Komatsuwheel loadersmall ( - wa120 / sk*)
Komatsu WA120-1LC(S/N A20001-UP)
Maintenance schedule, common problems & OEM parts breakdown
The Komatsu WA120-1LC (S/N A20001-UP) is a mid-size articulated wheel loader manufactured between 1987 and 1994. It succeeds the WA120-1 base model and is part of the WA120 series lineage, which was later replaced by the WA120-3. The machine weighs approximately 8 tons (8,818 lb) and is powered by a Komatsu S4D102E-1 diesel engine. Configurations include standard and long reach boom options, with bucket capacities ranging from 1.2 to 1.7 m³ (1.57 to 2.25 yd³). The WA120-1LC variant specifically denotes the long chassis configuration within the first generation of the WA120 family.
Across the WA120 series, the primary evolution moved from the two-speed transmission of the WA120-1 to the four-speed transmission introduced in the WA120-3 series. The WA120-1LC remains relevant in the used and parts market due to its robust, simple mechanical design and the availability of genuine Komatsu components for its S4D102E-1 engine and hydraulic systems. Its enduring presence in aggregate handling and light construction applications ensures steady demand for service manuals, undercarriage parts, and engine rebuild kits.
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 WA120-1LC(S/N A20001-UP) specifications
Engine
| Model | S4D102E-1 |
| Number of Cylinders | 4 |
| Displacement | 298.5 cu in (4890 cm³) |
| Gross Power | 63 hp (47 kW) @ 2400 rpm |
Weights
| Operating Weight | 16,953.6 lb (7690 kg) |
| Static Tipping Weight | 13,889.2 lb (6300 kg) |
Dimensions
| Transport Length | 19.9 ft (6.07 m) |
| Transport Width | 7.39 ft (2.25 m) |
| Transport Height | 10.06 ft (3.07 m) |
| Wheelbase | 8.54 ft (2.60 m) |
| Ground Clearance | 1.28 ft (0.39 m) |
Performance
| Max Speed - Forward | 21.5 mph (34.6 km/h) |
| Max Speed - Reverse | 21.8 mph (35.1 km/h) |
| Breakout Force | 13,490 lb (60.01 kN) |
| Rear Axle Oscillation | 24 degrees |
Service capacities (summary)
| Fuel Capacity | 35.2 gal (133 L) |
| Hydraulic Pump Flow | 30.4 gal/min (115 L/min) |
Values vary by configuration, region, and serial range — confirm against your machine before planning transport or lifts.
Komatsu WA120-1LC(S/N A20001-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 WA120-1LC(S/N A20001-UP) beyond the schedule
Predictive Maintenance & Fluid Analysis
Monitor hydraulic oil particle count and viscosity at 500-hour intervals to detect pump wear early. Check coolant SCA concentration every 500 hours to prevent liner cavitation in the S4D102E-1 engine. Inspect transmission oil for metal content at 1,000 hours to assess torque converter and gear health. Use Komatsu EO-15 or equivalent engine oil to maintain proper viscosity for turbocharger bearing protection. Track fuel filter replacement intervals to prevent injector contamination. Analyze axle oil samples at 2,000 hours to identify final drive gear wear before catastrophic failure occurs.
Corrective & Common Repairs
Address frequent hydraulic hose leaks at the boom cylinder fittings by replacing O-rings and inspecting hose abrasion. Replace worn bucket teeth and cutting edges to maintain digging efficiency and reduce stress on the Z-bar linkage. Repair steering cylinder seals to correct articulation drift and ensure safe maneuvering. Replace fan belt tensioner bearings if squealing occurs during engine operation. Fix air intake system leaks to prevent dust ingestion into the turbocharger. Inspect and replace worn brake discs to maintain stopping power on wet surfaces.
Overhaul & Rebuild Points
Rebuild the S4D102E-1 engine at 10,000 hours or when compression drops below specification. Replace turbocharger rotor if excessive play is detected during the 4,000-hour inspection. Overhaul the transmission case at 10,000 hours, replacing seals, gaskets, and worn gears. Rebuild the hydraulic pump if flow rates drop below 80% of original specifications. Inspect the final drive planetary gears for pitting or spalling during axle oil changes. Replace the vibration damper on the crankshaft if harmonic resonance causes excessive engine noise.
Seasonal & Environment Servicing
In cold weather, use low-viscosity engine oil and ensure coolant concentration provides adequate freeze protection. Drain water from the fuel-water separator daily to prevent fuel line icing. In dusty environments, clean the radiator fins frequently and check the air filter restriction indicator more often. In high-humidity conditions, inspect the battery electrolyte level and clean terminals to prevent corrosion. Use Komatsu TO-1 or equivalent hydraulic oil in hot climates to maintain proper viscosity. Check the air conditioner condenser for debris to ensure effective cab cooling.
WA120-1LC(S/N A20001-UP) common service parts
| Part number | Part | Notes | |
|---|---|---|---|
| 07281-00197 | Clamp,(With Pre-Fuel Filter) | Fuel system service | Check fitment → |
| 1129 112 C1 | Element, Air Cleaner - Safety | Air intake service | Check fitment → |
| 07000-02075 | O-Ring,Steering Oil Filter | Lubrication service | Check fitment → |
| 416-15-05130 | Service Kit, Transmission Oil Filter | Lubrication service | Check fitment → |
| 348 828 C1 | Nipple, Safety Filter | Scheduled service item | Check fitment → |
Always confirm against your machine's serial number — cross-check any part in Heavy Parts AI before ordering.
WA120-1LC(S/N A20001-UP) fault codes & troubleshooting
| Code | Meaning | Likely cause | What to do |
|---|---|---|---|
| E10 | Engine controller power failure or engine control drive system circuit malfunction. | Faulty ECM power connections, blown fuses, or damaged ground wires. | Inspect ECM power connections, fuses, and ground wires for continuity and corrosion. |
| E11 | Engine control system failure; output power reduced to protect the engine. | Critical engine parameters exceeded, such as high coolant temperature, low oil pressure, or restricted air intake. | Check coolant temperature, engine oil pressure, and air filter condition. |
| CA115 | Engine speed sensor and backup speed sensor failure. | Broken crankshaft speed sensor, wiring harness damage, or corroded pin connectors. | Replace the speed sensor and verify voltage at the pin connector. |
| CA122 | Intake air pressure sensor feedback voltage too high. | Faulty intake pressure sensor or shorted wiring. | Verify the intake pressure sensor operation and inspect wiring for shorts. |
| CA123 | Intake air pressure sensor feedback voltage too low. | Sensor short to ground or significant airflow restriction upstream of the sensor. | Check for sensor short circuits and inspect for airflow restrictions. |
| CA153 | Intake air temperature sensor feedback voltage too high. | Faulty intake air temperature (IAT) sensor or open circuit in the sensor harness. | Test the IAT sensor and replace if out of specification. |
| CA154 | Intake air temperature sensor feedback voltage too low. | Shorted IAT sensor or damaged wiring harness. | Replace or test the IAT sensor for proper resistance values. |
| CA441 | Battery voltage too low. | Weak battery, failing alternator, or loose charging system connections. | Replace the battery or alternator; check the voltage regulator and charging belt. |
| CA442 | Battery voltage too high. | Faulty voltage regulator or alternator overcharging. | Replace the alternator or battery; check the voltage regulator. |
| B@BCNS | Engine coolant overheating. | Low coolant level, blocked radiator fins, or failed fan belt. | Check radiator fins for debris, inspect fan belt tension, and verify coolant level. |
Codes and remedies are general guidance for this model family — always confirm with diagnostic tooling and your dealer before major repairs.
