Komatsumotor grader(no series)
Komatsu GD521A-1E(S/N 12001-UP)
Maintenance schedule, common problems & OEM parts breakdown
The Komatsu GD521A-1E (S/N 12001-UP) is a heavy-duty motor grader in the 20-ton class, designed for road construction, maintenance, and earthmoving. It is powered by the Komatsu S6D102E-2 diesel engine, delivering approximately 135.5 hp (101 kW). Operating weight ranges from 10,800 kg to 15,000 kg depending on configuration. Production years span the early 1990s to mid-2000s. It succeeded the GD521 series and was followed by the GD521-2 series. Configurations offered include standard cab, ROPS/FOPS cab, and various blade widths.
Across the GD521A-1 generation, Komatsu refined the powertrain efficiency and undercarriage durability compared to the earlier GD521 models. The GD521A-1E variant specifically addresses emission standards with the S6D102E-2 engine. In the used and parts market, this machine remains significant due to its robust S6D102E-2 engine, which shares components with other Komatsu heavy equipment, ensuring parts availability. The modular design of the hydraulic system and the availability of aftermarket undercarriage parts keep maintenance costs competitive, sustaining its value in the secondary market.
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-1E(S/N 12001-UP) specifications
Engine
| Model | S6D105 |
| Number of Cylinders | 6 |
| Displacement | 396.1 cu in (6,492 cc) |
| Net Power | 135.5 hp (101 kW) @ 2,500 rpm |
| Max Power | 135.5 hp (101 kW) |
Weights
| Standard Operating Weight | 23,810 lb (10,800 kg) |
Dimensions
| Overall Length | 26.78 ft (8.16 m) |
| Width Over Tires | 7.86 ft (2.40 m) |
| Height to Top of Isomount Cab | 11.44 ft (3.49 m) |
| Wheelbase | 18.97 ft (5.78 m) |
| Tandem Axle Wheelbase | 5.04 ft (1.54 m) |
| Rear Ground Clearance | 1.19 ft (0.36 m) |
| Front Axle Ground Clearance | 1.2 ft (0.37 m) |
| Moldboard Width | 12.2 ft (3.72 m) |
| Moldboard Height | 25.4 in (645 mm) |
| Blade Base | 8.34 ft (2.54 m) |
Performance
| Max Speed - Forward | 44.7 km/h (27.8 mph) |
| Max Speed - Reverse | 54.6 km/h (33.9 mph) |
| Number of Gears - Forward | 6 |
| Articulation Angle | 27 degrees |
| Turning Radius | 21.7 ft (6.61 m) |
Service capacities (summary)
| Fuel Capacity | 60 gal (227 L) |
| Tire Size | 13.00-24-8PR |
Values vary by configuration, region, and serial range — confirm against your machine before planning transport or lifts.
Komatsu GD521A-1E(S/N 12001-UP) maintenance schedule
| Service interval | Tasks |
|---|---|
| Every 10 h |
|
| Every 250 h |
|
| Every 500 h |
|
| Every 1,000 h |
|
| Every 2,000 h |
|
| Every 4,000 h |
|
Servicing the GD521A-1E(S/N 12001-UP) beyond the schedule
Predictive Maintenance & Fluid Analysis
Utilize Komatsu KOWA fluid analysis at every 500-hour interval to monitor engine oil wear metals (iron, copper, lead) and hydraulic oil contamination. Check coolant SCA concentration at 500 hours to prevent liner cavitation in the S6D102E-2 engine. Monitor hydraulic oil particle count to detect pump or valve wear early. Track fuel dilution levels in engine oil to identify injector or piston ring issues. Use KOMTRAX telematics to correlate load frequency with fluid degradation rates for optimized change intervals.
Corrective & Common Repairs
Address frequent S6D102E-2 engine issues by inspecting the turbocharger shaft play and charge air cooler hoses for leaks. Replace hydraulic return filter elements every 500 hours to prevent contamination of the main hydraulic pump. Check steering cylinder seals for external leakage, a common wear point. Inspect the final drive planetary gears for oil contamination indicating seal failure. Replace worn cutting edges and end bits to maintain grading efficiency and reduce frame stress.
Overhaul & Rebuild Points
Plan for S6D102E-2 engine overhaul at 10,000-12,000 hours, focusing on piston rings, cylinder liners, and valve seats. Inspect the transmission clutch packs and torque converter at 8,000 hours for slippage or wear. Evaluate the undercarriage rollers and tracks at 6,000 hours; replace when wear exceeds limits to prevent frame damage. Check the hydraulic pump swash plate and pistons for wear at 10,000 hours. Inspect the steering axle pivot pins and bushings for excessive play requiring replacement.
Seasonal & Environment Servicing
In cold weather, use low-viscosity engine oil and ensure the coolant mixture provides adequate freeze protection. Preheat the engine and hydraulic system before operation in temperatures below -10°C. In dusty environments, check the air filter restriction indicator more frequently and clean the radiator fins daily. In high-humidity or coastal areas, inspect electrical connections for corrosion and grease all pivot points more often to wash out salt. Drain the fuel water separator daily to prevent microbial growth in the tank.
GD521A-1E(S/N 12001-UP) common service parts
| Part number | Part | Notes | |
|---|---|---|---|
| 07281-00197 | Clamp,(With Pre-Fuel Filter) | Fuel system service | Check fitment → |
| 6732-71-6111 | Filter, Fuel - Secondary | Fuel system service | Check fitment → |
| 09637-30163 | Plate? Instruction,Air Cleaner (Single Element) | Air intake service | Check fitment → |
| 600-181-6740 | Element Assembly, Innner And Outer Air Cleaner | Air intake service | Check fitment → |
| 07000-02080 | O-Ring,Hydraulic Oil Filter | Hydraulic service | Check fitment → |
Always confirm against your machine's serial number — cross-check any part in Heavy Parts AI before ordering.
GD521A-1E(S/N 12001-UP) fault codes & troubleshooting
| Code | Meaning | Likely cause | What to do |
|---|---|---|---|
| CA115 | Engine crankshaft speed sensor failure | Broken sensor, wiring issue, or connector corrosion | Replace the speed sensor and verify voltage at the pin connector |
| CA122 | Intake air pressure sensor feedback voltage too high | Sensor malfunction or wiring issue | Verify the intake pressure sensor and wiring |
| CA123 | Intake air pressure sensor feedback voltage too low | Sensor short or airflow restriction | Check for a sensor short or an airflow restriction |
| CA441 | Battery voltage too low | Alternator or battery failure; voltage regulator issue | Replace the alternator or battery; check the voltage regulator |
| CA442 | Battery voltage too high | Alternator or battery failure; voltage regulator issue | Replace the alternator or battery; check the voltage regulator |
| CA451 | Common rail pressure sensor feedback value too high | Malfunction in the rail sensor or actual overpressure condition | Diagnose the fuel rail pressure sensor or pump lines |
| CA452 | Common rail pressure sensor feedback value too low | Malfunction in the rail sensor or low pressure condition | Diagnose the fuel rail pressure sensor or pump lines |
| AA10NX | Air cleaner clogging | Dirty or blocked air filter element | Replace the air filter |
| B@BCNS | Engine coolant overheating | Radiator blockage, fan belt failure, or low coolant level | Check radiator fins, fan belt, and coolant level |
| AB00KE | Charging voltage too low | Alternator failure or loose belt | Replace the alternator or tighten the belt |
Codes and remedies are general guidance for this model family — always confirm with diagnostic tooling and your dealer before major repairs.
