Komatsumotor grader(no series)
Komatsu GD521A-1(S/N 10001-UP)
Maintenance schedule, common problems & OEM parts breakdown
The Komatsu GD521A-1 (S/N 10001-up) is a mid-size, mechanical-era motor grader built for road construction and maintenance grading. It runs the Komatsu S6D105-1, a 6-cylinder diesel rated about 101 kW (135.5 hp) at 2500 rpm, driving a powershift transmission with six forward speeds — no electronic engine controls, since this is a pre-ECM design. Standard operating weight runs around 10,800 kg (23,810 lb), varying by configuration, tires, and ballast. Komatsu built the GD521A-1 in the early 1980s as part of its GD500-series grader line, sharing its chassis, engine, and operation and maintenance manual with the lighter GD511A-1 and the closely related GD523A-1. Configurations included standard rear-wheel-drive grading setups plus optional scarifier and ripper attachments for the roughly 3.7 m (12.2 ft) moldboard.
Across the GD500-series family, the core difference between siblings is engine tune and chassis weight rather than a different platform: the GD511A-1 is the lighter, lower-output version, the GD523A-1 is closely related to the GD521A-1, and both share the same engine lineage and parts book. Komatsu later carried the range forward as the GD521A-1E (S/N 12001-up) before moving to its modern GD5-series graders with electronic engine management. In today's used and parts market, the GD521A-1 is valued precisely because it predates that electronics — no ECM, no fault codes, straightforward mechanical fuel and hydraulic systems that independent shops can rebuild without factory diagnostic tools. Parts commonality with the GD511A-1 and GD523A-1 keeps sourcing easier than for a stand-alone model, and well-maintained units still see work on secondary roads, quarries, and yards where simplicity and rebuildability matter more than the latest grade-control electronics.
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 GD521A-1(S/N 10001-UP) specifications
Engine
| Engine model | Komatsu S6D105-1 (S6D105 series), 6-cylinder diesel |
| Gross/net power | 135.5 hp (101 kW) at 2500 rpm (gears 5-6 rating) |
| Displacement | 6.49 L (396 cu in) |
| Cylinders | 6, in-line |
| Emissions tier | Not documented for this pre-Tier engine generation — verify with your dealer |
Weights
| Operating weight | approx. 10,800 kg (23,810 lb) |
| Shipping weight | Not documented for this serial range — verify with your dealer |
| Ground pressure | Not published for this model |
Dimensions
| Overall transport length | approx. 8.17-8.18 m (26.8 ft) |
| Width over tires | approx. 2.41 m (7.9 ft) |
| Height to cab top | approx. 3.51 m (11.5 ft) |
| Wheelbase | approx. 5.79 m (19.0 ft) |
| Tandem axle wheelbase | approx. 1.55 m (5.1 ft) |
| Ground clearance | approx. 0.37 m (1.2 ft), similar front and rear |
| Moldboard (blade) width | 3.72 m (12.2 ft) |
| Moldboard height | 64.5 cm (25.4 in) |
| Blade base length | approx. 2.56 m (8.4 ft) |
| Turning radius | approx. 6.61 m (21.7 ft) |
Performance
| Max forward travel speed | approx. 44.7 km/h (27.8 mph), 6 forward gears |
| Max reverse travel speed | approx. 54.6 km/h (33.9 mph) |
| Articulation angle | 27 degrees |
| Tire size | 13.00-24, 8PR |
| Gradeability | Not documented for this model — verify with your dealer |
Service capacities (summary)
| Fuel tank | approx. 227 L (60 US gal) |
| Hydraulic system | Not documented for this serial range — verify with your dealer |
| Engine oil | Not documented for this serial range — verify with your dealer |
| Cooling system | Not documented for this serial range — verify with your dealer |
Values vary by configuration, region, and serial range — confirm against your machine before planning transport or lifts.
GD521A-1(S/N 10001-UP) fluids & capacities
| System | Capacity | Recommended fluid |
|---|---|---|
| Engine crankcase (with filter) | 9 L (2.4 US gal) | Komatsu genuine engine oil (EO series); SAE grade selected from Komatsu's seasonal viscosity chart by ambient temperature, generally SAE10W in cold climates up through SAE30 or 15W-40 in warm climates. Exact grade breakdown not documented for this serial range in sources reviewed — verify with dealer. |
| Cooling system | 34 L (9.0 US gal) | Permanent-type (ethylene glycol) antifreeze coolant mixed with water per Komatsu supercoolant spec. Exact coolant designation not documented for this serial range in sources reviewed — verify with dealer. |
| Fuel tank | 227 L (60.0 US gal) | Diesel fuel, ASTM D975 No. 2-D or equivalent grade for ambient temperature. |
| Transmission (powershift case) | 34 L (9.0 US gal) | Komatsu powertrain/transmission oil (TO series) or equivalent, graded by ambient temperature. Exact spec code not documented for this serial range in sources reviewed — verify with dealer. |
| Tandem case, total (both sides) | 78 L (20.6 US gal) | Komatsu gear/powertrain oil (TO series) or equivalent, same family as final drive lubrication on graders of this generation. |
| Final drive case | 12 L (3.2 US gal) | Komatsu gear/powertrain oil (TO series) or equivalent, same spec as tandem case. |
| Hydraulic tank | 30 L (7.9 US gal) | Komatsu hydraulic oil (HO series) or equivalent anti-wear hydraulic fluid, graded by ambient temperature. Exact spec code not documented for this serial range in sources reviewed — verify with dealer. |
| Grease (chassis fittings) | Spec only — no fill quantity listed in the OMM | Komatsu multipurpose lithium-based grease, NLGI 2, or equivalent. Exact Komatsu designation not documented for this serial range in sources reviewed — verify with dealer. |
Capacities are refill values from factory literature — always fill to the dipstick/sight gauge, not the number.
Komatsu GD521A-1(S/N 10001-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 GD521A-1(S/N 10001-UP) beyond the schedule
Predictive Maintenance & Fluid Analysis
On the GD521A-1's S6D105-1 diesel, sample oil at every change to track wear-metal trends — this mechanical injection-pump engine has no electronic fault warning. Watch coolant condition closely; wet-liner blocks are prone to cavitation if additive levels aren't maintained. Sample transmission and final-drive oil for metal fines from the powershift clutches and tandem gearing. Track circle and drawbar wear-pad clearance at each grease interval; trend data catches slack before it shows up as blade chatter.
Corrective & Common Repairs
Common GD521A-1 repairs center on the circle-drawbar-moldboard system: worn circle teeth, loose wear shoes, and slack drawbar ball-and-socket joints from decades of grading duty. Powershift transmission clutch packs and the S6D105-1's mechanical injection pump are the usual high-wear items — expect injector and pump reseal work well before any electronic diagnosis is possible, since this pre-ECM engine has none. Tandem final drive seals and wheel-lean cylinders also see frequent leak repairs on higher-hour machines.
Overhaul & Rebuild Points
Major overhaul points on the GD521A-1 fall at the S6D105-1 top end (liners, pistons, injection pump, head) once compression or oil consumption drifts off spec, and at the tandem final drives and powershift transmission clutch packs after several thousand hours of grading service. Circle gear and wear pad sets wear as a unit and are usually rebuilt together rather than piecemeal. Rebuild parts for this engine and driveline are shared with sibling GD511A-1/GD523A-1 graders, easing sourcing.
Seasonal & Environment Servicing
In cold climates, use correct winter-grade engine and hydraulic oil viscosity for the S6D105-1 and circle/lift hydraulics; this mechanical-era machine has no electronic cold-start assist beyond a basic starting aid. In hot, dusty grading environments, shorten air cleaner and radiator core cleaning intervals and check coolant level more often to protect the wet-liner block. Wash mud from circle, drawbar, and tandem walking-beam pivots before greasing to keep abrasive grit out of wear surfaces.
GD521A-1(S/N 10001-UP) common service parts
| Part number | Part | Notes | |
|---|---|---|---|
| 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 → |
| 09637-30262 | Plate? Instruction,Air Cleaner (Double Element) | 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.