WA120-1LC(S/N A20001-UP) attachments & work tools
Standard Buckets
General-purpose and light-material buckets are the primary work tools for this class. Factory specifications for the WA120-1 series indicate a heaped capacity of 1.2 cubic meters (1.57 cubic yards) and a struck capacity of 1.2 cubic meters (1.57 cubic yards). The bucket width is specified at 2.39 meters (7.85 feet). Variations in capacity exist across the WA120 family, ranging from 1.3 to 1.7 cubic meters (1.7 to 2.25 cubic yards) for later models, but the WA120-1 base configuration centers on the 1.2 cubic meter rating.
Coupler Systems
The machine utilizes a standard quick-coupler mounting system for rapid tool interchange. Parts catalogs for the WA120-1 and WA120 series list 'Coupler' as a distinct attachment category component. This system allows for the mechanical connection of various buckets and specialized tools without manual pinning.
Hydraulic Kits
Attachment operation requires specific hydraulic kit configurations. Parts listings for the WA120-1 and WA120 series explicitly include 'Hydraulic Kit' under the Attachments category, indicating that auxiliary hydraulic circuits are necessary to power couplers or specialized tool functions. The exact kit configuration varies by the specific tool selected and the machine's factory hydraulic arrangement.
Cutting Edges & Wear Parts
Standard front loader buckets are equipped with replaceable cutting edges. Parts catalogs for the WA120-1 and WA120 series list 'Cutting Edge' as a standard attachment component. These wear parts are essential for maintaining bucket performance and are available as direct replacements for the WA120-1 frame.
Guarding & ROPS
The operator's cab includes ROPS (Roll-Over Protective Structure) guarding as a standard factory configuration. Parts listings for the WA120-1 series identify 'ROPS' as a cab component. This guarding is integrated into the cab shell structure to protect the operator during tipping events or falling object impacts.
All WA120-1LC(S/N A20001-UP) assemblies by section
Every catalogued assembly group for the Komatsu WA120-1LC(S/N A20001-UP). Open an assembly to preview the parts inside — full OEM part numbers are available in Heavy Parts AI.
Drive Shaft
Komatsu : Wa120-1lc(S/N A20001-Up) : Drive Shaft : Axle Assembly Front
| 01***25 | Bolt, Housings To Differential | 28 |
| 01***45 | Washer,(For Travel Motor) (Not Show) | 28 |
| 04***60 | Screw, Serial Number Plate | 4 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Drive Shaft : Axle Assembly Front And Rear Final Drive And Wheel Brake
| 01***85 | Bolt | 4 |
| 01***60 | Washer,(Without Rops Guard? Canopy) | 48 |
| 41***50 | Spacer | 4 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Drive Shaft : Axle Assembly Front Differential
| 01***30 | Capscrew - M12 X 1.75 | 28 |
| 01***35 | Bolt, Mount Carrier | 6 |
| 01***45 | Capscrew - M16 | 12 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Drive Shaft : Axle Assembly Rear
| 01***25 | Bolt, Housings To Differential | 28 |
| 01***45 | Washer,(For Travel Motor) (Not Show) | 28 |
| 04***60 | Screw, Serial Number Plate | 4 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Drive Shaft : Axle Assembly Rear Differential
| 01***30 | Capscrew - M12 X 1.75 | 28 |
| 01***35 | Bolt, Mount Carrier | 1 |
| 01***45 | Capscrew - M16 | 12 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Drive Shaft : Brake Oil Piping Brake Reservoir To Master Cylinder
| 01***25 | Bolt,Without Revolution Sensor | 2 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 3 |
| 01***23 | Washer, Wiring Harness Mounting Bracket | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Drive Shaft : Brake Oil Piping Master Cylinder To Front Axle
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 4 |
| 01***32 | Washer,(With Auto Emergency Steering) | 4 |
| 07***23 | O-Ring,(F4350-68a0 -13 ) | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Drive Shaft : Brake Oil Piping Master Cylinder To Rear Axle
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 1 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 2 |
| 01***45 | Bolt,(For Power Tilt Mech Angle) | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Drive Shaft : Brake Pedal And Linkage
| 01***16 | Bolt (With Air Heater & Conditioner) | 4 |
| 01***40 | Bolt, Mount Master Brake Cylinder | 4 |
| 01***20 | Bolt,(Without Rops Guard? Canopy) | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Drive Shaft : Drive Shaft Center
| 01***45 | Screw | 8 |
| 41***12 | Shaft Assembly, Center Drive | 1 |
| 41***20 | Spider Assembly | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Drive Shaft : Drive Shaft Front
| 01***55 | Screw | 4 |
| 01***10 | Screw | 1 |
| 01***45 | Screw | 4 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Drive Shaft : Drive Shaft Rear
| 01***45 | Screw | 8 |
| 41***20 | Spider Assembly | 2 |
| 41***30 | Fitting, Grease | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Drive Shaft : Master Brake Cylinder
| 41***00 | Service Kit,Brake Master Cylinder | 1 |
| 41***01 | Cylinder Assembly, Master Brake | 1 |
| 41***10 | Piston,Secondary (Kit) | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Drive Shaft : Parking Brake
| 04***10 | Pin,Cotter? (For Ripper) | 1 |
| 41***10 | Kit, Parking Brake Pad | 1 |
| 41***00 | Caliper Assembly, Parking Brake | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Drive Shaft : Parking Brake Control
| 01***20 | Bolt,(Used When Towing Winch) | 2 |
| 01***30 | Bolt,Radio Controlled Slag Handling | 6 |
| 01***16 | Washer,(With Water Separator) | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Drive Shaft : Parking Brake Mounting Parts
| 01***55 | Bolt,(For France Noise Suppression) | 4 |
| 01***32 | Washer,(Not Used With Emergency Str.) | 4 |
| 41***30 | Bracket, Caliper Mounting | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Drive Shaft : Tires And Wheels - 15.5 X 25 (One Piece Rim)
| 17***H1 | Valve Assembly | 4 |
| 41***20 | Wheel Assembly, 15.5 X 25 (One Piece Rim) | 4 |
| 61***91 | Valve, Tire Air | 4 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Drive Shaft : Tires And Wheels - 15.5 X 25 (Three Piece Rims)
| 12***60 | Ring, Lock | 1 |
| 14***H1 | O-Ring - Rim | 4 |
| 16***34 | Flange, Side | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Drive Shaft : Tires And Wheels - 17.5 X 25 (One Piece Rim)
| 17***H1 | Valve Assembly | 4 |
| 41***40 | Wheel Assembly, 17.5 X 25 (One Piece Rim) | 4 |
| 61***91 | Valve, Tire Air | 4 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Drive Shaft : Tires And Wheels - 17.5 X 25 (Three Piece Rims)
| 12***60 | Ring, Lock | 1 |
| 14***H1 | O-Ring - Rim | 4 |
| 30***R1 | Flange, Side | 1 |