GD521A-1E(S/N 12001-UP) attachments & work tools
Moldboard
Standard width is 3.72 m (12.2 ft) with a height of 0.65 m (25.4 in). The blade base measures 2.54 m (8.34 ft). This configuration is standard for the GD521A-1 class.
Cutting Edges
Compatible with standard grader blades and cutting edges. Specific part numbers are not documented in the provided sources; verify with your dealer for exact fitment.
End Bits
Compatible with standard grader end bits. Specific part numbers are not documented in the provided sources; verify with your dealer for exact fitment.
Tires
Standard tire size is 13.00-24-8PR. This size supports the operational weight and ground clearance requirements for this model class.
Hydraulic System
The machine utilizes a hydraulic system for work equipment control. Specific fluid specifications are not detailed in the provided sources; consult the operation and maintenance manual for exact fluid types and capacities.
Engine
Powered by a Komatsu S6D105 engine with 6 cylinders. Net power is 135.5 hp (101 kW) measured at 2500 rpm. Displacement is 396.1 cu in (6.49 L).
Transmission
Features a 6-speed forward and 6-speed reverse transmission. Maximum forward speed is 27.8 mph (44.7 km/h) and maximum reverse speed is 33.9 mph (54.6 km/h).
Steering
Articulated steering with a maximum articulation angle of 27 degrees. Turning radius is 21.7 ft (6.61 m).
Dimensions
Overall length is 26.78 ft (8.16 m). Width over tires is 7.86 ft (2.40 m). Wheelbase is 18.97 ft (5.78 m). Tandem axle wheelbase is 5.04 ft (1.54 m).
Weights
Standard operation weight is 23810 lb (10799 kg). This weight includes standard equipment and fluids.
Fuel Capacity
Fuel tank capacity is 60 gal (227 L).
Clearances
Rear ground clearance is 1.19 ft (0.36 m). Front axle ground clearance is 1.2 ft (0.37 m). Height to top of isomount cab is 11.44 ft (3.49 m).
All GD521A-1E(S/N 12001-UP) assemblies by section
Every catalogued assembly group for the Komatsu GD521A-1E(S/N 12001-UP). Open an assembly to preview the parts inside — full OEM part numbers are available in Heavy Parts AI.
Control System
Komatsu : Gd521a-1e(S/N 12001-Up) : Control System : Accelerator Padal
| 01***22 | Bolt | 1 |
| 01***20 | Bolt, Wiring Harness Mounting Bracket | 1 |
| 01***45 | Screw | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Control System : Air Dryer
| 23***71 | Air Dryer Ass'Y,(Dr-31) | 1 |
| 23***81 | Service Kit,Air Dryer | 1 |
| 23***01 | Valve Body Ass'Y | 1 |
Komatsu : Gd521a-1e(S/N 12001-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-1e(S/N 12001-Up) : Control System : Brake Piping (1/4) (Air Compressor To Air Tank To Governor)
| 01***75 | Capscrew | 2 |
| 01***23 | Washer, Wiring Harness Mounting Bracket | 2 |
| 07***08 | Plug,(Without Auto Priming System) | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Control System : Brake Piping (1/4) (Air Compressor To Air Tank To Governor) (With Air Dryer)
| 01***75 | Capscrew | 2 |
| 01***30 | Bolt,(With Body Positioner) | 4 |
| 01***30 | Bolt,(Not Used When Towing Winch) | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Control System : Brake Piping (2/4) (Air Tank)
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 4 |
| 01***30 | Bolt,(Not Used With Emergency Str.) | 4 |
| 01***08 | Nut,(For Canvas Canopy?Head Guard) | 4 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Control System : Brake Piping (3/4) (Air Tank To Brake Valve)
| 01***16 | Bolt (With Air Heater & Conditioner) | 4 |
| 01***20 | Bolt,(For Mono Lever Steering) | 2 |
| 01***35 | Bolt,(F4320-52a0 -5 ) | 3 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Control System : Brake Piping (4/4) (Brake Valve To Wheel Brake)
| 01***20 | Bolt,(Without Rops Guard? Canopy) | 8 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 2 |
| 01***10 | Nut (K10) | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Control System : Brake Valve
| 01***20 | Bolt,(Without Maintenance Monitor) | 4 |
| 01***25 | Bolt,Without Revolution Sensor | 3 |
| 01***10 | Screw,(For Wiper Switch Earth) | 4 |
Komatsu : Gd521a-1e(S/N 12001-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-1e(S/N 12001-Up) : Control System : Fuel Control Lever
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 2 |
| 01***05 | Nut,L.H. Thread (D31s) | 1 |
| 01***06 | Nut,(With Back-Up Alarm) (Op), Nut; Was 01580-10806 | 3 |
Komatsu : Gd521a-1e(S/N 12001-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-1e(S/N 12001-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-1e(S/N 12001-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-1e(S/N 12001-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-1e(S/N 12001-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-1e(S/N 12001-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-1e(S/N 12001-Up) : Control System : Parking Brake Control Lever
| 01***25 | Bolt,Without Revolution Sensor | 7 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 2 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Control System : Steering Wheel
| 01***11 | Nut - Mounting | 1 |
| 01***07 | Washer, Spring | 1 |
| 01***26 | Washer,(For Additional Rear Lamp) | 1 |
Komatsu : Gd521a-1e(S/N 12001-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 | 2 |
| 01***30 | Bolt,(For Mechanical Governor) | 1 |
Komatsu : Gd521a-1e(S/N 12001-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 (For Russian) | 3 |
Engine Related Parts And Electrical System
Komatsu : Gd521a-1e(S/N 12001-Up) : Engine Related Parts And Electrical System : Air Cleaner
| 09***63 | Plate? Instruction,Air Cleaner (Single Element) | 1 |
| 60***90 | Valve,Dust | 1 |
| 60***40 | Element Assembly, Innner And Outer Air Cleaner | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Engine Related Parts And Electrical System : Back-Up Lamp (Dual Type)
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 1 |
| 01***32 | Washer,(With Auto Emergency Steering) | 1 |
| 08***60 | Lens | 1 |
Komatsu : Gd521a-1e(S/N 12001-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-1e(S/N 12001-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***20 | Bolt, Wiring Harness Mounting Bracket | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Engine Related Parts And Electrical System : Electrical System (Center Line)
| 01***10 | Bolt,(With Auto Emergency Steering) | 1 |
| 01***12 | Bolt, Bolt,(No Need To Quick Shift) | 4 |
| 01***16 | Bolt, Mount Washer Tank To Bracket, Bolt | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Engine Related Parts And Electrical System : Electrical System (Engine Line) (Engine Relay And Slow Blow Fuse)
| 01***14 | Screw | 2 |
| 01***14 | Bolt,(With Canopy) | 2 |
| 01***16 | Bolt - Seat And Tether Belt Mounting | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Engine Related Parts And Electrical System : Electrical System (Engine Line) (Wiring Harness)
| 01***14 | Bolt,(With Canopy) | 1 |
| 01***20 | Bolt,(With Auto Emergency Steering) | 2 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Engine Related Parts And Electrical System : Electrical System (Front Line)
| 01***14 | Bolt,(With Canopy) | 1 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 1 |
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Engine Related Parts And Electrical System : Electrical System (Front Line) (With Tire Carier)