GD521A-1(S/N 10001-UP) fault codes & troubleshooting
| Code | Meaning | Likely cause | What to do |
|---|---|---|---|
| Charge lamp (red, battery symbol) | Alternator not charging the battery circuit | Broken or slipping fan/alternator belt, faulty alternator, loose or corroded wiring connection | Stop engine, check belt tension and wiring, test alternator output before resuming work |
| Engine oil pressure lamp (red, oil-can symbol) | Engine lubrication oil pressure has dropped below the safe limit | Low oil level, clogged oil filter, worn oil pump or bearings | Shut engine down immediately, check oil level and filter condition before restart |
| Coolant temperature lamp/gauge in red zone | Engine coolant temperature has exceeded normal operating range | Low coolant level, clogged radiator core, slipping fan belt, faulty thermostat | Idle down, let engine cool, check coolant level and radiator for debris before continuing |
| Air cleaner restriction indicator | Air filter element is clogged, restricting intake airflow | Dust/dirt loading of the air cleaner element over normal service interval | Inspect and clean or replace the air cleaner element per the maintenance schedule |
| Parking brake lamp | Parking brake is engaged | Lever left in applied position, or brake linkage not releasing fully | Confirm lever position; if lamp stays lit with lever released, inspect parking brake linkage |
| Torque converter/steering oil pressure lamp | Hydraulic oil pressure for the transmission/steering circuit is below normal | Low hydraulic oil level, clogged suction strainer, worn pump | Stop and check hydraulic oil level and filter before further operation |
Codes and remedies are general guidance for this model family — always confirm with diagnostic tooling and your dealer before major repairs.
GD521A-1(S/N 10001-UP) attachments & work tools
Moldboard / grading blade
Standard moldboard is about 3.72 m (12.2 ft) wide, roughly 640-660 mm (25-26 in) high, with a base length near 2.56 m (8.4 ft). It carries a bolt-on, through-hardened cutting edge and replaceable end bits and mounts on the drawbar-circle-moldboard assembly, with hydraulic circle rotation and side-shift.
Front scarifier
Mounts to the front draft/lift frame ahead of the front axle and is raised or lowered with the front lift cylinder. Used for light surface scarifying ahead of the blade pass; on graders of this size it is commonly an added option tied to the front lift-group hydraulics rather than standard equipment.
Mid-mounted scarifier
Fits between the front and rear axles under the main frame. Gives better depth control, visibility, and material-breaking ability than a front scarifier, and is offered as an alternative scarifying position for this grader class.
Rear ripper / scarifier
Bolts to a pusher plate behind the moldboard and drawbar, using the rear hydraulic lift circuit. Interchangeable heavy ripper shanks or lighter scarifier teeth can be fitted in the frame slots depending on whether the job calls for breaking hard ground or loosening compacted surface material.
Moldboard wing extension
Bolt-on extension panel that adds extra blade coverage for windrowing, ditching, or wide-pass grading. Sold as a class-wide option rather than a model-specific part for this grader.
Snow equipment
Front-mounted straight snow blade or V-plow, plus a mast-type snow wing that swings out from the side of the machine, are offered as a winter option package for road clearing on graders in this size and weight class.
Circle/drawbar drive and hydraulic guarding
The circle is drawbar-mounted with hydraulic drive for full rotation, blade lift, and side shift, protected by blade accumulators that cushion shock loads to the moldboard, drawbar, and circle. Hydraulics run on a load-sensing system that lets attachment circuits (scarifier, ripper, snow tools) operate together without robbing engine power.
Cab and structural guarding
Factory cab is offered with ROPS/FOPS-rated structure and standard operator guarding; underbody and driveline guards are typical additions when the machine is configured for ripping or scarifying work over rough ground.
All GD521A-1(S/N 10001-UP) assemblies by section
Every catalogued assembly group for the Komatsu GD521A-1(S/N 10001-UP). Open an assembly to preview the parts inside — full OEM part numbers are available in Heavy Parts AI.
Control System
Komatsu : Gd521a-1(S/N 10001-Up) : Control System : Accelerator Padal(#10001-10045)
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 1 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 1 |
| 01***30 | Bolt,(Not Used With Emergency Str.) | 3 |
Komatsu : Gd521a-1(S/N 10001-Up) : Control System : Accelerator Pedal(#10046-)
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 1 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 1 |
Komatsu : Gd521a-1(S/N 10001-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 : Gd521a-1(S/N 10001-Up) : Control System : Booster And Master Cylinder
| 04***30 | Seal, Dust | 1 |
| 23***70 | Seat | 1 |
| 23***20 | Spring | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Control System : Brake Pedal(#10001-10075)
| 01***35 | Bolt,(For Quick Shift) (Mitsubishi) | 1 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 4 |
| 01***08 | Nut,L.H. Thread | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Control System : Brake Pedal(#10076-)
| 01***35 | Bolt,(For Quick Shift) (Mitsubishi) | 1 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 4 |
| 01***08 | Nut,L.H. Thread | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Control System : Brake Piping (1/2)
| 01***12 | Bolt,(With Cylinder Cover) | 2 |
| 01***35 | Bolt, Bolt, Mount Tubes To Switch And Work Pumps | 4 |
| 01***30 | Screw | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Control System : Brake Piping (2/2)
| 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 : Gd521a-1(S/N 10001-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 : Gd521a-1(S/N 10001-Up) : Control System : Fuel Control Lever(#10001-10074)
| 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 : Gd521a-1(S/N 10001-Up) : Control System : Fuel Control Lever(#10075-)
| 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 : Gd521a-1(S/N 10001-Up) : Control System : 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 : Gd521a-1(S/N 10001-Up) : Control System : Hydraulic Control Lever (For Ripper)
| 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 : Gd521a-1(S/N 10001-Up) : Control System : 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 : Gd521a-1(S/N 10001-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 : Gd521a-1(S/N 10001-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 : Gd521a-1(S/N 10001-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 : Gd521a-1(S/N 10001-Up) : Control System : Parking Brake Control Lever
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 2 |
| 01***30 | Bolt,(Not Used With Emergency Str.) | 4 |
| 01***06 | Nut,(With Back-Up Alarm) (Op), Nut; Was 01580-10806 | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Control System : Steering Wheel(#10001-10043)
| 01***11 | Nut - Mounting | 1 |
| 01***26 | Washer,(For Additional Rear Lamp) | 1 |
| 01***32 | Washer,(With Auto Emergency Steering) | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : Control System : Steering Wheel(#10044-)
| 01***11 | Nut - Mounting | 1 |
| 01***07 | Washer, Spring | 1 |
| 01***26 | Washer,(For Additional Rear Lamp) | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Control System : Transmission Control Lever (1/2)
| 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) | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Control System : Transmission Control Lever (2/2)
| 01***50 | Bolt (Kit) | 1 |
| 01***55 | Bolt, Mount Tube To Switch Pump | 2 |
| 01***06 | Nut? L.H. Thread,L.H. Thread (For Chinese) | 2 |
Engine Related Parts And Electrical System
Komatsu : Gd521a-1(S/N 10001-Up) : Engine Related Parts And Electrical System : Air Cleaner Connection(#10001-10043)
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 4 |
| 01***08 | Nut,(For Straight Tilt Dozer) (D65p) | 8 |
| 01***30 | Washer, Spring (Supplied W/Spider Assembly), Washer-Spring | 12 |
Komatsu : Gd521a-1(S/N 10001-Up) : Engine Related Parts And Electrical System : Air Cleaner Connection(#10044-)
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 4 |
| 01***16 | Washer,(With Water Separator) | 4 |
| 07***29 | Clamp, Hose | 1 |
Komatsu : Gd521a-1(S/N 10001-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***14 | Seat,(For Automatic) | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Engine Related Parts And Electrical System : Back-Up Alarm(#10001-.)