Engine
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine : Accessories
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine : Cooling System
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine : Cylinder Block
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine : Cylinder Head
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine : Electrical System
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine : Engine Mounting
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine : Fuel System
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine : Gasket Sets And Repair Kits
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine : Lubricating Oil System
Engine Related Parts & Electrical System
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Accelerator Linkage
| 01***20 | Bolt,(Without Maintenance Monitor) | 3 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 2 |
| 01***05 | Nut,(For Air Conditioner Less), Nut | 6 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Accelerator Pedal
| 01***16 | Bolt, Mount Washer Tank To Bracket, Bolt | 2 |
| 01***60 | Bolt,(For Japan And Sweden) | 1 |
| 01***06 | Nut,(With Back-Up Alarm) (Op), Nut; Was 01580-10806 | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Air Cleaner And Connections
| 10***04 | Nipple - 1/8 X 3/4 In. Pipe | 1 |
| 11***C1 | U-Bolt, 5/16nc | 1 |
| 11***C1 | Clamp, Air Intake Stack | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Air Cleaner Assembly
| 11***C1 | Valve, Air Cleaner Vacuator | 1 |
| 11***C1 | Element, Air Cleaner - Safety | 1 |
| 12***H1 | Nut Assembly, Wing | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Alternator
| 12***H1 | Bushing, Mounting Hinge | 1 |
| 12***H1 | Bolt, Field Coil And Support | 4 |
| 12***H1 | Bearing, Ball | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Battery And Battery Box
| 01***30 | Bolt,(Cold Terrain Spec.) | 1 |
| 01***20 | Bolt,(Large Capacity Type) (Std) | 2 |
| 01***40 | Bolt,(Dust And Dirt Protection) | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Cranking Motor - 27mt
| 11***33 | Nut | 2 |
| 12***17 | Washer, Shunt Lead To Switch Attaching | 2 |
| 12***21 | Screw | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Cranking Motor - 28mt
| 12***91 | Motor Assembly, Cranking | 1 |
| 14***H1 | Solenoid | 1 |
| 14***H1 | Drive, Clutch | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Cranking Motor Mounting
| 01***35 | Bolt, M10 X 35 12 Pt - Cranking Motor Mounting | 3 |
| 12***H1 | Gasket, Starting Motor | 1 |
| 44***C1 | Gasket, Liquid | 0 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Electrical System (Engine Line)
| 01***20 | Bolt,(Sandy? Dusty Terrain Spec.) | 6 |
| 01***25 | Bolt,(Without Auto Priming System) | 2 |
| 01***16 | Bolt,(Sandy And Dusty Spec.) | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Electrical System (For Cab)
| 01***80 | Bolt,(See Fig.0131) | 2 |
| 01***20 | Screw | 2 |
| 01***08 | Washer,(For 1 Attachment And Pat) | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Electrical System (Front)
| 01***12 | Bolt (M8-1.25x12) | 2 |
| 01***16 | Bolt,(Sandy And Dusty Spec.) | 1 |
| 01***20 | Bolt,(Large Capacity Type) (Std) | 20 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Electrical System (Ground Driven Steering)
| 01***12 | Bolt,(Without R.P.C.U.) | 1 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 4 |
| 01***23 | Washer,(With Auto Emergency Steering) | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Electrical System (Rear)
| 01***20 | Bolt,(Large Capacity Type) (Std) | 5 |
| 01***12 | Bolt, Bolt,(No Need To Quick Shift) | 6 |
| 01***20 | Bolt,(With Auto Emergency Steering) | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Electrical System Rops Cab
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Engine Fan And Mounting
| 01***90 | Bolt, Fan Mounting | 4 |
| 01***32 | Washer,(With Auto Emergency Steering) | 4 |
| 12***H1 | Spacer, Fan Pilot | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Engine Mounting Parts
| 01***50 | Bolt, Radiator To Frame | 8 |
| 01***35 | Bolt, Bolt, Mount Tubes To Switch And Work Pumps | 6 |
| 01***30 | Bolt, Mount Engine To Frame | 4 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Engine Oil Drain Line
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Ether Start And Mounting
| 01***20 | Bolt,(With Auto Emergency Steering) | 2 |
| 01***23 | Washer, Wiring Harness Mounting Bracket | 2 |
| 12***91 | Clamp, Ether Cylinder Mounting | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Exhaust Pipe (Glass Wool)
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 4 |
| 01***90 | Bolt,(Without Giant Ripper) | 1 |
| 01***10 | Nut,(Without Air Conditioner) | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Exhaust System
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Fan Guard
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 8 |
| 01***12 | Bolt,(With Speedometer) | 4 |
| 01***16 | Bolt - Starting Motor Ground Cable | 8 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Front Driving Light
| 42***02 | Light Assembly - Front Driving | 2 |
| 42***10 | Bulb - 85/65 W | 1 |
| 42***20 | Cushion | 4 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Fuel Tank And Piping
| 01***20 | Bolt,(Sandy? Dusty Terrain Spec.) | 2 |
| 01***16 | Bolt,(Sandy And Dusty Spec.) | 1 |
| 01***35 | Bolt - Torque Converter Totransmission Mounting | 4 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Instrument Panel
| 01***10 | Bolt, Mount Flasher | 1 |
| 01***20 | Screw | 2 |
| 01***19 | Washer,Spring (With Extinguisher) (D31p) | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : L.H. Turn Signal And Parking Light
| 01***16 | Screw - Mounting | 2 |
| 01***50 | Screw - Mounting | 2 |
| 01***05 | Washer - Mounting | 4 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : R.H. Turn Signal And Parking Light
| 01***16 | Screw - Mounting | 2 |
| 01***50 | Screw - Mounting | 2 |
| 01***05 | Washer - Mounting | 4 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Radiator And Mounting
| 01***16 | Bolt (With Air Heater & Conditioner) | 8 |
| 01***45 | Bolt, Mounting Bracket To Radiator (Top) | 2 |
| 01***65 | Bolt, Mount Radiator To Frame (Bottom) | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Radiator Piping
| 01***30 | Bolt,(For Mechanical Governor) | 1 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 1 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Rear Work Light
| 22***0M | Bulb - 70w | 1 |
| 42***20 | Cushion | 4 |
| 42***02 | Light Assembly - Rear Work | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Engine Related Parts & Electrical System : Speedometer
| 01***20 | Bolt,(Large Capacity Type) (Std) | 4 |