| 01***14 | Bolt,(With Canopy) | 1 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 1 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 8 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Engine Related Parts And Electrical System : Electrical System (Rear Line)
| 08***60 | Bulb? 60/60w | 1 |
| 08***20 | Bulb? 25/10w,Tail And Stop Lamp | 1 |
| 08***20 | Bulb? 25w,Turn Signal And Back-Up Lamp | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Engine Related Parts And Electrical System : Engine And Transmission Mounting Parts
| 01***40 | Bolt,For Weight Adjusting Bolt | 26 |
| 01***50 | Bolt,(For D60pl) | 8 |
| 01***60 | Capscrew | 4 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Engine Related Parts And Electrical System : Engine Related Parts
| 01***12 | Bolt, Bolt,(No Need To Quick Shift) | 2 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 1 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 4 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Engine Related Parts And Electrical System : Fuel And Hydraulic Tank
| 01***20 | Bolt,(For Mono Lever Steering) | 4 |
| 01***25 | Bolt, Pinlock | 1 |
| 01***12 | Screw,(For Side Lamp) (Not Shown) | 5 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Engine Related Parts And Electrical System : Fuel Piping
| 01***20 | Bolt, Wiring Harness Mounting Bracket | 1 |
| 01***23 | Washer, Wiring Harness Mounting Bracket | 1 |
| 07***12 | Gasket,(Without Air Compressor Type) (K1) | 4 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Engine Related Parts And Electrical System : Fuel Piping (With Water Separator)
| 01***16 | Bolt - Seat And Tether Belt Mounting | 1 |
| 01***20 | Bolt, Wiring Harness Mounting Bracket | 1 |
| 01***25 | Bolt,(Rear Attachment Less) | 2 |
Komatsu : Gd521a-1e(S/N 12001-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-1e(S/N 12001-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-1e(S/N 12001-Up) : Engine Related Parts And Electrical System : Radiator
| 01***20 | Bolt, Wiring Harness Mounting Bracket | 4 |
| 01***50 | Bolt,For Weight Adjusting Bolt | 2 |
| 01***45 | Bolt,(For 60ton Dump Body) | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Engine Related Parts And Electrical System : Radiator Piping
| 01***25 | Bolt,Without Revolution Sensor | 2 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 1 |
| 01***20 | Bolt,(For Mono Lever Steering) | 5 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Engine Related Parts And Electrical System : Rear Work Lamp (Dual Type)
| 08***60 | Bulb? 60/60w | 1 |
| 23***80 | Lamp Ass'Y,Work? Front | 2 |
| 23***90 | Lens | 1 |
Frame And Guard
Komatsu : Gd521a-1e(S/N 12001-Up) : Frame And Guard : Battery Cover And Lower Side Cover
| 01***20 | Bolt,(For Mono Lever Steering) | 4 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 22 |
| 01***10 | Screw,(With Air Conditioner) | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Frame And Guard : Cab Mount Lamp
| 01***20 | Bolt,(For Mono Lever Steering) | 4 |
| 01***32 | Washer,(With Auto Emergency Steering) | 4 |
| 08***00 | Bulb? 60w | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Frame And Guard : Caution Lamp
| 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 : Gd521a-1e(S/N 12001-Up) : Frame And Guard : Engine Side Panel
Komatsu : Gd521a-1e(S/N 12001-Up) : Frame And Guard : Extinguisher
| 01***14 | Screw | 4 |
| 01***16 | Bolt - Seat And Tether Belt Mounting | 3 |
| 01***10 | Washer,See Fig. K4010-12a0 | 3 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Frame And Guard : Front Frame
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 4 |
| 01***20 | Bolt,(For Mono Lever Steering) | 28 |
| 01***32 | Washer,(With Auto Emergency Steering) | 28 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Frame And Guard : Front Side Mirror
| 01***25 | Bolt,Without Revolution Sensor | 2 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 2 |
| 01***06 | Nut,(With Back-Up Alarm) (Op), Nut; Was 01580-10806 | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Frame And Guard : Front Side Mirror (With Tire Carier)
| 01***25 | Bolt,Without Revolution Sensor | 2 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 2 |
| 01***06 | Nut,(With Back-Up Alarm) (Op), Nut; Was 01580-10806 | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Frame And Guard : Froor Mat
| 23***10 | Mat,Floor | 1 |
| 23***11 | Mat,Floor | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Frame And Guard : Operator'S Cab (1/6)
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 10 |
| 01***20 | Bolt, Wiring Harness Mounting Bracket | 8 |
| 01***12 | Screw | 6 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Frame And Guard : Operator'S Cab (2/6)
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 4 |
| 01***20 | Bolt, Wiring Harness Mounting Bracket | 18 |
| 01***40 | Bolt (Op) | 8 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Frame And Guard : Operator'S Cab (3/6)
| 23***10 | Panel | 1 |
| 23***20 | Panel | 1 |
| 23***30 | Panel | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Frame And Guard : Operator'S Cab (4/6) (Accessory Parts)
| 01***20 | Bolt,(With Auto Emergency Steering) | 2 |
| 01***10 | Screw | 3 |
| 01***20 | Screw | 4 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Frame And Guard : Operator'S Cab (5/6) (Front Wiper)
| 01***16 | Bolt, Mount Washer Tank To Bracket, Bolt | 2 |
| 01***12 | Screw | 4 |
| 01***16 | Screw | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Frame And Guard : Operator'S Cab (6/6) (Rear Wiper)
| 01***12 | Capscrew - M4 | 4 |
| 01***10 | Screw | 2 |
| 08***12 | Grommet,(Not Used For Cab Spec.) | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Frame And Guard : Operator'S Compartment
| 01***30 | Bolt,(With Body Positioner) | 4 |
| 01***20 | Bolt,(Without Rops Guard? Canopy) | 8 |
| 01***30 | Bolt,(Not Used When Towing Winch) | 12 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Frame And Guard : Radiator Guard And Engine Hood
| 01***12 | Bolt - Front Cover Mounting | 8 |
| 01***20 | Bolt,(For Mono Lever Steering) | 6 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 15 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Frame And Guard : Radio
| 01***08 | Screw | 6 |
| 01***12 | Screw | 4 |
| 01***20 | Screw | 2 |
Komatsu : Gd521a-1e(S/N 12001-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-1e(S/N 12001-Up) : Frame And Guard : Rear View Mirror
| 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 : Gd521a-1e(S/N 12001-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 |
Power Train
Komatsu : Gd521a-1e(S/N 12001-Up) : Power Train : Articulate Cylinder(#12001-12193)
| 07***80 | O-Ring,Hydraulic Oil Filter | 1 |
| 07***75 | O-Ring,Cylinder Head | 1 |
| 07***45 | Seal,Dust? Cylinder | 4 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Power Train : Articulate Cylinder(#12194-)
| 07***80 | O-Ring,Hydraulic Oil Filter | 1 |
| 07***75 | O-Ring,Cylinder Head | 1 |
| 07***45 | Seal,Dust? Cylinder | 4 |
Komatsu : Gd521a-1e(S/N 12001-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-1e(S/N 12001-Up) : Power Train : Final Drive Case (1/2)
| 01***30 | Bolt,(Not Used When Towing Winch) | 2 |
| 01***40 | Bolt,For Weight Adjusting Bolt | 32 |
| 01***60 | Capscrew | 68 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Power Train : Final Drive Case (2/2)
| 01***35 | Bolt, Mount Ground Driven Steering Pump | 18 |
| 01***32 | Washer,(Not Used With Emergency Str.) | 18 |