| 01***16 | Bolt, Mount Washer Tank To Bracket, Bolt | 2 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 1 |
| 01***16 | Seat,(For Desiccant Type) (Welded) | 1 |
Komatsu : Gd521a-1(S/N 10001-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***12 | Grommet,(Not Used For Cab Spec.) | 1 |
Komatsu : Gd521a-1(S/N 10001-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 : Gd521a-1(S/N 10001-Up) : Engine Related Parts And Electrical System : Battery (Large Capacity)
| 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 : Gd521a-1(S/N 10001-Up) : Engine Related Parts And Electrical System : Caution Lamp
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 3 |
| 01***32 | Washer,(With Auto Emergency Steering) | 3 |
| 08***60 | Bulb? 35w,35w | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Engine Related Parts And Electrical System : Combination Lamp
| 01***12 | Bolt, Bolt,(No Need To Quick Shift) | 1 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 1 |
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : Engine Related Parts And Electrical System : Electrical System (Battery Line)
| 01***30 | Bolt,(For Mechanical Governor) | 2 |
| 01***20 | Bolt,(Without Rops Guard? Canopy) | 2 |
| 01***12 | Washer,(With Body Positioner) | 3 |
Komatsu : Gd521a-1(S/N 10001-Up) : Engine Related Parts And Electrical System : Electrical System (Center)
| 01***12 | Bolt, Bolt,(No Need To Quick Shift) | 3 |
| 01***14 | Bolt,(With Canopy) | 2 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : Engine Related Parts And Electrical System : Electrical System (Rear)
| 01***14 | Bolt | 2 |
| 01***20 | Bolt,(With Auto Emergency Steering) | 1 |
| 01***06 | Nut,(With Back-Up Alarm) (Op), Nut; Was 01580-10806 | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Engine Related Parts And Electrical System : Engine And Transmission Mounting Parts
| 01***35 | Bolt,(For Quick Shift) (Mitsubishi) | 8 |
| 01***40 | Bolt,(With Service Valve R.H.) | 20 |
| 01***60 | Bolt,(For Ripper) | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : Engine Related Parts And Electrical System : Engine Stop Motor And Mounting Parts(#10075-)
| 01***30 | Bolt | 3 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : Engine Related Parts And Electrical System : Front Work Lamp
| 01***30 | Bolt-Hex, Bolt,(With Center Guard) | 2 |
| 01***22 | Seat (Welded) | 2 |
| 01***45 | Washer,(For Quick Shift) (Mitsubishi) | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : Engine Related Parts And Electrical System : Fuel And Hydraulic Tank (With Rops)
Komatsu : Gd521a-1(S/N 10001-Up) : Engine Related Parts And Electrical System : Fuel And Hydraulic Tank (Without Rops)
| 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 : Gd521a-1(S/N 10001-Up) : Engine Related Parts And Electrical System : Fuel Piping
| 01***20 | Bolt,(With Auto Emergency Steering) | 2 |
| 01***23 | Washer, Wiring Harness Mounting Bracket | 2 |
| 07***12 | Gasket,(Without Air Compressor Type) (K1) | 6 |
Komatsu : Gd521a-1(S/N 10001-Up) : Engine Related Parts And Electrical System : Head Lamp
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 1 |
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
| 01***32 | Washer,(With Auto Emergency Steering) | 3 |
Komatsu : Gd521a-1(S/N 10001-Up) : Engine Related Parts And Electrical System : Inspection Lamp
| 01***08 | Screw | 3 |
| 23***40 | Connector | 1 |
| 23***80 | Cap | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Engine Related Parts And Electrical System : Instrument Panel (Center)
| 01***12 | Bolt,(With Cylinder Cover) | 1 |
| 01***16 | Screw | 6 |
| 01***16 | Washer,(For 35a Alternator) | 7 |
Komatsu : Gd521a-1(S/N 10001-Up) : Engine Related Parts And Electrical System : Instrument Panel (Side)
| 01***12 | Bolt, Bolt,(No Need To Quick Shift) | 1 |
| 01***20 | Bolt,(Without Maintenance Monitor) | 6 |
| 01***20 | Bolt,(Without Rops Guard? Canopy) | 3 |
Komatsu : Gd521a-1(S/N 10001-Up) : Engine Related Parts And Electrical System : Radiator Piping(#10001-10048)
| 07***09 | Clamp, Hose - At Water Pump | 4 |
| 23***70 | Elbow | 1 |
| 23***40 | Elbow | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Engine Related Parts And Electrical System : Radiator Piping(#10049-)
| 01***35 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
| 01***75 | Bolt, Mount Main Relief Valve | 2 |
| 01***11 | Nut,(Not Shown) | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : Engine Related Parts And Electrical System : Radiator(#10001-10048)
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 10 |
| 01***80 | Bolt | 2 |
| 01***10 | Nut,L.H. Thread | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : Engine Related Parts And Electrical System : Radiator(#10049-10061)
| 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 : Gd521a-1(S/N 10001-Up) : Engine Related Parts And Electrical System : Radiator(#10062-)
| 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 : Gd521a-1(S/N 10001-Up) : Engine Related Parts And Electrical System : Rear Work Lamp
| 08***12 | Grommet,(Not Used For Cab Spec.) | 1 |
| 08***60 | Bulb? 60/60w | 1 |
| 23***80 | Lamp Ass'Y,Work? Front | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Engine Related Parts And Electrical System : Speed Meter
| 01***30 | Bolt | 4 |
| 01***23 | Washer,(With Auto Emergency Steering) | 4 |
| 08***14 | Clip,(Without Ripper Point Light) | 1 |
Frame And Guard
Komatsu : Gd521a-1(S/N 10001-Up) : Frame And Guard : Canvas Canopy(#.-)
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 10 |
| 01***30 | Bolt-Hex, Bolt,(With Center Guard) | 8 |
| 01***32 | Bolt | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : Frame And Guard : Canvas Canopy(#10001-.)
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 10 |
| 01***30 | Bolt-Hex, Bolt,(With Center Guard) | 8 |
| 01***10 | Nut,(Without Air Conditioner) | 8 |
Komatsu : Gd521a-1(S/N 10001-Up) : Frame And Guard : Front Frame
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 4 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 4 |
| 01***32 | Washer,(With Auto Emergency Steering) | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : Frame And Guard : Front Weight
| 01***10 | Bolt (Op) | 4 |
| 01***19 | Nut - M24 | 4 |
| 01***60 | Washer,(Without Rops Guard? Canopy) | 8 |
Komatsu : Gd521a-1(S/N 10001-Up) : Frame And Guard : Front Weight (For Ripper)
| 01***10 | Bolt (Op) | 6 |
| 01***19 | Nut - M24 | 6 |
| 01***60 | Washer,(Without Rops Guard? Canopy) | 12 |
Komatsu : Gd521a-1(S/N 10001-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 : Gd521a-1(S/N 10001-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 : Gd521a-1(S/N 10001-Up) : Frame And Guard : Operator'S Cab (B-Type) (3/5)
| 01***16 | Screw | 9 |
| 09***00 | Button | 66 |
| 23***70 | Board | 1 |
Komatsu : Gd521a-1(S/N 10001-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 : Gd521a-1(S/N 10001-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 : Gd521a-1(S/N 10001-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 : Gd521a-1(S/N 10001-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 : Gd521a-1(S/N 10001-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 : Gd521a-1(S/N 10001-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 : Gd521a-1(S/N 10001-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 : Gd521a-1(S/N 10001-Up) : Frame And Guard : Operator'S Compartment
| 01***40 | Bolt, Mount Master Brake Cylinder | 4 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 8 |
| 01***30 | Bolt,(Not Used With Emergency Str.) | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : Frame And Guard : Operator'S Seat(#10001-10154)
| 01***14 | Bolt | 4 |
| 01***25 | Screw | 4 |
| 01***06 | Nut,(With Back-Up Alarm) (Op), Nut; Was 01580-10806 | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : Frame And Guard : Operator'S Seat(#10155-)
| 01***06 | Nut,(With Back-Up Alarm) (Op), Nut; Was 01580-10806 | 4 |
| 01***23 | Washer, Wiring Harness Mounting Bracket | 8 |
| 36***01 | Seat Ass'Y | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Frame And Guard : Radiator Guard And Engine Hood
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 17 |
| 01***32 | Washer,(With Auto Emergency Steering) | 17 |
| 23***60 | Washer | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : Frame And Guard : Rear Frame
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 4 |
| 01***35 | Bolt, Bolt, Mount Tubes To Switch And Work Pumps | 1 |
| 01***30 | Bolt,(For Rubber Shoe) | 4 |
Komatsu : Gd521a-1(S/N 10001-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 : Gd521a-1(S/N 10001-Up) : Frame And Guard : Side Cover (With Rops)
| 01***25 | Bolt,Without Revolution Sensor | 2 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 8 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 24 |
Komatsu : Gd521a-1(S/N 10001-Up) : Frame And Guard : Side Cover (Without Rops)
| 01***12 | Bolt,(With Cylinder Cover) | 2 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 8 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 24 |