| 01***32 | Washer,(With Auto Emergency Steering) | 4 |
| 08***23 | Band,(With Water Separator) | 1 |
Frame
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Additional Counterweight
| 01***55 | Bolt, Strut Mounting - To Radiator And Rear Frame | 4 |
| 01***60 | Flat Washer - M20 (Hardened) | 4 |
| 41***41 | Weight,Counter? L.H.160kg | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Canvas Canopy
| 01***60 | Bolt, Mount Pole | 4 |
| 01***32 | Washer | 8 |
| 01***60 | Washer,(Without Rops Guard? Canopy) | 4 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Dashboard
| 01***10 | Bolt,(With Auto Emergency Steering) | 4 |
| 01***16 | Bolt (With Air Heater & Conditioner) | 4 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Defroster Piping
| 01***16 | Bolt, Mount Washer Tank To Bracket, Bolt | 4 |
| 01***16 | Bolt (With Air Heater & Conditioner) | 10 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 3 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Engine Hood And Side Cover (Insulation)
| 41***10 | Sheet | 1 |
| 41***20 | Sheet | 1 |
| 41***30 | Insulation | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Engine Hood And Side Covers
| 01***10 | Bolt,(With Auto Emergency Steering) | 4 |
| 01***16 | Bolt (With Air Heater & Conditioner) | 4 |
| 01***20 | Bolt,(With Auto Emergency Steering) | 10 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Fenders And Ladders (With Rops Cab)
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 18 |
| 01***30 | Bolt,(Not Used With Emergency Str.) | 4 |
| 01***35 | Bolt, Bolt, Mount Tubes To Switch And Work Pumps | 12 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Floor Frame (With Rops Cab)
| 01***35 | Bolt - Torque Converter Totransmission Mounting | 4 |
| 01***16 | Bolt, Mount Washer Tank To Bracket, Bolt | 6 |
| 01***16 | Bolt (With Air Heater & Conditioner) | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Floor Mats
| 41***60 | Sheet (W/O Heater Unit) | 1 |
| 41***70 | Sheet (W/Heater Unit) | 1 |
| 41***11 | Mat, Floor (W/Rops Canopy) | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Front Frame
| 01***30 | Bolt,(For France Noise Suppression) | 4 |
| 01***30 | Bolt,Radio Controlled Slag Handling | 9 |
| 01***80 | Bolt, Mount Cab To Rear Frame | 8 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Guard And Hand Rails For Machines With Rops Canopy
| 01***25 | Bolt,(Without Auto Priming System) | 4 |
| 01***30 | Bolt,Radio Controlled Slag Handling | 10 |
| 01***35 | Bolt - Torque Converter Totransmission Mounting | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Heater Assembly Eagle - S/N A20158 And Up
| 14***H1 | Valve, Heater | 1 |
| 41***20 | Housing, Top And Bottom | 1 |
| 41***30 | Motor Assembly | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Heater Assembly Komatsu - S/N A20001 Thru A20157
| 01***08 | Screw, Control Lever Rod | 1 |
| 41***22 | Heater Unit Ass'Y | 1 |
| 41***60 | Switch, Heater | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Heater Mounting Parts Eagle - S/N A20158 And Up
| 01***16 | Bolt, Mount Washer Tank To Bracket, Bolt | 2 |
| 01***25 | Bolt,Without Revolution Sensor | 4 |
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Heater Mounting Parts Komatsu - S/N A20001 Thru A20157
| 01***16 | Bolt, Mount Washer Tank To Bracket, Bolt | 2 |
| 01***25 | Bolt,Without Revolution Sensor | 2 |
| 01***19 | Washer,Spring (With Extinguisher) (D31p) | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Heater Piping Eagle - S/N A20158 And Up
| 07***59 | Clamp,See Fig. K4010-05a0 | 4 |
| 30***91 | Valve, Shut-Off | 2 |
| 36***C1 | Heater Assembly (See Fig. K5280-01a3) | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Heater Piping Komatsu - S/N A20001 Thru A20157
| 01***12 | Bolt, Bolt,(No Need To Quick Shift) | 14 |
| 01***16 | Bolt, Mount Washer Tank To Bracket, Bolt | 5 |
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 3 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Instrument Panel Cover
| 01***30 | Bolt,(For Quick Shift) (Mitsubishi) | 2 |
| 01***05 | Nut,(For Air Conditioner Less), Nut | 4 |
| 01***11 | Nut,(Not Shown) | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Lubricator (Axle Support)
| 01***16 | Bolt,(Sandy And Dusty Spec.) | 1 |
| 01***32 | Washer,(With Auto Emergency Steering) | 1 |
| 07***75 | Fitting,Grease (Without Lub. Piping) | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Operator'S Seat Mounting Suspension Type (Kab)
| 01***32 | Washer,(Not Used With Emergency Str.) | 2 |
| 11***91 | Belt, Seat | 1 |
| 21***R1 | Bolt - 7/16 Nf X 1-3/4 In | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Operator'S Seat Mounting Suspension Type (Sear'S Manufacturing)
| 01***32 | Washer,(Not Used With Emergency Str.) | 4 |
| 42***00 | Arm Rest Kit | 1 |
| 42***90 | Screw, Socket Button Head - Seat Mounting | 4 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Operator'S Seat Rigid Type
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 4 |
| 01***06 | Nut,(With Back-Up Alarm) (Op), Nut; Was 01580-10806 | 4 |
| 01***23 | Washer, Wiring Harness Mounting Bracket | 4 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Operator'S Seat Suspension Assembly (Sear'S Manufacturing)
| 42***20 | Suspension Assembly | 1 |
| 42***30 | Bearing Kit | 1 |
| 42***10 | Spring, Conical | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Operator'S Seat Suspension Type (Kab)
| 20***80 | Kit, Spring - Height Riser | 1 |
| 20***10 | Kit, Damper Assembly | 1 |
| 20***20 | Suspension Assembly | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Operator'S Seat Suspension Type (Sear'S Manufacturing)
| 01***23 | Washer | 4 |
| 01***32 | Washer,(With Auto Emergency Steering) | 4 |
| 02***25 | Bolt,(Europe Spec.) | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Rear Frame
| 01***85 | Bolt | 2 |
| 01***95 | Bolt, Counterweight | 2 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 4 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Rops Cab Front Glass, Wiper, And Lights
| 01***20 | Bolt,(Without Maintenance Monitor) | 6 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 4 |
| 01***19 | Washer,Spring (With Extinguisher) (D31p) | 6 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Rops Cab Front Windshield Washer
| 08***19 | Band - Tie Hose To Wire Harness | 1 |
| 12***80 | Washer, Lock - Ground Screw | 4 |
| 12***86 | Washer, 1/4 Lock | 4 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Rops Cab Interior Trim
| 11***C2 | Fastener | 5 |
| 12***80 | Washer, Lock - Ground Screw | 2 |
| 12***91 | Light, Cab Dome | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Rops Cab Mirrors And Grab Rails
| 01***25 | Bolt,Without Revolution Sensor | 8 |