| 04***28 | Pin, Dowel - Transmission Case, Pin-Dowel | 2 |
Komatsu : Gd521a-1e(S/N 12001-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-1e(S/N 12001-Up) : Power Train : Final Drive Gear (2/2)
| 01***45 | Bolt, Mounting Bracket To Radiator (Top) | 6 |
| 04***54 | Ring,Cotter | 2 |
| 23***10 | Lock,Shaft | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Power Train : Front Axle (1/3)
| 01***45 | Bolt | 2 |
| 01***35 | Bolt | 1 |
| 01***13 | Nut | 1 |
Komatsu : Gd521a-1e(S/N 12001-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-1e(S/N 12001-Up) : Power Train : Front Axle (3/3)
| 01***35 | Bolt,(With Rops) | 3 |
| 01***23 | Nut | 1 |
| 01***32 | Washer,(Not Used With Emergency Str.) | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Power Train : Joint
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 12 |
| 01***35 | Bolt, Bolt, Mount Tubes To Switch And Work Pumps | 1 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 8 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Power Train : Leaning Cylinder(#12001-12193)
| 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-1e(S/N 12001-Up) : Power Train : Leaning Cylinder(#12194-)
| 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-1e(S/N 12001-Up) : Power Train : Steering Cylinder(#12001-12193)
| 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-1e(S/N 12001-Up) : Power Train : Steering Cylinder(#12194-)
| 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-1e(S/N 12001-Up) : Power Train : Steering Piping (1/2)(#12001-12193)
| 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-1e(S/N 12001-Up) : Power Train : Steering Piping (1/2)(#12194-)
| 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-1e(S/N 12001-Up) : Power Train : Steering Piping (2/2)
| 01***30 | Bolt,(With Body Positioner) | 2 |
| 01***32 | Washer,(With Auto Emergency Steering) | 10 |
| 07***28 | O-Ring,(F5350-63a0 -10 ) | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Power Train : Steering Valve (1/2)
| 23***20 | Ring | 1 |
| 23***60 | Bearing Ass'Y | 1 |
| 23***70 | Race,Bearing | 2 |
Komatsu : Gd521a-1e(S/N 12001-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-1e(S/N 12001-Up) : Power Train : Tandem Drive Case
| 01***30 | Bolt,(Not Used With Emergency Str.) | 16 |
| 01***35 | Bolt, Bolt, Mount Tubes To Switch And Work Pumps | 4 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Power Train : Tandem Drive Gear And Chain
| 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 : Gd521a-1e(S/N 12001-Up) : Power Train : Transmission (1st And 2nd Clutch)
| 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-1e(S/N 12001-Up) : Power Train : Transmission (Control Valve Cover)
| 01***50 | Capscrew | 1 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 2 |
| 01***30 | Bolt,(With Body Positioner) | 12 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Power Train : Transmission (Control Valve) (1/2)
| 01***50 | Capscrew | 2 |
| 01***60 | Bolt,(With Body Positioner) | 3 |
| 01***30 | Bolt,(With Body Positioner) | 8 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Power Train : Transmission (Control Valve) (2/2)
| 01***30 | Bolt - M8 X 30lg | 10 |
| 01***45 | Screw | 4 |
| 01***50 | Capscrew | 9 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Power Train : Transmission (Forward And 3rd Clutch)
| 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-1e(S/N 12001-Up) : Power Train : Transmission (Input Shaft And Reverse Clutch)
| 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-1e(S/N 12001-Up) : Power Train : Transmission (Low And High Clutch)
| 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-1e(S/N 12001-Up) : Power Train : Transmission (Output Shaft)
| 01***35 | Bolt, Mount Ground Driven Steering Pump | 8 |
| 01***50 | Bolt | 1 |
| 01***32 | Washer,(Not Used With Emergency Str.) | 9 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Power Train : Transmission (Parking Brake)
| 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-1e(S/N 12001-Up) : Power Train : Transmission (Power Take Off)
| 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-1e(S/N 12001-Up) : Power Train : Transmission (Transfer Case)
| 01***16 | Bolt - Box Mounting | 4 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 12 |
| 01***35 | Bolt,(F4320-52a0 -5 ) | 4 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Power Train : Transmission (Transmission Case)
| 01***70 | Capscrew | 4 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 4 |
| 01***35 | Bolt, Mount Ground Driven Steering Pump | 13 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Power Train : Transmission Oil Cooler Piping
| 01***60 | Bolt, Mount Tube To Switch Pump | 1 |
| 01***50 | Bolt,(Spark Arrester Spec.) | 1 |
| 01***08 | Nut,(For Canvas Canopy?Head Guard) | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Power Train : Transmission Oil Filter
| 23***03 | Filter Ass'Y | 1 |
| 23***10 | Head | 1 |
| 23***22 | Cartridge,Transmission Filter | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Power Train : Transmission Piping
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 2 |
| 01***35 | Bolt, Bolt, Mount Tubes To Switch And Work Pumps | 2 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 4 |
Komatsu : Gd521a-1e(S/N 12001-Up) : Power Train : Transmission Pump
| 23***03 | Pump Ass'Y,Transmission | 1 |
| KB***22 | Flange | 1 |
| KB***01 | Bolt | 4 |
S6d102e-1t Engine S/N 26200929-Up
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Air Compressor And Piping(#26217579-26232035)
| 01***30 | Bolt,(Water Separator Spec.) | 1 |
| 01***40 | Screw | 2 |
| 01***50 | Screw | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Air Compressor And Piping(#26232036-)
| 01***30 | Bolt,(Water Separator Spec.) | 1 |
| 01***40 | Screw | 2 |
| 01***45 | Bolt | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Air Connector(#26204449-)
| 07***08 | Plug,(Without Auto Priming System) | 1 |
| 67***10 | Plug, Pipe (1/2-14 Npt) | 2 |
| 67***20 | Plug, Pipe (3/4 Nptf) | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Air Intake Heater
| 67***10 | Gasket | 1 |
| 67***11 | Gasket,Air Intake Heater | 1 |
| 67***10 | Harness, Wiring | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Alternator (25a) (Inner Parts)(#26217579-26238641)
| 60***10 | Alternator A. (25a) | 1 |
| KD***57 | Bearing,Ball? Front | 1 |
| KD***60 | Pulley,Non Hardening | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Alternator (25a)(#26217579-26238641)
| (6***0) | Alternator A. (25a),(See Fig.A601p-02a5) | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Alternator (50a) (Inner Parts)(#26200929-26239267)
| 60***10 | Alternator A. (50a) | 1 |
| KD***70 | Bushing,Insulate | 2 |
| KD***40 | Bushing,Insulate | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Alternator (50a) (Inner Parts)(#26239268-)
| 60***10 | Alternator A. (50a) | 1 |
| KD***70 | Bushing,Insulate | 2 |
| KD***40 | Bushing,Insulate | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Alternator (50a)(#26200929-26239267)
| (6***0) | Alternator A. (50a),(See Fig.A601p-02a4z) | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Alternator (50a)(#26239268-)
| (6***0) | Alternator A. (50a),(See Fig.A601p-02a4z) | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Alternator Mounting (For 35a? 50a Alternator)(#26200936-)