Hydraulic System
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Blade Lift Cylinder(#10001-10048)
| 01***75 | Bolt,(Reinforced Type) | 2 |
| 01***16 | Nut - M20 | 2 |
| 01***60 | Flat Washer - M20 (Hardened) | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Blade Lift Cylinder(#10049-10200)
| 01***75 | Bolt,(Reinforced Type) | 2 |
| 01***16 | Nut - M20 | 2 |
| 01***60 | Flat Washer - M20 (Hardened) | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Blade Lift Cylinder(#10201-)
| 01***75 | Bolt,(Reinforced Type) | 2 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 1 |
| 01***16 | Nut - M20 | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Blade Shift Cylinder(#10001-10042)
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Blade Shift Cylinder(#10043-10048)
| 07***80 | O-Ring,Hydraulic Oil Filter | 1 |
| 07***75 | O-Ring,Cylinder Head | 1 |
| 07***75 | Ring,Back-Up (Kit) | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Blade Shift Cylinder(#10049-)
| 07***80 | O-Ring,Hydraulic Oil Filter | 1 |
| 07***75 | O-Ring,Cylinder Head | 1 |
| 07***04 | Bushing,Bushing | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Drawbar Shift Cylinder(#10001-10200)
| 01***75 | Bolt,(Reinforced Type) | 4 |
| 01***16 | Nut - M20 | 4 |
| 01***60 | Flat Washer - M20 (Hardened) | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Drawbar Shift Cylinder(#10201-)
| 01***50 | Bolt,(With Service Valve R.H.) | 1 |
| 01***75 | Bolt,(Reinforced Type) | 4 |
| 01***16 | Nut - M20 | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Flow Divider Valve
| 23***10 | Body | 1 |
| 23***30 | O-Ring | 2 |
| 23***40 | Spring | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : 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 : Gd521a-1(S/N 10001-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 : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Control Valve? L.H. (4-Spool) (For Ripper)
| 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 : Gd521a-1(S/N 10001-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 : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Control Valve? R.H. (5-Spool) (For Front Blade)
| 23***00 | Valve Ass'Y,Hydraulic. Control? R.H | 1 |
| KB***49 | Housing,Inlet | 1 |
| KB***05 | Bracket | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Control Valve? R.H. (5-Spool) (For Scarifier)
| 23***00 | Valve Ass'Y,Hydraulic. Control? R.H | 1 |
| KB***49 | Housing,Inlet | 1 |
| KB***05 | Bracket | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Filter(#10001-10043)
| 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 : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Filter(#10044-)
| 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 : Gd521a-1(S/N 10001-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 : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Articulate Cylinder Line)(#10001-10048)
| 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 : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Articulate Cylinder Line)(#10049-10190)
| 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 : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Articulate Cylinder Line)(#10191-)
| 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 : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Blade Lift Cylinder Line)(#10001-10043)
| 01***55 | Bolt,(10m) | 4 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 4 |
| 01***50 | Bolt,(With Service Valve R.H.) | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Blade Lift Cylinder Line)(#10044-10048)
| 01***55 | Bolt,(10m) | 4 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 2 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Blade Lift Cylinder Line)(#10049-10200)
| 01***55 | Bolt,(10m) | 4 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 2 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Blade Lift Cylinder Line)(#10201-)
| 01***55 | Bolt,(10m) | 4 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 4 |
| 01***23 | Washer, Wiring Harness Mounting Bracket | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Blade Shift Cylinder Line)(#10001-10048)
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
| 01***45 | Bolt,(For Power Tilt Mech Angle) | 1 |
| 01***45 | Bolt, Mounting Bracket To Radiator (Top) | 3 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Blade Shift Cylinder Line)(#10049-)
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
| 01***45 | Bolt,(For Power Tilt Mech Angle) | 1 |
| 01***45 | Bolt, Mounting Bracket To Radiator (Top) | 3 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Circle Motor Line)
| 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 : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Control Valve To Tank)
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
| 01***11 | Nut,(With Under Mirror) | 2 |
| 01***32 | Washer,(With Auto Emergency Steering) | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Drawbar Shift Cylinder Line)(#10001-10200)
| 01***55 | Bolt,(10m) | 2 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
| 01***50 | Bolt,(With Service Valve R.H.) | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Drawbar Shift Cylinder Line)(#10201-)
| 01***55 | Bolt,(10m) | 2 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
| 01***23 | Washer, Wiring Harness Mounting Bracket | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Flow Diveder Valve To Control Valve)
| 01***30 | Bolt,(For Mechanical Governor) | 6 |
| 01***23 | Washer, Wiring Harness Mounting Bracket | 6 |
| 07***18 | O-Ring, Divider Valve Mounting | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Front Blade Cylinder Line) (1/2)
| 07***03 | Hose | 1 |
| 23***70 | Tube | 1 |
| 23***91 | Tube | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Front Blade Cylinder Line) (2/2)
| 01***30 | Bolt,(For Mechanical Governor) | 2 |
| 01***55 | Bolt,(10m) | 2 |
| 01***50 | Bolt,(With Service Valve R.H.) | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Leaning Cylinder Line)(#10001-10190)
| 01***55 | Bolt,(10m) | 2 |
| 01***45 | Bolt,(For Power Tilt Mech Angle) | 1 |
| 01***20 | Bolt,(Without Rops Guard? Canopy) | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Leaning Cylinder Line)(#10191-)
| 01***55 | Bolt,(10m) | 2 |
| 01***20 | Bolt,(Without Rops Guard? Canopy) | 2 |
| 01***23 | Washer, Wiring Harness Mounting Bracket | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Power Tilt Cylinder Line) (1/3)
| 07***03 | Hose | 1 |
| 23***70 | Tube | 1 |
| 23***91 | Tube | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Power Tilt Cylinder Line) (2/3)
| 01***55 | Bolt,(10m) | 2 |
| 01***23 | Washer, Wiring Harness Mounting Bracket | 2 |
| 07***34 | O-Ring,(For Without Brake Assistor) | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Power Tilt Cylinder Line) (3/3)(#10001-10200)
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 3 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
| 01***32 | Washer,(With Auto Emergency Steering) | 5 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Power Tilt Cylinder Line) (3/3)(#10201-)
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 1 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
| 01***32 | Washer,(With Auto Emergency Steering) | 3 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Ripper Cylinder Line) (1/2)
| 07***03 | Hose | 1 |
| 23***80 | Tube | 1 |
| 23***91 | Tube | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Ripper Cylinder Line) (2/2)
| 01***55 | Bolt,(10m) | 2 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 4 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Scarifier Cylinder Line) (1/2)
| 07***03 | Hose | 1 |
| 23***70 | Tube | 1 |
| 23***91 | Tube | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Scarifier Cylinder Line) (2/2)(#10001-10190)
| 01***55 | Bolt,(10m) | 2 |
| 01***23 | Washer, Wiring Harness Mounting Bracket | 2 |
| 07***34 | O-Ring,(For Without Brake Assistor) | 6 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Scarifier Cylinder Line) (2/2)(#10191-)
| 01***55 | Bolt,(10m) | 2 |
| 01***23 | Washer, Wiring Harness Mounting Bracket | 2 |
| 07***34 | O-Ring,(For Without Brake Assistor) | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Piping (Tank To Pump To Flow Divider 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 : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Pump (For Work Equipment And Steerng)(#10001-10154)
| 23***00 | Pump Ass'Y,Hydraulic | 1 |
| 23***01 | Pump Ass'Y,Hydraulic | 1 |
| KB***01 | Coupling | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Hydraulic Pump (For Work Equipment And Steerng)(#10155-)
| 23***02 | Pump Ass'Y,Hydraulic | 1 |
| KB***22 | Flange | 1 |
| KB***20 | Plate,Center | 1 |
Komatsu : Gd521a-1(S/N 10001-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 : Gd521a-1(S/N 10001-Up) : Hydraulic System : Pilot Check Valve (For Blade Lift? L.H.)