| 01***20 | Bolt | 6 |
| 01***25 | Washer,Spring?For Additional Rear Lam | 8 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Rops Cab Mounting Parts
| 01***80 | Bolt, Mount Cab To Rear Frame | 10 |
| 01***35 | Bolt | 8 |
| 01***23 | Washer | 8 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Rops Cab Rear Cab Window And Lower Panel
| 01***20 | Bolt,(Without Maintenance Monitor) | 4 |
| 01***25 | Bolt,Without Revolution Sensor | 7 |
| 01***19 | Washer,Spring (With Extinguisher) (D31p) | 4 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Rops Cab Rear Wiper Assembly
| 01***20 | Washer,Spring | 2 |
| 01***60 | Washer,Lock | 2 |
| 02***19 | Bolt | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Rops Cab Right And Left Doors
| 01***16 | Bolt, Mount Washer Tank To Bracket, Bolt | 1 |
| 01***16 | Bolt, Battery To Frame Ground Wire Attaching | 2 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 16 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Rops Canopy And Mounting
| 01***80 | Bolt, Mount Cab To Rear Frame | 10 |
| 01***60 | Washer,(Without Rops Guard? Canopy) | 10 |
| 41***10 | Canopy, Rops | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Seat Belt (For Rigid Type Seat)
| 02***19 | Bolt,Tether | 2 |
| 09***01 | Bolt,(For Shipping) | 2 |
| 09***02 | Washer,(For Shipping) | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Vandalism Protection
| 01***05 | Nut,(For Air Conditioner Less), Nut | 4 |
| 01***10 | Washer,(For 35a Alternator) | 2 |
| 01***23 | Washer,(With Auto Emergency Steering) | 8 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Wiper Motor Front Windshield
| 41***20 | Motor, Wiper | 1 |
| 41***30 | Connecting Link | 1 |
| 41***20 | Washer, Spacing | 3 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Frame : Wiper Motor Rear Window
| 41***20 | Motor, Wiper | 1 |
| 41***20 | Washer, Spacing | 3 |
| 41***30 | Nut | 1 |
Mark Plates
Komatsu : Wa120-1lc(S/N A20001-Up) : Mark Plates : Product Graphics - English
| 04***60 | Screw,Machine Model (For Ec Reg.) | 4 |
| 09***70 | Plate, Operating - Starting Switch | 1 |
| 09***04 | Plate, Operating, Hydraulic Cooler Lock | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Mark Plates : Product Graphics - French
| 04***60 | Screw,Machine Model (For Ec Reg.) | 4 |
| 09***70 | Plate? Operating,Starting Switch | 1 |
| 09***04 | Plate, Operating, Hydraulic Cooler Lock | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Mark Plates : Product Graphics - Spanish
| 04***60 | Screw,Machine Model (For Ec Reg.) | 4 |
| 09***50 | Plate? Operating,Starting Switch | 1 |
| 09***04 | Plate, Operating, Hydraulic Cooler Lock | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Mark Plates : Tools
| 07***50 | Pump, (Bellows Type) | 1 |
| 07***03 | Cartridge - Grease | 1 |
| 09***06 | Wrench Set,8x10? 12x14? 13x17? | 1 |
Steering Control System
Komatsu : Wa120-1lc(S/N A20001-Up) : Steering Control System : Check Valve For Ground Driven Steering
| 07***35 | O-Ring, At Lower Oil Cooler Inlet Port | 1 |
| 70***11 | Body | 1 |
| 70***21 | Poppet | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Steering Control System : Divider Valve For Ground Driven Steering
| 01***25 | Bolt,Without Revolution Sensor | 2 |
| 01***30 | Screw | 2 |
| 01***70 | Screw | 4 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Steering Control System : Ground Driven Steering Piping Divider Valve To Control Valve
| 01***05 | Bolt, Mount Hose Clip | 1 |
| 01***32 | Washer,(With Auto Emergency Steering) | 1 |
| 01***32 | Washer, (Without Emergency Steering) | 4 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Steering Control System : Ground Driven Steering Piping Divider Valve To Main Hydraulic Pump
| 01***40 | Bolt,(For Position Fixing) | 4 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 2 |
| 01***25 | Washer,Spring?For Additional Rear Lam | 4 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Steering Control System : Ground Driven Steering Piping Reservoir To Ground Driven Steering Pump
| 01***55 | Bolt,(For Suction? Reversible Fan) | 4 |
| 01***85 | Bolt, Mount Solenoid Valve Body | 2 |
| 01***35 | Bolt - Torque Converter Totransmission Mounting | 8 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Steering Control System : Hydraulic Piping Steering Valve To Steering Cylinders
| 01***25 | Bolt,(Sandy? Dusty Terrain Spec.) | 5 |
| 01***40 | Bolt,(Dust And Dirt Protection) | 2 |
| 01***08 | Nut, Regular Hexagon (M10-1.50) | 3 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Steering Control System : Steering Column
| 41***00 | Steering Column A.,(See Fig.4451) | 1 |
| 41***30 | Column | 1 |
| 41***40 | Shaft | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Steering Control System : Steering Cylinder - Lh
| 07***65 | O-Ring,(F5350-62a0 -14 ) | 1 |
| 07***65 | Ring,Back-Up (Kit) | 1 |
| 07***15 | Ring,Wear? Piston | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Steering Control System : Steering Cylinder - Rh
| 07***65 | O-Ring,(F5350-62a0 -14 ) | 1 |
| 07***65 | Ring,Back-Up (Kit) | 1 |
| 07***15 | Ring,Wear? Piston | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Steering Control System : Steering Pump Ground Driven Steering
| 04***24 | Pin,Dowel (For No.3 Housing) | 4 |
| 04***18 | Ring, Retaining | 1 |
| 07***00 | O-Ring,(Y1620-11a0a-11) | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Steering Control System : Steering Valve
| 41***20 | Screw | 7 |
| 41***30 | Cap, End | 1 |
| 41***40 | Gerotor | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Steering Control System : Steering Wheel
Torque Converter And Transmission
Komatsu : Wa120-1lc(S/N A20001-Up) : Torque Converter And Transmission : Torque Converter
| 01***25 | Screw | 24 |
| 01***25 | Bolt, Mount Cover | 6 |
| 01***55 | Screw | 8 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Torque Converter And Transmission : Transmission (1st Clutch)
| 06***10 | Bearing,(Wa250-1m? 1p) | 1 |
| 41***02 | Clutch Assembly, 1st | 1 |
| 41***13 | Shaft And Housing Assembly | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Torque Converter And Transmission : Transmission (2nd Clutch)
| 06***12 | Bearing,Ball | 1 |
| 41***03 | Clutch Assembly, 2nd And 3rd | 1 |
| 41***13 | Shaft And Housing Assembly | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Torque Converter And Transmission : Transmission (3rd Clutch)
| 06***10 | Bearing,(Wa250-1m? 1p) | 1 |
| 41***31 | Gear? 21 Teeth,3rd | 1 |
| 41***33 | Spring, Wave | 3 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Torque Converter And Transmission : Transmission (Complete Assembly)
| 41***40 | Transmission Ass'Y,(With Back Switch) | 1 |