| 01***30 | Bolt,(For Trimming Dozer) | 1 |
| 01***10 | Nut,(Without Air Conditioner) | 1 |
| 01***23 | Washer,(With Car Heater) | 3 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Alternator Mounting(#26217579-)
| 01***30 | Bolt,(For Trimming Dozer) | 1 |
| 01***11 | Nut (Welded) | 1 |
| 01***23 | Washer,(With Car Heater) | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Belt Tensioner(#26217579-26238641)
| 67***20 | Bolt (M10x1.50x70) | 1 |
| 67***30 | Tensioner, Belt | 1 |
| 67***20 | Capscrew, Flat Head (M8-1.25x25) | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Belt Tensioner(#26238642-)
| 67***40 | Tensioner,Belt | 1 |
| 67***41 | Tensioner, Alternator Belt | 1 |
| 67***30 | Tensioner, Alternator Belt | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Boost Tube(#26206782-26237080)
| 07***12 | Gasket,Injection Pump Piping | 2 |
| 67***10 | Screw, Banjo Connector (M12x1.50x24) | 1 |
| 67***60 | Adapter, Female | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Boost Tube(#26237081-)
| 07***12 | Gasket,Injection Pump Piping | 2 |
| 67***10 | Screw, Banjo Connector (M12x1.50x24) | 1 |
| 67***60 | Adapter, Female | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Breather Hose(#26206731-)
| 07***20 | Clamp, Spring Hose | 1 |
| 07***65 | Hose | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Camfollower Cover(#26200929-26232037)
| 67***20 | Bolt, Mounting (M8-1.25x16) | 6 |
| 67***80 | Seal, Grommet | 6 |
| 67***60 | Cover, Push Rod | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Camfollower Cover(#26232038-)
| 67***20 | Bolt, Mounting (M8-1.25x16) | 6 |
| 67***80 | Seal, Grommet | 6 |
| 67***60 | Cover, Push Rod | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Camshaft
| 67***20 | Support, Camshaft Thrust | 1 |
| 67***31 | Gear, Camshaft | 1 |
| 67***60 | Bolt (M8x1.25x22) | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Caution Plate (Japanese-English)(#26200929-26259939)
| 09***08 | Plate? Instruction,Air Cleaner | 1 |
| 67***10 | Plate | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Caution Plate(#26216483-)
| 67***11 | Plate? Name | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Cooling Fan(#26206782-)
| 01***30 | Bolt - Lower Oil Cooler Outlet Tubemounting | 6 |
| 01***35 | Bolt, Mount Bracket To Floor | 4 |
| 60***50 | Fan,(S6d105-1yy? S6d105-1zz) | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Corrosion Resistor(#26201318-)
| 01***80 | Bolt (M10-1.50x80) | 1 |
| 01***16 | Screw | 1 |
| 01***40 | Bolt | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Crank Pulley (Air Conditioner Pulley)
| 01***90 | Bolt,(For Large Fan) | 4 |
| 67***11 | Spacer | 1 |
| 67***10 | Pulley | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Crankshaft
| 67***50 | Gear, Crankshaft | 1 |
| 67***11 | Gear, Crankshaft | 1 |
| 67***10 | Crankshaft Ass'Y | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Cylinder Block Blind Cover And Fuel Feed Pump(#26217494-)
| 07***12 | Gasket,Injection Pump Piping | 2 |
| 67***60 | Bolt, Mounting (M8-1.25x25) | 2 |
| 67***10 | Screw, Banjo Connector (M12x1.50x24) | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Cylinder Block(#26200929-26222207)
| 67***20 | Plug, Pipe (3/4 Nptf) | 1 |
| 67***30 | Plug, Pipe (1/8 Nptf) | 2 |
| 67***90 | Nozzle, Piston Cooling | 6 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Cylinder Block(#26222208-)
| 62***10 | Screw | 1 |
| 62***10 | Seal, O-Ring (M10-1.00) | 3 |
| 67***70 | Cylinder Block Ass'Y | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Cylinder Head
| 67***70 | Head Ass'Y | 1 |
| 67***10 | Retainer, Exhaust Valve Spring | 12 |
| 67***70 | Insert, Exhaust | 6 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Damper
| 67***20 | Bolt (M12x1.25x36) | 4 |
| 67***20 | Damper, Rubber Vibration | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Exhaust Connector Clamp
| 67***20 | Clamp,Turbocharger Outlet Pipe | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Exhaust Manifold Gasket And Bolt(#26201318-)
| 67***30 | Bolt, Mounting (M10x1.50x65) | 12 |
| 67***10 | Gasket, Exhaust Manifold | 6 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Exhaust Manifold(#26206782-)
| 67***20 | Manifold, Exhaust | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Fan Drive Pulley(#26217579-26237080)
| 67***30 | Bearing,Roller | 1 |
| 67***70 | Bolt, Mounting (M8-1.25x40) | 4 |
| 67***20 | Support Ass'Y,Fan | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Fan Drive Pulley(#26237081-)
| 67***30 | Bearing,Roller | 1 |
| 67***70 | Bolt, Mounting (M8-1.25x40) | 4 |
| 67***80 | Support Ass'Y | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Flywheel Housing Plug And Plate(#26265506-)
| 01***25 | Bolt,(With Corrosion Resistor) | 1 |
| 61***90 | Spacer | 1 |
| 63***30 | Plate | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Flywheel Housing Plug(#26200929-26265505)
| 02***13 | Plug | 1 |
| 61***90 | Spacer | 1 |
| 63***30 | Plate | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Flywheel Housing(#26200929-26223713)
| 67***10 | Housing,Flywheel | 1 |
| 67***40 | Gasket, Cover Plate | 1 |
| 67***50 | Plug, O-Ring | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Flywheel Housing(#26223714-26239105)
| 67***40 | Gasket, Cover Plate | 1 |
| 67***50 | Plug, O-Ring | 1 |
| 67***60 | Seal, O-Ring | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Flywheel Housing(#26239106-26265919)
| 67***30 | Plate, Cover | 1 |
| 67***50 | Plug, O-Ring | 1 |
| 67***61 | O-Ring,Bearing Cap | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Flywheel Housing(#26265920-)
| 02***13 | Plug | 1 |
| 67***40 | Cover, Rear | 1 |
| 67***30 | Plate, Cover | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Flywheel(#26217494-)
| 67***20 | Washer, Plain (M12) | 8 |
| 67***80 | Gear, Flywheel Ring | 1 |
| 67***00 | Flywheel Ass'Y | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Front Cover(#26200929-26239105)
| 67***40 | Pin, Timing | 1 |
| 67***50 | Ring, Retaining | 1 |
| 67***60 | Screw, Round Head (M5-0.80x17) | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Front Cover(#26239106-)
| 67***11 | Gasket | 1 |
| 67***40 | Pin, Timing | 1 |
| 67***50 | Ring, Retaining | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Front Gear Train Cover
| 67***80 | Gasket, Accessory Drive Cover | 1 |
| 67***10 | Plate, Accessory Drive Cover | 1 |
| 67***30 | Bolt, Flange Head (M12-1.75x25) | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Front Hanger
| 01***25 | Bolt, Mount Engine Oil Drain To Fuel Tank | 4 |
| 67***40 | Bracket | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Fuel Filter
| 67***40 | Bolt, (M8x1.25x35) | 2 |
| 67***10 | Cartridge,Fuel | 1 |
| 67***11 | Filter, Fuel - Secondary | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Fuel Filter Piping(#26217494-26218239)
| 07***12 | Gasket,Injection Pump Piping | 2 |
| 67***60 | Tube, Fuel Supply | 1 |
| 67***70 | Clamp, Tube | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Fuel Filter Piping(#26218240-)
| 07***12 | Gasket,Injection Pump Piping | 2 |
| 67***60 | Tube, Fuel Supply | 1 |
| 67***10 | Bolt, Banjo Connector (M12-1.50x24) | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Fuel Hose Joint(#26217494-26218239)
| 07***12 | Gasket,(Without Air Compressor Type) (K1) | 2 |
| 07***14 | Screw, Banjo Connector (M10) | 1 |
