount Tubes To Switch And Work Pumps | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Leaning Cylinder
| 07***80 | O-Ring,Hydraulic Oil Filter | 1 |
| 07***75 | O-Ring,Cylinder Head | 1 |
| 07***75 | Ring,Back-Up (Kit) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Parking Brake(#30001-30420)
| 01***60 | Screw | 1 |
| 01***30 | Washer, Spring (Supplied W/Spider Assembly), Washer-Spring | 1 |
| 01***32 | Washer,(Not Used With Emergency Str.) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Parking Brake(#30421-)
| 01***60 | Screw | 1 |
| 01***30 | Washer, Spring (Supplied W/Spider Assembly), Washer-Spring | 1 |
| 01***32 | Washer,(Not Used With Emergency Str.) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Steering Cylinder
| 04***20 | Ring, Snap | 2 |
| 07***45 | O-Ring,(F4350-60a0 -9 ) | 1 |
| 07***48 | O-Ring, (Without Emergency Steering) | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Steering Piping (1/2)
| 01***30 | Bolt,(For Mechanical Governor) | 4 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 1 |
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 6 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Steering Piping (2/2)
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Steering Valve (1/2)
| 23***20 | Ring | 1 |
| 23***60 | Bearing Ass'Y | 1 |
| 23***70 | Race,Bearing | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Steering Valve (2/2)
| 23***40 | Housing Ass'Y | 1 |
| 23***90 | Valve Sub Ass'Y | 1 |
| 23***70 | Spring | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Tandem Drive Case
| 01***30 | Bolt,(Not Used When Towing Winch) | 16 |
| 01***40 | Bolt,For Weight Adjusting Bolt | 12 |
| 01***32 | Washer,(Not Used With Emergency Str.) | 28 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Tandem Drive Case (For Wet Type Disc Brake)
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 2 |
| 01***30 | Bolt,(Not Used With Emergency Str.) | 16 |
| 01***40 | Bolt,(With Service Valve R.H.) | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Tandem Drive Gear And Chain (For Wet Type Disc Brake)
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 8 |
| 01***35 | Bolt, Bolt, Mount Tubes To Switch And Work Pumps | 6 |
| 01***30 | Bolt,(For Rubber Shoe) | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Tandem Drive Gear And Chain )(#30001-30094)
| 01***20 | Bolt,(Without Rops Guard? Canopy) | 4 |
| 01***40 | Bolt,(With Service Valve R.H.) | 6 |
| 01***40 | Bolt,(With Center Guard) | 18 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Tandem Drive Gear And Chain(#30095-)
| 01***20 | Bolt,(Without Rops Guard? Canopy) | 4 |
| 01***40 | Bolt,For Weight Adjusting Bolt | 6 |
| 01***40 | Bolt,(For Slag Handling) (For Usa) | 18 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission (1st Clutch)(#30001-30420)
| 01***00 | Bolt,(For Front Brake Release) | 15 |
| 01***32 | Washer, (Without Emergency Steering) | 15 |
| 04***28 | Pin, Dowel - Transmission Case, Pin-Dowel | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission (1st Clutch)(#30421-)
| 01***00 | Bolt,(For Front Brake Release) | 15 |
| 01***32 | Washer, (Without Emergency Steering) | 15 |
| 04***28 | Pin, Dowel - Transmission Case, Pin-Dowel | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission (2nd Clutch)(#30001-30420)
| 01***70 | Bolt,Rear Carrier (With Gumpad) | 2 |
| 01***45 | Washer,(For Travel Motor) (Not Show) | 2 |
| 04***34 | Pin-Dowel, Pin,Dowel (For Shipping) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission (2nd Clutch)(#30421-)
| 01***70 | Bolt,Rear Carrier (With Gumpad) | 2 |
| 01***45 | Washer,(For Travel Motor) (Not Show) | 2 |
| 04***34 | Pin-Dowel, Pin,Dowel (For Shipping) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission (Control Valve Cover)(#30001-30420)
| 01***50 | Capscrew | 1 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 2 |
| 01***30 | Bolt,(With Body Positioner) | 12 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission (Control Valve Cover)(#30421-)
| 01***50 | Capscrew | 1 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 2 |
| 01***30 | Bolt,(With Body Positioner) | 12 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission (Control Valve) (1/2)(#30001-30420)
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission (Control Valve) (1/2)(#30421-)
| 01***30 | Bolt - M8 X 30lg | 10 |
| 01***45 | Screw | 4 |
| 01***50 | Capscrew | 9 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission (Control Valve) (2/2)(#30001-30420)