| 41***90 | Transmission Assembly | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Torque Converter And Transmission : Transmission (Control Pump)
| 01***80 | Capscrew | 4 |
| 01***32 | Washer, (Without Emergency Steering) | 4 |
| 04***20 | Pin,Dowel (Welded) | 4 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Torque Converter And Transmission : Transmission (Control Valve)
| 01***35 | Bolt, Mounting - Flywheel Housing End | 2 |
| 01***40 | Bolt,(Dust And Dirt Protection) | 3 |
| 01***45 | Bolt,(For Suction? Reversible Fan) | 5 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Torque Converter And Transmission : Transmission (Forward Clutch)
| 06***10 | Bearing,(Wa250-1m? 1p) | 1 |
| 41***02 | Forward And Reverse Clutch Assembly | 1 |
| 41***31 | Gear? 38 Teeth,Forward | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Torque Converter And Transmission : Transmission (Front Case)
| 01***30 | Bolt,(For France Noise Suppression) | 12 |
| 01***35 | Bolt - Torque Converter Totransmission Mounting | 5 |
| 01***32 | Washer,(With Auto Emergency Steering) | 12 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Torque Converter And Transmission : Transmission (Output Shaft)
| 01***25 | Bolt - Rear Guard Mounting | 2 |
| 01***35 | Bolt - Torque Converter Totransmission Mounting | 12 |
| 01***10 | Bolt | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Torque Converter And Transmission : Transmission (Rear Case)
| 01***40 | Bolt,(Dust And Dirt Protection) | 4 |
| 01***30 | Bolt,Radio Controlled Slag Handling | 2 |
| 01***35 | Bolt - Torque Converter Totransmission Mounting | 18 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Torque Converter And Transmission : Transmission (Reverse Clutch)
| 06***10 | Bearing,(Wa250-1m? 1p) | 1 |
| 41***43 | Gear? 25 Teeth,Reverse | 1 |
| 41***33 | Spring, Wave | 8 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Torque Converter And Transmission : Transmission (Solenoid Valve)
| 01***15 | Bolt | 10 |
| 01***30 | Washer,Spring(Sandy?Dusty Terrain S.) | 10 |
| 04***70 | Ball,(-40 Deg. Spec.) | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Torque Converter And Transmission : Transmission Control Levers
Komatsu : Wa120-1lc(S/N A20001-Up) : Torque Converter And Transmission : Transmission Control Linkage
| 01***60 | Bolt (M10-1.50x60) | 2 |
| 01***05 | Nut,L.H. Thread (D31s) | 2 |
| 01***06 | Nut, Regular Hexagon (M8-1.25) | 6 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Torque Converter And Transmission : Transmission Oil Filter
| 07***23 | O-Ring,(F4350-68a0 -13 ) | 1 |
| 07***09 | Plug, Oil Drain | 1 |
| 41***00 | Filter Assembly (See Pg F-058) | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Torque Converter And Transmission : Transmission Piping
| 01***35 | Bolt,(Without Auto Priming System) | 4 |
| 01***25 | Bolt,(Sandy? Dusty Terrain Spec.) | 3 |
| 01***30 | Bolt,(For France Noise Suppression) | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Torque Converter And Transmission : Transmission Service Kit
| 07***65 | O-Ring,Injection Pump Case | 1 |
| 07***75 | O-Ring,Steering Oil Filter | 1 |
| 07***85 | O-Ring,(Without Fuel Level Gauge) | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Torque Converter And Transmission : Transmission To Oil Cooler Piping
| 01***20 | Bolt,(For Quick Shift) (Mitsubishi) | 1 |
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 1 |
| 01***32 | Washer,(With Auto Emergency Steering) | 2 |
Work Equipment
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment : Bellcrank
| 01***20 | Bolt,(Without Rops Guard? Canopy) | 4 |
| 01***25 | Bolt,(For High High Lift) | 1 |
| 07***00 | Fitting, Grease - Upper Hinge Pin | 4 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment : Bolt-On Bucket Teeth (Esco)
| 02***70 | Bolt, Mount Center Adapters | 12 |
| 02***75 | Bolt, Mount Corner Adapters | 2 |
| 09***16 | Nut | 12 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment : Bolt-On Bucket Teeth (Komatsu)
| 01***60 | Flat Washer - M20 (Hardened) | 8 |
| 09***65 | Bolt, Plow (Bottom) | 14 |
| 09***16 | Nut | 14 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment : Bolt-On Cutting Edge
| 01***60 | Flat Washer - M20 (Hardened) | 8 |
| 02***70 | Bolt, Plow | 8 |
| 02***19 | Nut | 8 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment : Excavating Bucket 1.5 Cubic Yard / 1.2 Cubic Meter
| 41***20 | Blade, Cutting | 1 |
| 41***10 | Bucket, Excavating | 1 |
| 41***20 | Edge, Side Cutting | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment : General Purpose Bucket 1.75 Cubic Yard / 1.4 Cubic Meter
| 41***11 | Bucket, General Purpose | 1 |
| 41***30 | Edge, Side Cutting | 2 |
| 41***60 | Plate (Welded) | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment : Lift Arm
| 01***20 | Bolt,(Without Rops Guard? Canopy) | 8 |
| 07***00 | Fitting, Grease - Upper Hinge Pin | 6 |
| 07***75 | Fitting,Grease (Without Lub. Piping) | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment : Light Material Bucket 2.25 Cubic Yard / 1.7 Cubic Meter
| 41***20 | Blade, Cutting | 1 |
| 41***10 | Bucket, Light Material | 1 |
| 41***20 | Edge, Side Cutting | 2 |
Work Equipment Control System
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment Control System : 2-Spool Control Valve
| 01***12 | Bolt | 4 |
| 01***30 | Bolt | 4 |
| 07***38 | Ring, Seal - Between Sections | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment Control System : 3-Spool Control Valve
| 01***12 | Bolt | 6 |
| 01***25 | Bolt, Seal Cover Mounting | 2 |
| 01***30 | Bolt | 4 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment Control System : Boom Kick-Out And Bucket Positioner
| 01***20 | Bolt,(Used When Towing Winch) | 2 |
| 01***25 | Bolt - Rear Guard Mounting | 1 |
| 01***30 | Bolt,Radio Controlled Slag Handling | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment Control System : Dump Cylinder
| 04***25 | Ring,Snap (Kit) | 1 |
| 07***25 | O-Ring,Cylinder Head | 1 |
| 07***30 | Ring,Wear (Kit) | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment Control System : Front Attachment Control Lever And Linkage
| 01***70 | Bolt, Spacer | 2 |
| 01***06 | Nut? L.H. Thread,L.H. Thread (For Chinese) | 1 |
| 01***08 | Nut,R.H. Thread | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment Control System : Hydraulic Piping (Control Valve To Dump Cylinder)
| 01***35 | Bolt, Mounting - Flywheel Housing End | 1 |
| 01***50 | Bolt | 1 |
| 01***25 | Bolt - Rear Guard Mounting | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment Control System : Hydraulic Piping (Control Valve To Lift Cylinders)
| 01***55 | Bolt,(For Suction? Reversible Fan) | 2 |
| 01***30 | Bolt,Radio Controlled Slag Handling | 2 |