| 07***10 | O-Ring,Plate | 1 |
| 07***14 | O-Ring,(F4350-61a0a-20 ) | 3 |
| 07***10 | Ring,Back-Up | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Pilot Check Valve (For Blade Lift? R.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 : Gd521a-1(S/N 10001-Up) : Hydraulic System : Pilot Check Valve (For Front Blade)
| 07***10 | O-Ring,Plate | 1 |
| 07***14 | O-Ring,(F4350-61a0a-20 ) | 3 |
| 07***10 | Ring,Back-Up | 1 |
Komatsu : Gd521a-1(S/N 10001-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 : Gd521a-1(S/N 10001-Up) : Hydraulic System : 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 : Gd521a-1(S/N 10001-Up) : Hydraulic System : 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 : Gd521a-1(S/N 10001-Up) : Hydraulic System : Pilot Check Valve (For Scarifier)
| 07***10 | O-Ring,Plate | 1 |
| 07***14 | O-Ring,(F4350-61a0a-20 ) | 3 |
| 07***10 | Ring,Back-Up | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Power Tilt Cylinder(#10001-10200)
| 04***20 | Ring, Snap | 4 |
| 07***80 | O-Ring,Hydraulic Oil Filter | 1 |
| 07***75 | O-Ring,Cylinder Head | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Power Tilt Cylinder(#10201-)
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 1 |
| 01***32 | Washer,(With Auto Emergency Steering) | 1 |
| 04***20 | Ring, Snap | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : 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 : Gd521a-1(S/N 10001-Up) : Hydraulic System : Scarifier Cylinder(#10001-10190)
| 07***80 | O-Ring,Hydraulic Oil Filter | 1 |
| 07***75 | O-Ring,Cylinder Head | 1 |
| 07***75 | Ring,Back-Up (Kit) | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : Scarifier Cylinder(#10191-)
| 07***80 | O-Ring,Hydraulic Oil Filter | 1 |
| 07***75 | O-Ring,Cylinder Head | 1 |
| 07***75 | Ring,Back-Up (Kit) | 1 |
Komatsu : Gd521a-1(S/N 10001-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 |
Komatsu : Gd521a-1(S/N 10001-Up) : Hydraulic System : 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 |
Mark Plate? Tool And Kit
Komatsu : Gd521a-1(S/N 10001-Up) : Mark Plate? Tool And Kit : Marks And Plates
| 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 : Gd521a-1(S/N 10001-Up) : Mark Plate? Tool And Kit : Service Kit (For Hydraulic System And Circle Reverse Gear)
| 07***30 | O-Ring,Housing | 1 |
| 07***20 | O-Ring,R.H. (Kit) | 1 |
| 07***23 | O-Ring,(For 2nd Travel Speed) (Op) | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Mark Plate? Tool And Kit : Service Kit (For Power Train And Steering)
| 07***65 | O-Ring,Injection Pump Case | 1 |
| 07***70 | O-Ring,(For Intake Air Cover) | 1 |
| 07***75 | O-Ring,Steering Oil Filter | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Mark Plate? Tool And Kit : Tables
| 09***80 | Case,(Except Japan) | 1 |
| 23***40 | Plate? Caution,Before Operating | 1 |
| 23***41 | Plate? Caution,Before Operating | 1 |
Komatsu : Gd521a-1(S/N 10001-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 |
Power Train
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Articulate Cylinder(#10001-10048)
| 07***80 | O-Ring,Hydraulic Oil Filter | 1 |
| 07***75 | O-Ring,Cylinder Head | 1 |
| 07***75 | Ring,Back-Up (Kit) | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Articulate Cylinder(#10049-10190)
| 07***80 | O-Ring,Hydraulic Oil Filter | 1 |
| 07***75 | O-Ring,Cylinder Head | 1 |
| 07***45 | Seal,Dust? Cylinder | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Articulate Cylinder(#10191-)
| 07***80 | O-Ring,Hydraulic Oil Filter | 1 |
| 07***75 | O-Ring,Cylinder Head | 1 |
| 07***45 | Seal,Dust? Cylinder | 4 |
Komatsu : Gd521a-1(S/N 10001-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 : Gd521a-1(S/N 10001-Up) : Power Train : Final Drive Case (1/2)
| 01***18 | Bolt | 18 |
| 01***22 | Bolt,(10m) | 16 |
| 01***20 | Bolt,(Without Rops Guard? Canopy) | 8 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Final Drive Case (2/2)
| 01***35 | Bolt, Bolt, Mount Tubes To Switch And Work Pumps | 18 |
| 01***32 | Washer,(Not Used With Emergency Str.) | 18 |
| 04***28 | Pin, Dowel - Transmission Case, Pin-Dowel | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Final Drive Case (No-Spin Differential Type) (1/2)(#.-)
| 01***18 | Bolt | 18 |
| 01***30 | Bolt,(Not Used With Emergency Str.) | 10 |
| 01***85 | Bolt, Mount Tubes To Switch And Work Pumps | 8 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Final Drive Case (No-Spin Differential Type) (1/2)(#10001-.)
| 01***22 | Bolt,(10m) | 16 |
| 01***30 | Bolt,(Not Used With Emergency Str.) | 10 |
| 01***85 | Bolt, Mount Tubes To Switch And Work Pumps | 8 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Final Drive Case (No-Spin Differential Type) (2/2)
| 01***35 | Bolt, Bolt, Mount Tubes To Switch And Work Pumps | 18 |
| 01***32 | Washer,(Not Used With Emergency Str.) | 18 |
| 04***28 | Pin, Dowel - Transmission Case, Pin-Dowel | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Final Drive Gear (1/2)
| 01***35 | Bolt, Bolt, Mount Tubes To Switch And Work Pumps | 3 |
| 01***45 | Bolt, Mounting Bracket To Radiator (Top) | 6 |
| 01***40 | Bolt,R.H. Outside And L.H. Inside, Bolt | 12 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Final Drive Gear (2/2)
| 01***45 | Bolt, Mounting Bracket To Radiator (Top) | 6 |
| 04***54 | Ring,Cotter | 2 |
| 06***14 | Bearing | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Final Drive Gear (No-Spin Differential Type) (1/2)
| 01***35 | Bolt, Bolt, Mount Tubes To Switch And Work Pumps | 3 |
| 01***45 | Bolt, Mounting Bracket To Radiator (Top) | 6 |
| 01***80 | Bolt, Mount Tubes To Switch And Work Pumps | 8 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Final Drive Gear (No-Spin Differential Type) (2/2)
| 01***45 | Bolt, Mounting Bracket To Radiator (Top) | 6 |
| 04***54 | Ring,Cotter | 2 |
| 06***14 | Bearing | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Front Axle (1/3)
| 01***45 | Bolt | 2 |
| 01***35 | Bolt | 1 |
| 01***13 | Nut | 1 |
Komatsu : Gd521a-1(S/N 10001-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 : Gd521a-1(S/N 10001-Up) : Power Train : Front Axle (3/3)
| 01***35 | Bolt,(With Rops) | 3 |
| 01***10 | Nut,Lock | 3 |
| 01***23 | Nut | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Hydraulic Pump (For Transmission)(#10155-)
| 23***03 | Pump Ass'Y,Transmission | 1 |
| KB***22 | Flange | 1 |
| KB***12 | Seal Kit,Transmission Pump | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Joint
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 24 |
| 01***35 | Bolt, Bolt, Mount Tubes To Switch And Work Pumps | 1 |
| 01***32 | Washer,(With Auto Emergency Steering) | 12 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Leaning Cylinder(#10001-10190)
| 07***70 | O-Ring,(For Intake Air Cover) | 1 |
| 07***65 | O-Ring,(F5350-62a0 -14 ) | 1 |
| 07***65 | Ring,Back-Up (Kit) | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Leaning Cylinder(#10191-)
| 07***70 | O-Ring,(For Intake Air Cover) | 1 |
| 07***65 | O-Ring,(F5350-62a0 -14 ) | 1 |
| 07***65 | Ring,Back-Up (Kit) | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Parking Brake(#10001-11000)
| 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 : Gd521a-1(S/N 10001-Up) : Power Train : Parking Brake(#11001-)
| 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 : Gd521a-1(S/N 10001-Up) : Power Train : Steering Cylinder(#10001-10190)
| 04***20 | Ring, Snap | 2 |
| 07***60 | O-Ring,(For Pc750?800?1800) (A2610) | 1 |
| 07***55 | O-Ring,(F4350-62a1 -14 ) | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Steering Cylinder(#10191-)
| 04***20 | Ring, Snap | 2 |
| 07***60 | O-Ring,(For Pc750?800?1800) (A2610) | 1 |
| 07***55 | O-Ring,(F4350-62a1 -14 ) | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Steering Piping (1/2)(#10001-10190)
| 01***40 | Bolt,(With Air Conditioner) | 1 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 1 |
| 01***23 | Washer, Wiring Harness Mounting Bracket | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Steering Piping (1/2)(#10191-)
| 01***40 | Bolt,(With Air Conditioner) | 1 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 1 |
| 01***23 | Washer, Wiring Harness Mounting Bracket | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Steering Piping (2/2)