| 61***10 | Connector, Banjo | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Fuel Hose Joint(#26218240-)
| 07***12 | Gasket,(Without Air Compressor Type) (K1) | 2 |
| 07***14 | Screw, Banjo Connector (M10) | 1 |
| 61***10 | Connector, Banjo | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Fuel Injection Pump (Governor) (1/2) (Inner Parts)(#26217494-26237080)
| DK***00 | Washer | 1 |
| DK***00 | Shim? 2.00mm,(High Altitude Spec.) | 0 |
| DK***00 | Shim | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Fuel Injection Pump (Governor) (1/2) (Inner Parts)(#26237081-26245690)
| DK***00 | Shim? 2.00mm,(High Altitude Spec.) | 0 |
| DK***00 | Gasket | 1 |
| DK***40 | Gasket | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Fuel Injection Pump (Governor) (1/2) (Inner Parts)(#26245691-)
| DK***00 | Shim? 2.00mm,(High Altitude Spec.) | 0 |
| DK***00 | Gasket | 1 |
| DK***40 | Gasket | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Fuel Injection Pump (Governor) (2/2) (Inner Parts)(#26217494-26237080)
| DK***00 | Screw | 1 |
| DK***00 | Gasket | 1 |
| DK***40 | Gasket,Air Compressor | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Fuel Injection Pump (Governor) (2/2) (Inner Parts)(#26237081-26245690)
| DK***00 | Screw | 1 |
| DK***00 | Gasket | 1 |
| DK***40 | Gasket,Air Compressor | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Fuel Injection Pump (Governor) (2/2) (Inner Parts)(#26245691-)
| DK***00 | Screw | 1 |
| DK***00 | Gasket | 1 |
| DK***40 | Gasket,Air Compressor | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Fuel Injection Pump (Pump) (1/2) (Inner Parts)(#26217494-26237080)
| 67***60 | Injection Pump Ass'Y | 1 |
| DK***30 | Bearing | 0 |
| DK***20 | Shim, 1.40mm; Was Dk029311-7220, Shim? 1.4mm | 0 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Fuel Injection Pump (Pump) (1/2) (Inner Parts)(#26237081-26245690)
| 67***60 | Injection Pump Ass'Y | 1 |
| DK***30 | Bearing | 0 |
| DK***20 | Shim, 1.40mm; Was Dk029311-7220, Shim? 1.4mm | 0 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Fuel Injection Pump (Pump) (1/2) (Inner Parts)(#26245691-)
| 67***60 | Injection Pump Ass'Y | 1 |
| DK***30 | Bearing | 0 |
| DK***20 | Shim, 1.40mm; Was Dk029311-7220, Shim? 1.4mm | 0 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Fuel Injection Pump (Pump) (2/2) (Inner Parts)(#26217494-26237080)
| DK***40 | Shim? 0.50mm, Shim, 0.50mm; Was Dk029311-0040 | 0 |
| DK***90 | Shim? 0.25mm, Shim, 0.25mm; Was Dk029311-0590 | 0 |
| DK***00 | Sleeve,Control | 6 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Fuel Injection Pump (Pump) (2/2) (Inner Parts)(#26237081-26245690)
| DK***40 | Shim? 0.50mm, Shim, 0.50mm; Was Dk029311-0040 | 0 |
| DK***90 | Shim? 0.25mm, Shim, 0.25mm; Was Dk029311-0590 | 0 |
| DK***00 | Sleeve,Control | 6 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Fuel Injection Pump (Pump) (2/2) (Inner Parts)(#26245691-)
| DK***40 | Shim? 0.50mm, Shim, 0.50mm; Was Dk029311-0040 | 0 |
| DK***90 | Shim? 0.25mm, Shim, 0.25mm; Was Dk029311-0590 | 0 |
| DK***00 | Sleeve,Control | 6 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Fuel Injection Pump And Oil Piping(#26217494-26237080)
| 07***12 | Gasket,(Without Air Compressor Type) (K2) | 2 |
| 07***10 | Screw, Banjo Connector (M10-1.25x20) | 1 |
| 61***40 | Nipple | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Fuel Injection Pump And Oil Piping(#26237081-26245690)
| 07***12 | Gasket,(Without Air Compressor Type) (K2) | 2 |
| 62***10 | Seal, O-Ring (M10-1.00) | 1 |
| 67***50 | Connector, Female | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Fuel Injection Pump And Oil Piping(#26245691-)
| 07***12 | Gasket,(Without Air Compressor Type) (K2) | 2 |
| 62***10 | Seal, O-Ring (M10-1.00) | 1 |
| 67***50 | Connector, Female | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Fuel Injection Pump Mounting And Gear
| 01***14 | Bolt - Fuel Sensor Mounting | 2 |
| 01***11 | Nut (M14-1.50 Thd), Nut; Was 01582-01411 | 1 |
| 61***61 | Washer, Plain (14mm) | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Fuel Return(#26200929-26231950)
| 01***16 | Bolt, Mount Solenoid Valve | 1 |
| 01***45 | Bolt,(Noise Abatement Part) | 2 |
| 04***08 | Clip | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Fuel Return(#26231951-)
| 01***45 | Bolt,(Noise Abatement Part) | 2 |
| 04***08 | Clip | 1 |
| 61***80 | Spacer | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Head Cover(#26206782-)
| 67***30 | Bolt (M8x1.25x25) | 6 |
| 67***50 | Washer, Plain (3/8 Inch) | 6 |
| 67***81 | Gasket, Valve Cover | 6 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Injection Nozzle
| 67***40 | Nozzle | 1 |
| 67***00 | Nozzle Holder Ass'Y | 6 |
| 67***50 | Seal, Rectangular Ring | 6 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Injection Piping(#26204449-26231950)
| 67***80 | Seal, Grommet | 1 |
| 67***60 | Brace, Tube | 1 |
| 67***30 | Seal, Banjo Connector (6.2 mm) | 6 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Injection Piping(#26231951-)
| 67***80 | Seal, Grommet | 1 |
| 67***60 | Brace, Tube | 1 |
| 67***40 | Screw, Banjo Connector (M6x1.00x14.3) | 6 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Muffler And Mounting(#26217494-)
| 01***20 | Bolt,(Forwarded Individually Parts) | 2 |
| 01***25 | Bolt, Mount Engine Oil Drain To Fuel Tank | 10 |
| 01***30 | Bolt - Lower Oil Cooler Outlet Tubemounting | 4 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Oil Cooler And Oil Filter
| 67***50 | Valve, Pressure Relief | 1 |
| 67***51 | Valve, Pressure Relief | 1 |
| 67***30 | Plug, Pipe (1/8 Nptf) | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Oil Filler(#26217494-26221254)
| 01***70 | Bolt | 1 |
| 01***20 | Bolt, Hose Clamps (Inlet And Return Line Hoses) | 1 |
| 01***30 | Bolt, Mounting - Front Hand Rails | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Oil Filler(#26221255-26230516)
| 01***25 | Bolt | 2 |
| 01***30 | Bolt, Mounting - Front Hand Rails | 2 |
| 01***25 | Bolt,(With Corrosion Resistor) | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Oil Filler(#26230517-)
| 01***25 | Bolt | 2 |
| 01***25 | Bolt, Mount Engine Oil Drain To Fuel Tank | 2 |
| 01***30 | Bolt, Mounting - Front Hand Rails | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Oil Level Sensor And Oil Gauge(#26217579-26217580)
| 01***12 | Bolt,(Without R.P.C.U.) | 3 |
| 01***08 | Washer | 3 |
| 07***23 | O-Ring,(F4350-61a1b-29 ) | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Oil Level Sensor And Oil Gauge(#26217581-26238641)
| 01***12 | Bolt,(Without R.P.C.U.) | 3 |
| 01***08 | Washer | 3 |
| 04***10 | Clip | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Oil Level Sensor And Oil Gauge(#26238642-)
| 01***12 | Bolt - Front Cover Mounting | 3 |
| 01***08 | Washer | 3 |
| 04***10 | Clip | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Oil Pan And Suction Tube (With Drain Plug)(#26219448-)
| 07***16 | Gasket,(For Pc750-6) (See Fig.A2110) | 1 |
| 09***50 | Liquid Gasket, Lg-7, 150g | 0 |
| 62***80 | Plug,Drain | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Oil Pan And Suction Tube (Without Drain Plug)(#26200929-26222493)
| 09***50 | Liquid Gasket, Lg-7, 150g | 0 |
| 67***10 | Gasket (K2) | 1 |
| 67***30 | Bolt, Hex Cap (M8-1.25x30) | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Oil Pan And Suction Tube (Without Drain Plug)(#26217579-26219447)