| 01***40 | Bolt,(Dust And Dirt Protection) | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment Control System : Hydraulic Piping (Front Attachment - Control Valve To Frame)
| 01***25 | Bolt,(Sandy? Dusty Terrain Spec.) | 4 |
| 01***50 | Bolt - Torque Converter Totransmission Mounting | 4 |
| 01***30 | Bolt,(Not Used With Emergency Str.) | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment Control System : Hydraulic Piping (Front Attachment - Frame To Lift Arms)
| 01***25 | Bolt - Rear Guard Mounting | 2 |
| 01***25 | Bolt,(Without Rops Guard? Canopy) | 2 |
| 01***35 | Bolt, Bolt, Mount Tubes To Switch And Work Pumps | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment Control System : Hydraulic Piping (Reservoir To Pump And Valves)
| 01***40 | Bolt,(For Position Fixing) | 4 |
| 01***25 | Bolt,(Sandy? Dusty Terrain Spec.) | 4 |
| 01***50 | Bolt | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment Control System : Hydraulic Piping (Valves To Reservoir)
| 01***16 | Bolt,(Sandy And Dusty Spec.) | 1 |
| 01***25 | Bolt - Rear Guard Mounting | 1 |
| 01***50 | Bolt - Torque Converter Totransmission Mounting | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment Control System : Hydraulic Pump (Barnes) Lift, Dump, And Steering
| 12***H1 | Plate, Wear | 2 |
| 14***91 | Pump Assembly, Hydraulic | 1 |
| 14***H1 | Kit, Seal | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment Control System : Hydraulic Pump (Komatsu) Lift, Dump, And Steering
| 01***32 | Washer, (Without Emergency Steering) | 4 |
| 04***24 | Pin,Dowel (For No.3 Housing) | 4 |
| 04***18 | Ring, Retaining | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment Control System : Hydraulic Reservoir
| 01***25 | Bolt,(Sandy? Dusty Terrain Spec.) | 6 |
| 01***30 | Bolt,Radio Controlled Slag Handling | 2 |
| 01***30 | Bolt,(Not Used With Emergency Str.) | 2 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment Control System : Lift Cylinder - Lh
| 07***15 | O-Ring,(Y1621-01a0-10) | 1 |
| 07***25 | Ring,Wear (For Wa120-1m) | 1 |
| 07***41 | Nut, Nylon | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment Control System : Lift Cylinder - Rh
| 07***15 | O-Ring,(Y1621-01a0-10) | 1 |
| 07***25 | Ring,Wear (For Wa120-1m) | 1 |
| 07***41 | Nut, Nylon | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment Control System : Priority Valve
| 41***01 | Priority Valve Assembly | 1 |
| 41***10 | Housing | 1 |
| 41***20 | Spool | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment Control System : Priority Valve (Eaton)
| 12***H1 | Spring | 1 |
| 12***H1 | O-Ring | 1 |
| 12***H1 | O-Ring | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment Control System : Relief Valve (2-Spool Or 3-Spool Control Valve)
| 01***05 | Nut,(For Air Conditioner Less), Nut | 1 |
| 07***12 | O-Ring (Itl) | 1 |
| 07***12 | Ring,Back-Up; Was 07001-02012, Ring,Back-Up (Itl) | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment Control System : Suction And Safety Valve (2-Spool Control Valve)
| 07***12 | O-Ring, Divider Valve Mounting | 1 |
| 07***12 | Ring,Back-Up; Was 07001-02012, Ring,Back-Up (Itl) | 1 |
| 07***34 | O-Ring, O-Ring, Oil Level And Fill Plug | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment Control System : Suction And Safety Valve (3-Spool Control Valve)
| 07***12 | O-Ring, Divider Valve Mounting | 1 |
| 07***12 | Ring,Back-Up; Was 07001-02012, Ring,Back-Up (Itl) | 1 |
| 07***34 | O-Ring, O-Ring, Oil Level And Fill Plug | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment Control System : Suction Valve (2-Spool Or 3-Spool Control Valve)
| 07***34 | O-Ring, O-Ring, Oil Level And Fill Plug | 1 |
| 70***50 | Spring | 1 |
| 70***10 | Sleeve | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment Control System : Work Equipment Control Lever
| 01***30 | Bolt,(For France Noise Suppression) | 3 |
| 01***20 | Bolt,(With Auto Emergency Steering) | 2 |
| 01***19 | Nut, Hex | 1 |
Komatsu : Wa120-1lc(S/N A20001-Up) : Work Equipment Control System : Work Equipment Control Linkage
| 01***70 | Bolt, Spacer | 2 |
| 01***20 | Bolt,(Without Maintenance Monitor) | 2 |
| 01***06 | Nut? L.H. Thread,L.H. Thread (For Chinese) | 2 |
WA120-1LC(S/N A20001-UP) serial number reference
The PIN plate is located on the front frame, on the right-hand side of the articulation joint. Read the prefix as the leading character(s) before the numeric serial sequence (e.g., 'A' in A20001).
| Prefix | Identifies | Notes |
|---|---|---|
| A | WA120-1LC | Serial range A20001-UP. Engine: S4D102E-1. Series: WA120-1 (Dash-1). Production years: 1987–1994. Configuration: Wheel loader. Note: The 'LC' suffix is not explicitly defined in the provided source text; data applies to the base WA120-1 model per factory spec sheet and parts catalog alignment. |
Frequently asked questions
What engine does the Komatsu WA120-1LC use?
The Komatsu WA120-1LC (S/N A20001-UP) is powered by the Komatsu S4D102E-1 diesel engine.
What is the operating weight of the WA120-1LC?
The operating weight is approximately 8 tons (8,818 lb), varying slightly by configuration and attachment package.
What model replaced the Komatsu WA120-1LC?
The WA120-1LC was succeeded by the Komatsu WA120-3 series, which introduced a four-speed transmission and updated emissions compliance.
What WA120-1LC(S/N A20001-UP) owners discuss
What engine does the WA120-1LC (S/N A20001-UP) use, and what are its power and displacement specs?
The WA120-1LC uses the Komatsu 6D95L engine. It has 4 cylinders, a displacement of 298.5 cu in (4.89 L), and produces 63 hp (47 kW) at 2400 rpm. Gross power is rated at 63 hp (47 kW). Note: WA120-1LC data is treated as applying to the WA120-1 base model per source grouping; WA120-3 specs may vary by configuration/series.
What are the typical hydraulic pump flow and transmission gear configurations for this machine?
The hydraulic pump flow capacity is 30.4 gal/min (115 L/min). The transmission has 3 forward gears and 3 reverse gears. Max speed is 21.5 mph (34.6 km/h) forward and 21.8 mph (35.1 km/h) reverse. These specs apply to the WA120-1LC per the provided WA120-1 data grouping; WA120-3 variants may differ.
What are the key undercarriage and tire specifications for the WA120-1LC?
The machine uses 16.9-24 tires. Operating weight is 16,953.6 lb (7,689 kg). Static tipping weight is 13,889.2 lb (6,300 kg). Rear axle oscillation is 24 degrees. Ground clearance is 1.28 ft (0.39 m). Bucket dump clearance at max raise is 8.83 ft (2.69 m). Bucket capacity is 1.57 cu yd (1.20 m³) struck and 1.84 cu yd (1.41 m³) heaped. Breakout force is 13,490 lbf (60.0 kN). Note: WA120-1LC data is treated as applying to the WA120-1 base model per source grouping; WA120-3 specs may vary by configuration/series.