| 01***50 | Capscrew | 2 |
| 01***60 | Bolt,(With Body Positioner) | 3 |
| 01***30 | Bolt,(With Body Positioner) | 8 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission (Control Valve) (2/2)(#30421-)
| 01***50 | Capscrew | 2 |
| 01***60 | Bolt,(With Body Positioner) | 3 |
| 01***30 | Bolt,(With Body Positioner) | 8 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission (Forward And 3rd Clutch)(#30001-30420)
| 04***34 | Pin-Dowel, Pin,Dowel (For Shipping) | 2 |
| 04***18 | Ring,Snap (Without R.P.C.U.) | 2 |
| 04***20 | Ring, Retainer | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission (Forward And 3rd Clutch)(#30421-)
| 04***34 | Pin-Dowel, Pin,Dowel (For Shipping) | 2 |
| 04***18 | Ring,Snap (Without R.P.C.U.) | 2 |
| 04***20 | Ring, Retainer | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission (Low And High Clutch)(#30001-30420)
| 01***70 | Capscrew | 2 |
| 01***85 | Bolt | 1 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 7 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission (Low And High Clutch)(#30421-)
| 01***70 | Capscrew | 2 |
| 01***85 | Bolt | 1 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 7 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission (Output Shaft)(#30001-30420)
| 01***30 | Bolt | 4 |
| 01***16 | Bolt - Box Mounting | 4 |
| 01***35 | Bolt, Mount Ground Driven Steering Pump | 25 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission (Output Shaft)(#30421-)
| 01***16 | Bolt - Box Mounting | 4 |
| 01***35 | Bolt, Mount Ground Driven Steering Pump | 25 |
| 01***50 | Bolt | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission (Power Take Off)(#30001-30420)
| 01***16 | Bolt - Seat And Tether Belt Mounting | 2 |
| 01***30 | Bolt,(Not Used When Towing Winch) | 4 |
| 01***35 | Bolt, Mount Ground Driven Steering Pump | 14 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission (Power Take Off)(#30421-)
| 01***16 | Bolt - Seat And Tether Belt Mounting | 2 |
| 01***30 | Bolt,(Not Used When Towing Winch) | 4 |
| 01***35 | Bolt, Mount Ground Driven Steering Pump | 14 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission (Reverse Clutch)(#30001-30420)
| 01***00 | Bolt | 2 |
| 01***45 | Washer,(For Travel Motor) (Not Show) | 2 |
| 04***34 | Pin-Dowel, Pin,Dowel (For Shipping) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission (Reverse Clutch)(#30421-)
| 01***00 | Bolt | 2 |
| 01***45 | Washer,(For Travel Motor) (Not Show) | 2 |
| 04***34 | Pin-Dowel, Pin,Dowel (For Shipping) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission (Transfer Case)(#30001-30420)
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 12 |
| 01***30 | Bolt,(With Body Positioner) | 4 |
| 01***35 | Bolt, Mount Ground Driven Steering Pump | 17 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission (Transfer Case)(#30421-)
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 12 |
| 01***30 | Bolt,(With Body Positioner) | 4 |
| 01***35 | Bolt, Mount Ground Driven Steering Pump | 17 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission (Transmission Case)(#30001-30420)
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 4 |
| 01***35 | Bolt, Mount Ground Driven Steering Pump | 5 |
| 01***40 | Bolt,For Weight Adjusting Bolt | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission (Transmission Case)(#30421-)
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 4 |
| 01***32 | Washer,(With Auto Emergency Steering) | 4 |
| 04***24 | Pin,Dowel (For No.3 Housing) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission Oil Cooler Piping
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 2 |
| 01***50 | Bolt,(With Service Valve R.H.) | 2 |
| 01***60 | Bolt, Mount Tube To Switch Pump | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission Oil Filter(#30001-30088)
| 01***70 | Bolt, Accumulator Mounting Bracket | 4 |
| 01***32 | Washer,(Not Used With Emergency Str.) | 4 |
| 04***12 | Ring, Snap | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission Oil Filter(#30089-)
| 01***60 | Bolt | 4 |
| 01***32 | Washer,(Not Used With Emergency Str.) | 4 |
| 04***12 | Ring, Snap | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission Piping(#30001-30088)
| 01***35 | Bolt,(For Position Fixing) | 4 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 11 |
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission Piping(#30089-)