| 01***30 | Bolt,(For Mechanical Governor) | 4 |
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 6 |
| 01***23 | Washer, Wiring Harness Mounting Bracket | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Steering Valve (1/2)
| 23***20 | Ring | 1 |
| 23***60 | Bearing Ass'Y | 1 |
| 23***70 | Race,Bearing | 2 |
Komatsu : Gd521a-1(S/N 10001-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 : Gd521a-1(S/N 10001-Up) : Power Train : Tandem Drive Case
| 01***30 | Bolt,(Not Used With Emergency Str.) | 16 |
| 01***40 | Bolt,(With Service Valve R.H.) | 12 |
| 01***32 | Washer,(Not Used With Emergency Str.) | 28 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Tandem Drive Gear And Chain
| 01***20 | Bolt,(Without Rops Guard? Canopy) | 4 |
| 01***40 | Bolt,(With Service Valve R.H.) | 6 |
| 01***40 | Bolt,(With Center Guard) | 16 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission (1st And 2nd Clutch)(#10001-11000)
| 01***23 | Washer,(For Shipping) | 18 |
| 04***24 | Pin,Dowel (For No.3 Housing) | 2 |
| 04***28 | Pin, Dowel - Transmission Case, Pin-Dowel | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission (1st And 2nd Clutch)(#11001-)
| 01***23 | Washer,(For Shipping) | 18 |
| 04***24 | Pin,Dowel (For No.3 Housing) | 2 |
| 04***28 | Pin, Dowel - Transmission Case, Pin-Dowel | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission (Control Valve Cover)(#10001-11000)
| 01***50 | Capscrew | 1 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 2 |
| 01***30 | Bolt,(With Body Positioner) | 12 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission (Control Valve Cover)(#11001-)
| 01***50 | Capscrew | 1 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 2 |
| 01***30 | Bolt,(With Body Positioner) | 12 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission (Control Valve) (1/2)(#10001-11000)
| 01***50 | Capscrew | 2 |
| 01***60 | Bolt,(With Body Positioner) | 3 |
| 01***30 | Bolt,(With Body Positioner) | 8 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission (Control Valve) (1/2)(#11001-)
| 01***50 | Capscrew | 2 |
| 01***60 | Bolt,(With Body Positioner) | 3 |
| 01***30 | Bolt,(With Body Positioner) | 8 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission (Control Valve) (2/2)(#10001-11000)
| 01***30 | Bolt - M8 X 30lg | 10 |
| 01***45 | Screw | 4 |
| 01***50 | Capscrew | 9 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission (Control Valve) (2/2)(#11001-)
| 01***30 | Bolt - M8 X 30lg | 10 |
| 01***45 | Screw | 4 |
| 01***50 | Capscrew | 9 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission (Forward And 3rd Clutch)(#10001-11000)
| 04***28 | Pin, Dowel - Transmission Case, Pin-Dowel | 2 |
| 04***18 | Ring,Snap (Without R.P.C.U.) | 1 |
| 04***20 | Ring, Retaining | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission (Forward And 3rd Clutch)(#11001-)
| 04***28 | Pin, Dowel - Transmission Case, Pin-Dowel | 2 |
| 04***18 | Ring,Snap (Without R.P.C.U.) | 1 |
| 04***20 | Ring, Retaining | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission (Input Shaft And Reverse Clutch)(#10001-11000)
| 04***28 | Pin, Dowel - Transmission Case, Pin-Dowel | 4 |
| 04***18 | Ring,Snap (Without R.P.C.U.) | 2 |
| 04***30 | Ring, Snap | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission (Input Shaft And Reverse Clutch)(#11001-)
| 04***28 | Pin, Dowel - Transmission Case, Pin-Dowel | 4 |
| 04***18 | Ring,Snap (Without R.P.C.U.) | 2 |
| 04***30 | Ring, Snap | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission (Low And High Clutch)(#10001-11000)
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 7 |
| 01***35 | Bolt,(F4320-52a0 -5 ) | 4 |
| 01***55 | Bolt - Mount Cage To Transmission Case | 18 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission (Low And High Clutch)(#11001-)
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 7 |
| 01***35 | Bolt,(F4320-52a0 -5 ) | 4 |
| 01***55 | Bolt - Mount Cage To Transmission Case | 18 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission (Output Shaft)(#10001-11000)
| 01***35 | Bolt, Mount Ground Driven Steering Pump | 8 |
| 01***50 | Bolt | 1 |
| 01***32 | Washer,(Not Used With Emergency Str.) | 9 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission (Output Shaft)(#11001-)
| 01***35 | Bolt, Mount Ground Driven Steering Pump | 8 |
| 01***50 | Bolt | 1 |
| 01***32 | Washer,(Not Used With Emergency Str.) | 9 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission (Power Take Off)(#10001-11000)
| 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 : Gd521a-1(S/N 10001-Up) : Power Train : Transmission (Power Take Off)(#11001-)
| 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 : Gd521a-1(S/N 10001-Up) : Power Train : Transmission (Transfer Case)(#10001-11000)
| 01***30 | Bolt | 4 |
| 01***16 | Bolt - Box Mounting | 4 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 12 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission (Transfer Case)(#11001-)
| 01***16 | Bolt - Box Mounting | 4 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 12 |
| 01***30 | Bolt,(With Body Positioner) | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission (Transmission Case)(#10001-11000)
| 01***70 | Capscrew | 4 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 4 |
| 01***35 | Bolt, Mount Ground Driven Steering Pump | 18 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission (Transmission Case)(#11001-)
| 01***70 | Capscrew | 4 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 4 |
| 01***35 | Bolt, Mount Ground Driven Steering Pump | 13 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission Filter(#10001-10043)
| 01***70 | Bolt, Accumulator Mounting Bracket | 4 |
| 01***36 | Wahser-Spring, Washer,Spring (Without Towing Winch) | 4 |
| 04***12 | Ring, Snap | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission Filter(#10044-10154)
| 01***60 | Bolt | 4 |
| 01***32 | Washer,(Not Used With Emergency Str.) | 4 |
| 04***12 | Ring, Snap | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission Oil Filter(#10155-)
| 23***03 | Filter Ass'Y | 1 |
| 23***10 | Head | 1 |
| 23***20 | Cartridge | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission Piping(#10001-10043)
| 01***30 | Bolt,(For Mechanical Governor) | 1 |
| 01***35 | Bolt,(For Position Fixing) | 4 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 11 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission Piping(#10044-10154)
| 01***30 | Bolt,(For Mechanical Governor) | 1 |
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 6 |
| 01***50 | Bolt,(With Service Valve R.H.) | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission Piping(#10155-)
| 01***30 | Bolt,(For Mechanical Governor) | 1 |
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 6 |
| 01***50 | Bolt,(With Service Valve R.H.) | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Power Train : Transmission Pump(#10001-10154)
| 23***00 | Pump Ass'Y | 1 |
| 23***01 | Pump Ass'Y | 1 |
| 23***02 | Pump Ass'Y | 1 |
S6d105-1qq Engine S/N 82173-Up
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Air Cleaner(#82173-92779)
| 04***10 | Ring,See Fig. K4010-65a0 | 1 |
| 08***35 | Indicator,Dust (Japanese-English) | 1 |
| 09***61 | Plate? Instruction,(Japanese-English) (Not Shown) | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Air Cleaner(#92780-)
| 08***01 | Indicator,Dust (Japanese-English) | 1 |
| 08***01 | Indicator,Dust Indicator | 1 |
| 09***61 | Plate? Instruction,(Japanese-English) (Not Shown) | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Air Intake Manifold And Connection
| 01***50 | Bolt,(For Trimming Dozer) | 2 |
| 01***65 | Bolt,(For Alternator Bracket Mount) | 10 |
| 01***70 | Bolt | 3 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Alternator (25a) (With Non Hardening Puleey)
| 60***30 | Alternator A. (25a),(With Non Hardening Pulley) | 1 |
| KD***57 | Bearing,Ball? Front | 1 |
| KD***70 | Bracket,Front | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Alternator And Mounting (25a) (Alternator With Non Hardening Pulley)
| 01***25 | Bolt,(Sandy? Dusty Terrain Spec.) | 1 |