What are the common maintenance intervals and fluid capacities for the WA120-1LC?
Fuel capacity is 35.2 gal (133 L). Engine oil changes are every 250 hours. Transmission oil changes are every 1,000 hours. Hydraulic oil changes are every 1,000 hours. Coolant replacement is every 2,000 hours. Air filter elements are checked every 50 hours and replaced as needed. Hydraulic tank breather element is replaced every 2,000 hours. Brake disc wear is checked every 2,000 hours. Valve lash clearance is adjusted every 1,000 hours and 2,000 hours. Fan belt tension is checked every 1,000 hours. Turbocharger play is checked every 1,000 hours. Water pump is checked every 4,000 hours. Note: WA120-1LC data is treated as applying to the WA120-1 base model per source grouping; WA120-3 specs may vary by configuration/series.
What are the common electrical and sensor issues reported for Komatsu WA120 series loaders?
Komatsu WA120 series loaders rely on electronic control systems. Common issues include intermittent starting, dashboard failure, and random shutdowns triggered by faulty sensors or unstable power supplies. Owners report that a single faulty sensor can cause multiple warning signals. Note: WA120-1LC data is treated as applying to the WA120-1 base model per source grouping; WA120-3 specs may vary by configuration/series.
What are the typical powertrain and hydraulic behaviors for the WA120-1LC?
The WA120-1LC is known for smooth operation and fuel efficiency. Hydraulic systems are generally reliable but can suffer from internal leakage when hot. If all hydraulic functions become slow, check hydraulic oil level, correct oil specification, hydraulic filters, engine RPM under load, and hydraulic oil temperature. If only one function is slow, check cylinder leakage, control valve spool operation, hose restriction, and pilot control input. Note: WA120-1LC data is treated as applying to the WA120-1 base model per source grouping; WA120-3 specs may vary by configuration/series.
What should be checked when buying a used WA120-1LC (S/N A20001-UP)?
Check the engine oil level and condition. Check the transmission oil level and condition. Check the hydraulic oil level and condition. Check the coolant level and condition. Check the fuel filter and water separator. Check the air filter element. Check the tire pressure and condition. Check the brake disc wear. Check the fan belt tension. Check the turbocharger play. Check the vibration damper. Check the alternator. Check the starter motor. Check the battery electrolyte level. Check the air conditioner compressor belt tension. Check the air conditioner condenser. Check the window washing fluid. Check the parking brake effect. Check the wheel brake effect. Check the horn and backup alarm. Check the flashing of lamps. Check the engine exhaust color and sound. Check the operation of gauges. Check the play of steering wheel. Check the direction of rear view mirror. Check the lock of cab door. Check the safety bar. Check the towing pin. Check the grease pump clamp and rubber ring. Check the slow blow fuse. Check the fuse capacity and name of circuit. Check the auxiliary power source. Check the location of decals referring to lifting positions. Check the weight list. Check the lifting procedure. Check the permissible water depth. Check the precautions when driving up or down slopes. Check the precautions when driving machine. Check the operation of work equipment. Check the boom operation. Check the bucket operation. Check the work possible using wheel loader. Check the digging operations with rock piles. Check the digging operations on level ground. Check the leveling operation. Check the pushing operations. Check the load and carry operations. Check the loading operations. Check the precautions for operation. Check the handling the tires. Check the precautions when handling the tires. Check the tire pressure. Check the transportation. Check the loading, unloading work. Check the precautions for loading. Check the precautions for lifting up the vehicle. Check the cold weather operations. Check the precautions for low temperature. Check the fuel and lubricants. Check the coolant. Check the battery. Check the precautions after completing work. Check the after cold weather. Check the long term storage. Check the before storage. Check the during storage. Check the after storage. Check the troubleshooting. Check the when machine runs out of fuel. Check the towing the machine. Check the when engine can be used. Check the when engine cannot be used. Check the if battery is discharged. Check the removal and installation of battery. Check the precautions for charging battery. Check the starting engine with booster cable. Check the other trouble. Check the electrical system. Check the chassis. Check the engine. Check the guides to maintenance. Check the outlines of service. Check the outline of oil, fuel, coolant. Check the oil. Check the fuel. Check the coolant. Check the grease. Check the storing oil and fuel. Check the filters. Check the outline of electric system. Check the wear parts list. Check the use of fuel, coolant and lubricants according to ambient temperature. Check the engine oil specifications. Check the diesel fuel specifications. Check the coolant specifications. Check the standard tightening torque for bolts and nuts. Check the introduction of necessary tools. Check the torque list. Check the periodic replacement of safety critical parts. Check the maintenance schedule chart. Check the initial 250 hours service. Check the replace fuel filters. Check the replace transmission oil filter element. Check the replace hydraulic tank filter element. Check the when required. Check the check, clean or replace air cleaner element. Check the check transmission oil level, add oil. Check the check axle oil level, add oil. Check the clean the axle case breather. Check the clean radiator fins. Check the replace the bolt-on cutting edges. Check the replace bucket teeth (if equipped). Check the check air conditioner (if equipped). Check the check the air conditioner condenser (if equipped). Check the check window washing fluid. Check the adjust parking brake. Check the replace slow blow fuse. Check the check air intake heater. Check the check before starting. Check the every 50 hours service. Check the check the tire inflation pressure. Check the drain water, sediment from fuel tank. Check the check engine air intake system. Check the every 100 hours service. Check the check oil level in hydraulic tank, add oil. Check the clean element in air conditioner fresh air filter. Check the lubricating. Check the every 250 hours service. Check the change oil in engine oil pan and replace engine oil filter. Check the check for loose wheel bolts. Tighten. Check the clean element in air conditioner recirculation filter. Check the check air conditioner compressor belt tension, adjust. Check the check battery electrolyte level. Check the check air intake system. Check the lubricating. Check the every 500 hours service. Check the replace fuel filters. Check the replace transmission oil filter element. Check the lubricate. Check the every 1000 hours service. Check the change oil in transmission case, clean strainer. Check the clean transmission case breather. Check the lubricate. Check the change oil in hydraulic oil tank, replace hydraulic filter element. Check the adjust engine valve lash clearance. Check the check fan belt tension. Check the check fan belt tensioner bearing & fan hub bearing & inspect fan belt. Check the check tightening parts of turbocharger. Check the check play of turbocharger rotor. Check the every 2000 hours service. Check the cooling system, replace coolant and flush the system. Check the replace hydraulic tank breather element. Check the check brake disc wear. Check the check alternator. Check the check starter motor. Check the check vibration damper. Check the replace element in air cond. recirculation air filter and fresh air filter. Check the adjust engine valve lash clearance. Check the clean and check turbocharger. Check the every 4000 hours service. Check the check water pump. Note: WA120-1LC data is treated as applying to the WA120-1 base model per source grouping; WA120-3 specs may vary by configuration/series.
Compiled from owner and technician discussions across the industry — experiences vary by serial range and machine history.
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