| 01***35 | Bolt,(For Position Fixing) | 4 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 4 |
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 6 |
Komatsu : Gd623a-1(S/N 30001-Up) : Power Train : Transmission Pump
| 23***00 | Pump Ass'Y | 1 |
| 23***01 | Pump Ass'Y | 1 |
| KB***50 | Washer,Spring | 8 |
Wheel
Komatsu : Gd623a-1(S/N 30001-Up) : Wheel : Wheel And Tubed Tire
| 23***01 | Tire Ass'Y,(Yokohama) | 1 |
| 23***11 | Tire | 1 |
| 23***00 | Tire Ass'Y,14.00-24-12pr | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Wheel : Wheel And Tubeless Tire
| 23***20 | Valve,Stem | 1 |
| 23***40 | O-Ring | 1 |
| 23***20 | Ring,Side | 1 |
Komatsu : Gd623a-1(S/N 30001-Up) : Wheel : Wheel Brake
| 01***35 | Bolt,(For Position Fixing) | 2 |
| 01***10 | Nut,(Without Air Conditioner) | 4 |
| 01***08 | Nut,(For Straight Tilt Dozer) (D65p) | 4 |
Work Equipment
Komatsu : Gd623a-1(S/N 30001-Up) : Work Equipment : Blade
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 2 |
| 01***30 | Bolt,(Not Used With Emergency Str.) | 4 |
| 01***40 | Bolt,(With Center Guard) | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Work Equipment : Blade Lifter
| 01***55 | Bolt, Mount Lh Bracket | 4 |
| 01***35 | Bolt, Hydraulic Tank Mounting | 4 |
| 01***19 | Nut - M24 | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Work Equipment : Blade? Width 4000mm
| 01***40 | Bolt,(With Center Guard) | 4 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 2 |
| 01***30 | Bolt,(Not Used When Towing Winch) | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Work Equipment : Blade? Width 4300mm
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 2 |
| 01***30 | Bolt,(Not Used When Towing Winch) | 4 |
| 01***40 | Bolt,(For Slag Handling) (For Usa) | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Work Equipment : Circle Reverse Gear (1/2)
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 8 |
| 01***55 | Bolt,(Without Rops Guard? Canopy) | 4 |
| 01***35 | Stud | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Work Equipment : Circle Reverse Gear (2/2)
| 01***20 | Bolt, Wiring Harness Mounting Bracket | 1 |
| 01***35 | Bolt, Mount Ground Driven Steering Pump | 2 |
| 01***55 | Bolt | 6 |
Komatsu : Gd623a-1(S/N 30001-Up) : Work Equipment : Circle Support
| 01***35 | Bolt,R.H. Outside And L.H. Inside | 4 |
| 01***24 | Nut,Leaning Lock | 4 |
| 01***45 | Washer,(For Quick Shift) (Mitsubishi) | 4 |
Komatsu : Gd623a-1(S/N 30001-Up) : Work Equipment : Drawbar
| 01***15 | Bolt (Kit) | 1 |
| 01***35 | Bolt,(For Shipping) | 9 |
| 01***50 | Bolt | 2 |
GD623A-1(S/N 30001-UP) serial number reference
The PIN/serial plate on the GD623A-1 is mounted on the main frame near the front of the machine, stamped with the full model designation and serial number rather than a short letter-prefix code. For this model the meaningful identifier is the numeric serial itself: read whether it falls in the 30001-30094 or 30095-and-up production block (export series) or in the separate B1001-UP JPN-domestic series, since parts and some running changes differ between them.
| Prefix | Identifies | Notes |
|---|---|---|
| 30001-30094 | Early production block within S/N 30001-UP | Export-market GD623A-1, powered by the Komatsu 6D125-1 diesel (about 116 kW / 155.6 hp net). Parts catalog lists a different steering wheel for this block than for 30095-and-up units. Treat as a running-change split inside the same S/N 30001-UP manual family, not a separate model. Confirm exact part fitment with your dealer. |
| 30095-UP | Later production block within S/N 30001-UP | Same S/N 30001-UP family and 6D125-1 engine as the 30001-30094 block, but with an updated steering wheel and tandem drive gear and chain per the parts catalog. Komatsu also issued a separate owner/operator manual specifically for this 30095-Up block. Confirm exact part differences with your dealer if diagnosing a driveline or steering component. |
| B1001-UP | Japan-domestic (JPN) market GD623A-1 - separate serial series | Komatsu issued a distinct JPN-market parts and shop manual for the GD623A-1 starting at B1001-UP, run in parallel with the export S/N 30001-UP series rather than as part of it. Listed here only to avoid confusion if you see a B-prefix plate on a GD623A-1 - confirm with your dealer whether it applies to your machine before using S/N 30001-UP literature. |
Frequently asked questions
What engine powers the Komatsu GD623A-1 (S/N 30001-up)?