| 09***50 | Liquid Gasket, Lg-7, 150g | 0 |
| 67***70 | Plate, Clamping | 1 |
| 67***10 | Gasket (K2) | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Oil Pan Bolt(#26204449-)
| 67***60 | Bolt, Mounting (M8-1.25x25) | 3 |
| 67***10 | Bolt, Mounting (M8-1.25 X 25) | 33 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Oil Pressure Switch(#26200929-26222207)
| 67***30 | Cartridge, Engine Oil Filter | 2 |
| 67***40 | Switch,Oil Pressure | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Oil Pressure Switch(#26222208-)
| 08***05 | Switch,Engine Oil Pressure | 1 |
| 62***10 | Seal, O-Ring (M10-1.00) | 1 |
| 67***30 | Cartridge, Engine Oil Filter | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Oil Pump(#26200939-26273427)
| 67***10 | Oil Pump Ass'Y | 1 |
| 67***11 | Pump, Lubricating Oil | 1 |
| 67***20 | Bolt (M8x1.25x30) | 4 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Oil Pump(#26273428-)
| 67***11 | Pump, Lubricating Oil | 1 |
| 67***20 | Bolt (M8x1.25x30) | 4 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Piston
| 67***00 | Piston Ring Ass'Y | 6 |
| 67***10 | Pin, Piston | 6 |
| 67***20 | Ring, Retaining | 12 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Rear Hanger
| 01***30 | Bolt, Mounting - Front Hand Rails | 2 |
| 67***20 | Plate Hanger | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Repair Parts (1/4) (Cylinder Head)
| 67***40 | Gasket, Cylinder Head - 0.5mm Os | 1 |
| 67***70 | Gasket, Cylinder Head - 0.25mm Os | 1 |
| 67***51 | Gasket? 0.50mm,Head | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Repair Parts (2/4) (Cylinder Block)
| 67***10 | Bushing, Oversize (No. 1 Bore) | 1 |
| 67***20 | Bushing, Oversize (No. 2-5 Bore) | 1 |
| 67***10 | Sleeve, Salvage - Std Bore | 6 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Repair Parts (3/4) (Crankshaft)
| 67***00 | Main Metal Ass'Y | 6 |
| 67***00 | Main Metal Ass'Y | 6 |
| 67***00 | Main Metal Ass'Y | 6 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Repair Parts (4/4) (Piston)
| 67***00 | Piston Ring Ass'Y | 6 |
| 67***00 | Piston Ring Ass'Y | 6 |
| 67***20 | Piston? 0.5mm | 6 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Rocker Arm
| 67***70 | Screw, Slotted Set (3/8-24x1 1/2 Inch) | 2 |
| 67***40 | Bolt | 6 |
| 67***10 | Rod, Push | 12 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Safety Relay (Forwarded Individually Parts)(#26269414-)
| 60***30 | Switch,Starter Relay | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Solenoid
| 01***70 | Screw | 1 |
| 01***20 | Bolt,(With Tachometer Outlet) | 2 |
| 01***35 | Screw | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Spare Parts (For 35a Brushless Alternator)(#26237081-)
| 07***16 | Gasket,(For Pc750-6) (See Fig.A2110) | 1 |
| 67***81 | Gasket, Valve Cover | 6 |
| 67***10 | Gasket,Camfollower Cover Bolt | 6 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Starting Motor (4.5kw) (Inner Parts)(#26200929-26239105)
| 60***10 | Starting Motor Ass'Y,(4.5kw) | 1 |
| ND***82 | Yoke Assembly | 1 |
| ND***00 | Washer, Felt | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Starting Motor (4.5kw) (Inner Parts)(#26239106-)
| 60***10 | Starting Motor Ass'Y,(4.5kw) | 1 |
| ND***82 | Yoke Assembly | 1 |
| ND***00 | Washer, Felt | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Starting Motor (4.5kw)(#26200929-26239105)
| (6***0) | Starting Motor Ass'Y,(4.5kw) (See Fig.A621p-02a2) | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Starting Motor (4.5kw)(#26239106-)
| (6***0) | Starting Motor Ass'Y,(4.5kw) (See Fig.A621p-02a2) | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Starting Motor Mounting (4.5kw)(#26236989-)
| 01***35 | Bolt, Mount Bracket To Floor | 2 |
| 67***11 | Gasket,Starter | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Starting Motor Mounting(#26200939-26236988)
| 67***11 | Gasket,Starter | 1 |
| 67***20 | Bolt, Mounting (M10x1.50x35) | 2 |
| 67***10 | Bolt (M10x1.50x35) | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Tachometer Adapter(#26206782-26217578)
| 67***20 | Seal, Rectangular Ring | 1 |
| 67***50 | Washer | 2 |
| 67***10 | Adapter | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Tachometer Adapter(#26217579-26237080)
| 67***20 | Seal, Rectangular Ring | 1 |
| 67***30 | Adapter | 1 |
| 67***50 | Washer | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Tachometer Drive Cover(#26237081-)
| 67***90 | Cover, Mechanical Tach Drive | 1 |
| 67***20 | Seal, Rectangular Ring | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Tappet
| 67***12 | Tappet, Valve | 12 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Thermostat
| 67***20 | Thermostat | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Thermostat Housing
| 07***25 | Clip,(For Slag Handling) | 1 |
| 67***40 | Bolt, (M8x1.25x35) | 1 |
| 67***70 | Coupling, Plain Hose | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Turbocharger Mounting(#26200929-26232772)
| 67***10 | Stud ((M10x1.50 (Both Ends) X42)) | 4 |
| 67***20 | Nut (M10x1.50) | 4 |
| 67***30 | Gasket, Turbocharger Mounting | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Turbocharger Mounting(#26232773-)
| 67***10 | Stud ((M10x1.50 (Both Ends) X42)) | 4 |
| 67***20 | Nut (M10x1.50) | 4 |
| 67***31 | Kit,Turbocharger | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Turbocharger Oil Piping(#26200929-26238405)
| 67***80 | Connector, Male | 2 |
| 67***30 | O-Ring,Turbocharger Drain | 2 |
| 67***20 | Gasket | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Turbocharger Oil Piping(#26238406-)
| 07***59 | Clamp - Drain Hose | 2 |
| 62***90 | Gasket,Turbocharger Oil Drain | 1 |
| 67***50 | O-Ring,Turbocharger Drain | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Under Plate
| 67***50 | Plate | 1 |
| 67***51 | Plate, Cylinder Block Stiffener | 1 |
| (0***0) | Liquid Gasket, Lg-7, 150g | 0 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Water Connector
| 67***60 | Connection, Water Inlet | 1 |
| 67***10 | Connector | 1 |
| 67***20 | Bolt (M10-1.50x75) | 3 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Water Connector Plug
| 67***10 | Plug, Pipe (1/2-14 Npt) | 2 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Water Pump
| 67***60 | Bolt (M8x1.25x22) | 2 |
| 67***00 | Water Pump Ass'Y | 1 |
| 67***01 | Water Pump Ass'Y | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Water Pump (Hardening Pulley)
| 67***60 | Bolt (M8x1.25x22) | 2 |
| 67***00 | Water Pump Ass'Y | 1 |
| 67***01 | Water Pump Ass'Y | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Water Temperature Sensor Adapter(#26206782-)
| 07***12 | Washer, Gasket,(Without Thermo Sensor) (K1) | 1 |
| 51***81 | Adapter, Reducing | 1 |
| 61***40 | Screw | 1 |
Komatsu : Gd521a-1e(S/N 12001-Up) : S6d102e-1t Engine S/N 26200929-Up : Water Temperature Sensor(#26217494-)
| 08***14 | Clip,(For Slag Handling) (For Usa) | 1 |
| 08***10 | Connector, Clip | 1 |
| 78***80 | Sensor,Water Temperature | 1 |
Wheel
Komatsu : Gd521a-1e(S/N 12001-Up) : Wheel : Wheel And Tubed Tire
| 23***20 | Valve,Stem | 1 |
| 23***40 | O-Ring | 1 |
| 23***20 | Ring,Side | 1 |
GD521A-1E(S/N 12001-UP) serial number reference
The PIN plate for the GD521A-1E motor grader is located on the cab pillar or front frame near the front axle. The prefix is the first three characters of the 17-character ISO PIN found on the emissions/export plate.