| 01***35 | Bolt,(Cold Weather Spec.) | 1 |
| 01***20 | Bolt, Hose Clamps (Inlet And Return Line Hoses) | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Camshaft And Tappet
| 01***25 | Bolt,(Without Auto Priming System) | 2 |
| 01***20 | Bolt,(Forwarded Individually Parts) | 2 |
| 01***25 | Washer,Spring?(Sandy And Dusty Spec.) | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Corrosion Resistor And Piping
| 01***25 | Bolt,(Sandy? Dusty Terrain Spec.) | 4 |
| 01***20 | Bolt, Hose Clamps (Inlet And Return Line Hoses) | 4 |
| 01***29 | Washer,Spring (Cold Weather Spec.) | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Crankshaft
| 01***25 | Bolt - Rear Guard Mounting | 6 |
| 01***45 | Bolt,Nylock | 1 |
| 01***25 | Bolt,L.H. (For Add. Air Compressor) | 6 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Cylinder Block
| 01***30 | Bolt,(For France Noise Suppression) | 4 |
| 01***25 | Bolt, Mount Engine Oil Drain To Fuel Tank | 4 |
| 01***30 | Washer,Spring(Sandy?Dusty Terrain S.) | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Cylinder Head
| 01***25 | Bolt,(Sandy? Dusty Terrain Spec.) | 2 |
| 01***20 | Bolt, Hose Clamps (Inlet And Return Line Hoses) | 2 |
| 01***30 | Washer,Spring(Sandy?Dusty Terrain S.) | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Cylinder Head Cover
| 07***23 | Clamp - Hose | 1 |
| 07***30 | Clip | 1 |
| 61***90 | O-Ring,Breather | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Exhaust Manifold And Turbocharger
| 01***00 | Bolt (M10-1.50x100) | 10 |
| 01***15 | Bolt | 2 |
| 01***00 | Bolt (M10-1.50x100) | 10 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Flywheel And Flywheel Housing
| 01***40 | Bolt,(Dust And Dirt Protection) | 9 |
| 01***60 | Bolt, Trunnion Cap | 2 |
| 01***35 | Screw | 6 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Front Cover And Gear
| 01***22 | Bolt,(Cold Terrain Spec.) | 4 |
| 01***25 | Bolt,(Without Auto Priming System) | 4 |
| 01***60 | Bolt,(Without Alternator Bracket) | 10 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Fuel Filter And Piping(#82173-92779)
| 01***35 | Bolt, Mounting - Flywheel Housing End | 2 |
| 01***30 | Washer,Spring(Sandy?Dusty Terrain S.) | 2 |
| 01***16 | Washer,Radio Controlled Slag Handling | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Fuel Filter And Piping(#92780-)
| 01***25 | Bolt,(Sandy? Dusty Terrain Spec.) | 2 |
| 01***35 | Bolt, Mounting - Flywheel Housing End | 2 |
| 01***20 | Bolt, Hose Clamps (Inlet And Return Line Hoses) | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Fuel Injection Pump (Coupling)
| DK***00 | Bolt | 1 |
| DK***00 | Washer,Lock | 2 |
| DK***00 | Coupling,Cross | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Fuel Injection Pump (Feed Pump)
| DK***20 | Bolt, Joint | 1 |
| DK***20 | Pump,Priming | 1 |
| DK***20 | Housing | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Fuel Injection Pump (Governor) (1/2)
| DK***00 | Adapter | 1 |
| DK***20 | Capsule,Spring | 1 |
| DK***80 | Nut | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Fuel Injection Pump (Governor) (2/2)
| DK***80 | Shim? 0.5mm | 0 |
| DK***00 | Washer,Spring | 1 |
| DK***40 | Gasket,Air Compressor | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Fuel Injection Pump (Pump)
| 61***30 | Injection Pump Ass'Y | 1 |
| DK***10 | Washer,Spring | 1 |
| DK***30 | Bearing | 0 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Fuel Injection Pump And Piping
| 01***70 | Bolt | 4 |
| 01***20 | Bolt,(Large Capacity Type) (Std) | 2 |
| 01***25 | Bolt,(Sandy? Dusty Terrain Spec.) | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Fuel Nozzle And Spill Pipe
| 01***55 | Bolt,(For Trimming Dozer) | 12 |
| 01***55 | Screw | 12 |
| 01***25 | Washer,Spring?(Sandy And Dusty Spec.) | 12 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Gasket Kit
| 07***18 | O-Ring,(See Fig.1601-29?1602-17) | 1 |
| 07***70 | O-Ring,(For Intake Air Cover) | 1 |
| 07***00 | O-Ring,(F4350-65a1 -5 ) | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Gasket Kit (Cold Terrain Spec.)(#92780-)
| 07***18 | O-Ring,(See Fig.1601-29?1602-17) | 1 |
| 07***70 | O-Ring,(For Intake Air Cover) | 1 |
| 07***00 | O-Ring,(F4350-65a1 -5 ) | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Heater Switch And Heater Signal
| 60***70 | Switch,Air Intake Heater | 1 |
| 60***71 | Signal,Signal | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Lubricating Oil Cooler (Cold Terrain Spec.)(#92780-)
| 01***25 | Bolt - Relay Mounting | 1 |
| 01***35 | Bolt, Cover | 1 |
| 01***20 | Screw | 6 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Lubricating Oil Cooler(#82173-92779)
| 01***25 | Bolt,(Without Auto Priming System) | 5 |
| 01***30 | Bolt,(Cold Terrain Spec.) | 3 |
| 01***35 | Bolt,(Without Auto Priming System) | 16 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Lubricating Oil Cooler(#92780-)
| 01***25 | Bolt,(Without Auto Priming System) | 5 |
| 01***30 | Bolt,(Cold Terrain Spec.) | 3 |
| 01***35 | Bolt,(Without Auto Priming System) | 16 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Lubricating Oil Filter And Mounting(#82173-92779)
| 01***65 | Bolt,(For Alternator Bracket Mount) | 1 |
| 01***25 | Bolt,(Sandy? Dusty Terrain Spec.) | 7 |
| 01***35 | Bolt, Mounting - Flywheel Housing End | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Lubricating Oil Filter And Mounting(#92780-)
| 01***90 | Bolt | 1 |
| 01***35 | Bolt, Mounting - Flywheel Housing End | 1 |
| 01***25 | Bolt (M10x1.50x25) | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Lubricating Oil Piping(#82173-92779)
| 01***16 | Bolt,(For Slag Handling) | 2 |
| 01***95 | Bolt | 1 |
| 01***35 | Bolt, Mounting - Flywheel Housing End | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Lubricating Oil Pump And Suction Pipe
| 01***25 | Bolt,(Without Auto Priming System) | 3 |
| 01***30 | Bolt,(Cold Terrain Spec.) | 1 |
| 01***45 | Bolt,(S6d155-4b) | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Muffler And Mounting(#82173-92779)
| 01***40 | Bolt,(For Position Fixing) | 1 |
| 01***25 | Bolt,(Sandy? Dusty Terrain Spec.) | 4 |
| 01***40 | Bolt,(Dust And Dirt Protection) | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Muffler And Mounting(#92780-)
| 01***16 | Bolt,(For Slag Handling) | 2 |
| 01***20 | Bolt,(Large Capacity Type) (Std) | 6 |
| 01***16 | Bolt, Mount Solenoid Valve | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Oil Pan
| 01***22 | Bolt,(Cold Terrain Spec.) | 28 |
| 01***25 | Bolt,(Without Auto Priming System) | 8 |
| 01***30 | Bolt,(Cold Terrain Spec.) | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Oil Pan (Cold Terrain Spec.)(#92780-)
| 01***20 | Bolt,(Forwarded Individually Parts) | 38 |
| 01***20 | Bolt, Hose Clamps (Inlet And Return Line Hoses) | 2 |
| 01***16 | Washer,(For Shipping) | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Piston And Connecting Rod
| 04***18 | Ring, Retaining | 2 |
| 61***40 | Crank Pin Metal A | 6 |
| 61***01 | Connecting Rod Ass'Y,(B) | 6 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Rocker Arm
| 01***80 | Bolt,(Shim 5 Pieces Over) | 2 |
| 01***06 | Nut, Regular Hexagon (M8-1.25) | 12 |
| 01***36 | Washer,Radio Controlled Slag Handling | 6 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Starting Motor (5.5kw)
| 60***90 | Starting Motor Ass'Y,(5.5kw) | 1 |
| KD***30 | Bracket,Center | 1 |
| KD***50 | Clutch Ass'Y,Over Running | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Starting Motor (7.5kw)(#92780-)
| 60***50 | Starting Motor Ass'Y,(7.5kw) | 1 |
| KD***60 | Shift Lever Assembly | 1 |
| KD***40 | Spring,Spring | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Starting Motor And Mounting (5.5kw? 7.5kw)
| 01***35 | Bolt - Torque Converter Totransmission Mounting | 3 |
| 01***30 | Bolt, Mounting - Front Hand Rails | 3 |
| 01***36 | Washer,Radio Controlled Slag Handling | 3 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Turbocharger
| 61***00 | Turbocharger Ass'Y,(T04b-59) | 1 |
| GA***00 | Clamp | 3 |
| GA***01 | Bolt | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Turbocharger Lubricating Oil Piping
| 01***22 | Bolt,(Cold Terrain Spec.) | 2 |