A Komatsu 6D125-1, a mechanical, pre-electronic six-cylinder diesel of 11.05-11.1 L displacement, rated 116 kW (155.6 hp) at 2200 rpm. It has no ECM or true diagnostic fault codes and is shared across the GD611A-1, GD621A-1, GD622A-1, GD625A-1, and GD661A-1 grader family.
What is the operating weight of the GD623A-1?
Approximately 12,700 kg (27,998.8 lb) in standard configuration.
What replaced the Komatsu GD623A-1?
No specific successor model number is documented for this S/N range in available sources. It was eventually succeeded by Komatsu's later GD-series graders in this class, though an exact replacement model cannot be confirmed.
What GD623A-1(S/N 30001-UP) owners discuss
What do owners say about the engine on the GD623A-1 grader?
The GD623A-1 runs the mechanical, naturally aspirated 6D125-1 inline-six with an inline injection pump and no electronic controls. Operators and techs report that power-loss complaints usually trace back to a small air leak on the low-pressure fuel transfer line, a tired shutoff or check-valve O-ring, or stale/gelled fuel clogging the filter rather than a failed injection pump. A worn governor linkage or weak governor spring is the common cause of idle hunting or surging. Valve lash has no self-adjusting gear and must be reset by hand on a set schedule. Bleed and pressure-check the low side before condemning the pump.
Is it normal for the hydraulic pump to whine or screech at cold start?
Yes, this is widely reported as normal on gear-type hydraulic pumps used on this grader family. Cold, thick oil causes a brief vacuum on the suction side that produces bubbles and a high-pitched whine; it clears within a minute or two as the oil warms and viscosity drops. If the whine persists well after warm-up, or actuator movement stays sluggish, that points to pump wear or an actual suction-side air leak rather than cold oil, and warrants a dealer inspection.
What wear items show up most on the circle, drawbar, and moldboard?
This generation uses a wear-plate style circle rather than the later bearing-type design, so circle play needs periodic adjustment and lubrication; loose or sloppy circle play is a frequent complaint on higher-hour machines and left unchecked it accelerates wear on the drawbar and pinion. Moldboard cutting edges and end bits wear unevenly depending on grading angle and material worked, and operators are advised to rotate or replace them before they run thin enough to expose the structural moldboard to direct wear and impact damage.
Do the tandem/final drive housings leak on these graders?
Seepage or leaks at the tandem walking-beam case and wheel-motor/axle seals is a recurring wear item as hours climb, consistent with what's reported across this mechanical-era grader family. Common root causes are worn face or duo-cone type seals, contamination in the seal cavity, or excess case pressure from a restricted breather or case-drain path. Routine oil sampling from the tandem cases is the practical way operators catch seal wear before it becomes a bigger repair. Because tandem case integrity affects drive-line safety and load-bearing capacity, have your dealer verify seal condition and case oil analysis before returning the machine to heavy service.
What electrical gremlins are commonly reported on machines this age?
As with other mechanical-era Komatsu iron, the recurring complaint is wiring harness conductors that look intact but have fatigued and broken inside the insulation from vibration and repeated articulation, producing intermittent gauge, sender, or light faults that only show up when the machine is moving. Corroded or loose connectors and bad grounds are the other common culprits, and experienced techs chase grounding issues first since it often resolves erratic gauge readings without replacing any component.
What should a buyer check before purchasing a used GD623A-1?
Community consensus points to the same checklist used across this grader family: start the engine cold and warm and listen for unusual injection-pump or governor noise, check for oil leaks and exhaust smoke, and take it for a drive to confirm the transmission and steering respond cleanly. Inspect the circle for play, check moldboard and cutting-edge wear, and look at the tandem walking-beam cases for seepage and confirm oil condition. Test all hydraulic functions (blade lift, tilt, circle turn, articulation) for leaks, worn hoses, or slow cylinders, and run through every gauge, light, and switch to catch harness or sender faults early. Pull maintenance records if available, since undocumented gaps in engine oil and tandem case service are the biggest red flag buyers report. Because steering, circle, and articulation hydraulics are safety-critical on a grader, have your dealer verify these systems on a pre-purchase inspection before relying on the machine in production.
Compiled from owner and technician discussions across the industry — experiences vary by serial range and machine history.
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