| Prefix | Identifies | Notes |
|---|---|---|
| GD521A-1E | GD521A-1E | S/N 12001-UP. Engine: S6D102E-2 (Emission). Source: published references catalog listing for GD521A-1E S/N 12001-UP. No other prefixes found for this specific serial range in the provided text. |
Frequently asked questions
What engine does the GD521A-1E (S/N 12001-UP) use?
The GD521A-1E (S/N 12001-UP) uses the Komatsu S6D102E-2 diesel engine.
What is the operating weight of the GD521A-1E?
Operating weight varies by configuration, ranging from 10,800 kg to 15,000 kg.
What model replaced the GD521A-1 series?
The GD521A-1 series was succeeded by the GD521-2 series motor graders.
What GD521A-1E(S/N 12001-UP) owners discuss
What engine powers the GD521A-1E (S/N 12001-UP) and what are the common powertrain or hydraulic behaviors noted for this series?
The GD521A-1E (S/N 12001-UP) utilizes the Komatsu SA6D140E-2 diesel engine. Community consensus for this series highlights that hydraulic performance is heavily dependent on maintaining strict engine RPM under load; if the engine drops significantly when hydraulics are engaged, the hydraulic system is likely dragging the engine down rather than suffering from internal pump failure. Common powertrain behaviors include sensitivity to transmission clutch wear, with slipping in forward or reverse clutches often indicating operational abuse or setting errors rather than immediate mechanical failure. Hydraulic weakness that appears only when the machine is hot typically points to internal leakage in the main pump, control valve, or cylinders due to decreased oil viscosity, rather than a pump failure alone. Cold starts and initial hydraulic response are critical indicators of system health before viscosity drops.
What are the typical undercarriage wear patterns and maintenance considerations for the GD521A-1E motor grader?
Undercarriage wear on the GD521A-1E is accelerated by continuous operation in dusty environments and high-load grading. Key wear points include track rollers, idlers, and drive sprockets, which require regular tension checks to prevent track loosening. Mud or debris packed into the undercarriage can cause mechanical resistance and uneven track wear. Operators should monitor track tension closely, as repeated loosening often indicates issues with the tensioner or excessive wear in the track chain links. Regular inspection of the final drives for noise and oil contamination is essential, as final drive failure is often preceded by oil level drops or contamination from external sources. Proper track tension and clean undercarriage components are critical for maintaining travel speed and preventing side-to-side pulling.
What are the known engine quirks and sensor issues for the GD521A-1E series?
Engine quirks for the GD521A-1E include sensitivity to air and fuel filter condition, with power loss under load often stemming from restricted airflow or fuel delivery rather than injector failure. Common sensor issues involve the charge air pressure sensor, coolant temperature sensor, and engine oil pressure sensor, which can trigger derating or shutdown alarms if they fail or provide out-of-range signals. The engine control module (ECM) is susceptible to intermittent faults from unstable power supplies or poor grounds, leading to random shutdowns or dashboard failures. Operators should verify battery charge and ground connections before diagnosing complex engine faults, as low voltage can mimic sensor failures. Regular cleaning of the cooling package (radiator, hydraulic oil cooler, charge-air cooler) is vital to prevent overheating, as dust and debris accumulation between heat exchangers can cause marginal cooling capacity issues.
What are the common electrical and diagnostic challenges for this machine?
Electrical challenges for the GD521A-1E often stem from the complexity of the KOMNET datalink and KDOC systems. Common issues include datalink timeouts, sensor supply voltage errors (low or high), and intermittent communication failures between the ECM and other control modules. Fault codes related to injector circuits, turbo speed sensors, and EGR valve positions are frequent and require systematic diagnosis to distinguish between sensor faults and actual mechanical issues. Operators should check for loose connectors, corroded pins, and damaged wiring harnesses, especially in areas exposed to vibration and moisture. Intermittent starting and dashboard failures are often linked to battery charge state and main starter cable integrity, so voltage-drop tests under load are recommended before replacing starters or sensors.
What specific items should be checked when buying a used GD521A-1E (S/N 12001-UP)?
When purchasing a used GD521A-1E (S/N 12001-UP), verify the engine serial number to confirm the SA6D140E-2 engine and check for any history of major overhauls. Inspect the undercarriage for excessive wear on track rollers, idlers, and drive sprockets, and ensure track tension is correct. Test all hydraulic functions for smooth operation, paying attention to performance when cold versus hot to identify internal leakage. Check for any active or persistent fault codes in the ECM, particularly those related to the transmission clutches, turbo speed, and sensor supply voltages. Verify the condition of the cooling package, ensuring no debris is packed between the radiators and coolers. Finally, confirm the integrity of the battery, main starter cable, and ground connections, as electrical issues can mimic more serious mechanical failures.
What safety-critical fixes or inspections are recommended for the GD521A-1E?
Safety-critical inspections for the GD521A-1E include verifying the proper operation of the parking brake and travel interlocks, as well as checking the integrity of the safety lockout mechanisms. Ensure that all hydraulic hoses and fittings are in good condition to prevent high-pressure fluid injection injuries. Inspect the operator's cab for proper ventilation and air conditioning function, as overheating can lead to operator fatigue and accidents. Verify that all lights, horns, and warning devices are functional. Have your dealer verify the calibration of the engine control module and the accuracy of critical sensors such as the coolant temperature and oil pressure sensors, as inaccurate readings can lead to unsafe operating conditions.
Compiled from owner and technician discussions across the industry — experiences vary by serial range and machine history.
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