| 01***35 | Bolt, Mounting - Flywheel Housing End | 2 |
| 01***20 | Bolt,(Forwarded Individually Parts) | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : S6d105-1qq Engine S/N 82173-Up : Water Pump And Cooling Fan
| 01***16 | Bolt,(For Slag Handling) | 2 |
| 01***30 | Bolt,(Cold Terrain Spec.) | 3 |
| 01***55 | Bolt,(For Suction? Reversible Fan) | 2 |
Wheel
Komatsu : Gd521a-1(S/N 10001-Up) : Wheel : Wheel And Tire
| 23***50 | Valve,Valve | 1 |
| 23***60 | Cap,Valve | 1 |
| 23***20 | Tube | 1 |
Komatsu : Gd521a-1(S/N 10001-Up) : Wheel : Wheel Brake
| 01***30 | Bolt,(For Mechanical Governor) | 2 |
| 01***45 | Bolt, Mount Center Hinge Retainer (Upper) | 48 |
| 01***10 | Nut,(Without Air Conditioner) | 4 |
Work Equipment
Komatsu : Gd521a-1(S/N 10001-Up) : Work Equipment : Blade And Circle Support
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 2 |
| 01***30 | Bolt,(Not Used With Emergency Str.) | 4 |
| 01***35 | Bolt,R.H. Outside And L.H. Inside | 4 |
Komatsu : Gd521a-1(S/N 10001-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 : Gd521a-1(S/N 10001-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 : Gd521a-1(S/N 10001-Up) : Work Equipment : Circle Reverse Gear (2/2)
| 01***20 | Bolt,(With Auto Emergency Steering) | 1 |
| 01***35 | Bolt, Bolt, Mount Tubes To Switch And Work Pumps | 2 |
| 01***55 | Bolt | 6 |
Komatsu : Gd521a-1(S/N 10001-Up) : Work Equipment : Drawbar
| 01***35 | Bolt,(Without Scarifier) | 8 |
| 01***70 | Bolt | 8 |
| 01***55 | Stud | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : Work Equipment : Front Blade
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 8 |
| 01***40 | Bolt | 8 |
| 01***19 | Nut - M24 | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : Work Equipment : Rear Mount Ripper
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 6 |
| 01***40 | Bolt,(With Service Valve R.H.) | 8 |
| 01***50 | Bolt,(For Tree Pusher) | 4 |
Komatsu : Gd521a-1(S/N 10001-Up) : Work Equipment : Scarifier
| 01***65 | Bolt,(With Canvas Or Rops Canopy) | 16 |
| 01***80 | Bolt,(For Adjustable Rod) | 2 |
| 01***95 | Bolt | 2 |
Komatsu : Gd521a-1(S/N 10001-Up) : Work Equipment : Scarifier Lifter
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 4 |
| 01***90 | Bolt | 4 |
| 01***00 | Bolt | 2 |
Frequently asked questions
What engine powers the Komatsu GD521A-1 (S/N 10001-up) motor grader?
It uses the Komatsu S6D105-1, a 6-cylinder diesel rated about 101 kW (135.5 hp) at 2500 rpm — a mechanical, pre-ECM engine with no electronic fault codes.
What is the operating weight of the GD521A-1?
Standard operating weight is about 10,800 kg (23,810 lb); actual weight varies by configuration, ballast, tires, and attachments such as a scarifier or front counterweight.
What replaced the Komatsu GD521A-1?
Komatsu continued the line as the GD521A-1E (S/N 12001-up), a later-series update, before moving to its modern GD5-series graders. Parts and service documentation are shared closely with sibling GD511A-1 and GD523A-1 of the same generation.
What GD521A-1(S/N 10001-UP) owners discuss
What do mechanics say about the transmission and clutch on this grader?
This machine runs a mechanical, non-powershift drivetrain with a foot clutch and mechanical shift linkage rather than an electronically controlled transmission. Grinding or hard engagement when shifting on machines of this type is most often linkage wear, not internal gearbox damage: pedal free play drifts out of spec as clevis pins and linkage bushings wear, and once free play disappears the clutch no longer fully releases before you try to shift. Check and reset pedal free play (commonly on the order of 25-50 mm / 1-2 in, but confirm against the shop manual for this range) and inspect linkage pins and bushings before assuming a transmission problem.
Steering feels heavy or inconsistent - where do owners look first?
On Komatsu graders of this design, sluggish or wandering steering is usually traced back to basics before anyone condemns the steering pump: suction screen condition, hydraulic oil level and cleanliness in the steering circuit, and a pressure-regulating or relief valve that's sticking or worn. A pump swap done without checking those items first often doesn't fix it. Because loss of steering response on an articulated grader is a safety issue, have your dealer verify steering circuit pressure and relief valve function before replacing major hydraulic components.
What wear pattern shows up on the circle and moldboard on machines like this?
Circle wear on graders in general tracks back to dirty lubrication more than age. Grease or oil on the circle attracts dirt and grit, which packs into the wear shoes and accelerates wear and binding; dry-film lubricant on clean surfaces holds up better long-term. Turning the blade under load is a common cause of accelerated wear and shoe damage, and it's avoidable with operator habit alone. Watch for side-to-side play before the circle starts to rotate and for uneven wear on pinion teeth, both signs the circle needs reshimming rather than just relubing.
Are articulation and tandem components a known wear point on this class of grader?
Yes. The center pin, articulation bushings, and steering cylinder mounts at the frame joint are classic wear points on any articulated grader, and looseness there shows up as play in steering response and uneven tire wear before it becomes an obvious safety issue. Tandem housings are the other recurring spot: dirt and debris packed into the tandem case from working in dusty or muddy conditions is a common way axle seals get taken out over time, leading to gear oil leaks at the tandem case seams. Both are quick visual and hands-on checks during routine walk-arounds.
Does the engine on this series have any known quirks?
This grader's engine is a mechanically injected six-cylinder diesel with no electronic engine controls, so it doesn't have the sensor-driven fault codes that show up on later machines. Issues that do surface on mechanically injected diesels of this vintage tend to be classic diesel-mechanic items: injection pump timing drift, fuel filtration or water contamination accelerating pump and injector wear, and routine cooling system upkeep (water pump, hoses, radiator condition) given the engine's age. Documented owner complaints specific to this exact serial range are thin online, which is typical for a low-population machine this old rather than a sign of a troublesome engine.
What electrical issues come up on a machine this old?
The electrical system on a mechanical-era grader like this is basic - starting, charging, lighting, and gauges - not an engine-control network, so there isn't a body of sensor-fault discussion to draw on. The complaints that do turn up on machines this age are almost always connector corrosion and weak grounds: an inaccurate gauge or an ammeter/charge light that acts up traces back to a corroded or loose connection at the alternator, gauge cluster, or ground strap far more often than to a failed component. Cleaning and tightening connections resolves most of it before any part gets replaced.
What should I check when buying a used GD521A-1(S/N 10001-UP)?
Walk the circle first: check for play before rotation starts, uneven wear on pinion teeth, and whether shims have been used to take up wear. Check the moldboard cutting edge for remaining thickness and straightness. Inspect the tandem housings for oil weeping or dirt packing at the seals, and check articulation center pin and bushings for play. Cycle the clutch pedal and shift linkage to feel for excess free play or grinding engagement. Look over the engine for oil and coolant leaks and check exhaust for smoke on startup and under load. Inspect hydraulic hoses and cylinders (steering and blade lift) for cracks, weeping, or repairs. Given the age of this machine, also ask directly whether the engine, transmission, or final drives have been rebuilt and get total hours if the meter is original, since a low reading on a machine this old is itself worth questioning.
Compiled from owner and technician discussions across the industry — experiences vary by serial range and machine history.
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