Komatsuwheel loadersmall ( - wa120 / sk*)
Komatsu WB98A-2(S/N WB98F20001-Up)
Maintenance schedule, common problems & OEM parts breakdown
The Komatsu WB98A-2 (S/N WB98F20001-Up) is a mid-size wheeled backhoe loader built for emerging-market job sites. Komatsu marketed it as a "3 machines in 1" package: front loader shovel, rear backhoe digging arm, and tool carrier on one chassis, with a telescopic dipper stick offered on some configurations. It runs a Komatsu S4D106-1FC 4-cylinder diesel, 4.41 L displacement, mechanically governed with no electronic engine controls or onboard diagnostics, rated around 72 kW (96.5 hp). Operating weight runs 8,290-8,750 kg (18,280-19,290 lb) with the backhoe fitted, or roughly 7,700-7,970 kg (16,975-17,570 lb) set up as a tool carrier with rear counterweight instead of the backhoe. This "-2" series covers 1999-2005 production, following the original WB98A (1997-1999) and sharing its chassis, engine family, and running gear with siblings WB90-2, WB93R-2, WB97R-2, and WB140-2.
The "-2" update over the base WB98A carried a common S4D106 engine and hydraulic layout across the whole WB90-2 through WB140-2 backhoe-loader range, so parts, filters, and service procedures largely interchange within the family. Komatsu moved this platform to a "-5" series generation from around 2005, and the WB93R/WB97R nameplates have carried forward through further generations since. In the used and parts market, the WB98A-2 stays relevant because its mechanically governed engine and simple hydraulics are cheaper to keep running and diagnose than later electronically controlled machines, and because its shared driveline with sibling WB models keeps used parts and rebuild kits in circulation for engines, axles, and pins and bushings.
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 WB98A-2(S/N WB98F20001-Up) specifications
Engine
| Engine model | Komatsu S4D106-1FC, 4-cylinder inline diesel, low-emissions rating |
| Displacement | 4.41 L (4,412 cc) |
| Rated power (SAE J1349) | 72 kW / 96.5 hp at 2,200 rpm |
| Rated power (DIN 6271) | 73.1 kW / 99.5 PS at 2,200 rpm |
| Max (gross) power | 84.2 kW / 112.9 hp |
| Max torque | 375 Nm at 1,500 rpm |
Weights
| Operating weight, with backhoe (ISO 6016) | 8,290 kg (18,276 lb) |
| Max weight, with backhoe and options | 8,750 kg (19,291 lb) |
| Operating weight, tool-carrier config with rear counterweight (ISO 6016) | 7,700 kg (16,976 lb) |
| Max weight, tool-carrier config with counterweight | 7,970 kg (17,571 lb) |
| Backhoe unit mass, with bucket | 2,100 kg (4,630 lb) |
Dimensions
| Transport length | 5,575 mm (18 ft 3 in) |
| Transport width, over standard loader bucket | 2,250 mm (7 ft 5 in) |
| Transport height, standard arm folded | 3,650 mm (12 ft 0 in) |
| Transport height, offset-boom version | 3,740 mm (12 ft 3 in) |
| Wheelbase | 2,355 mm (7 ft 9 in) |
| Ground clearance | 440 mm (17.3 in) |
| Cab height | 2,920 mm (9 ft 7 in) |
| Frame articulation angle | ±40°, central pivot |
| Frame oscillation, through bearing ring | ±10°, lockable from the cab |
Performance
| Backhoe dig depth, standard arm | 4.50 m (14 ft 9 in) |
| Backhoe dig depth, telescopic arm extended | 5.65 m (18 ft 6 in) |
| Backhoe dig depth (2 ft flat bottom), standard arm | 4.95 m (16 ft 3 in) |
| Backhoe dig depth (2 ft flat bottom), telescopic extended | 6.10 m (20 ft 0 in) |
| Backhoe reach from swivel, standard arm / offset boom | 5.55 m (18 ft 2 in) |
| Backhoe reach from swivel, telescopic extended | 6.55 m (21 ft 6 in) |
| Loader max dump clearance | 2.79 m (9 ft 2 in) |
| Loader lift capacity at max height (ISO 8313) | 3,223 kg (7,106 lb) |
| Loader lift capacity at ground level (ISO 8313) | 6,191 kg (13,649 lb) |
| Loader breakout force (ISO 8313) | 63.5 kN / 6,477 kgf (14,275 lbf) |
| Backhoe bucket breakout force (ISO 6015) | 58.1 kN / 5,926 kgf (13,065 lbf) |
| Backhoe arm (dipper) breakout force (ISO 6015) | 37.7 kN / 3,846 kgf (8,479 lbf) |
| Backhoe bucket rotation | 200° |
| Travel speed, 1st / 2nd range | 0-6.5 km/h (0-4.0 mph) / 0-12 km/h (0-7.5 mph) |
| Travel speed, 3rd / 4th (max) range | 0-20 km/h (0-12.4 mph) / 0-36 km/h (0-22.4 mph) |
| Hydraulic system flow / pressure | 165 L/min (43.6 US gpm) at 20 MPa / 200 bar (2,900 psi) |
Values vary by configuration, region, and serial range — confirm against your machine before planning transport or lifts.
WB98A-2(S/N WB98F20001-Up) fluids & capacities
| System | Capacity | Recommended fluid |
|---|---|---|
| Engine crankcase (with filter) | 9 L (2.4 US gal) | Komatsu Genuine EO engine oil. Use SAE 10W-30 across most seasonal ranges, SAE 15W-40 in warm/hot climates, and SAE 10W in sub-zero cold. Match grade to ambient temperature per the OMM viscosity chart. |
| Cooling system | 18 L (4.8 US gal) | Komatsu Super Coolant AF-NAC, a pre-mixed permanent-type antifreeze/coolant. Do not top off with a different coolant brand or plain water long-term. |
| Fuel tank | 110 L (29.1 US gal) | No. 2-D diesel fuel for normal operation. Switch to No. 1-D or a winter-grade blend in cold weather to prevent fuel waxing/gelling. |
| Power train (transmission) case | Not separately published for this serial range - confirm exact refill volume with the OMM or a dealer | Komatsu Genuine TO power train oil. SAE 10W in cold climates, SAE 30W in warm climates. |
| Front axle (differential and wheel-end reduction hubs) | 12 L (3.2 US gal) | Komatsu Genuine AXO axle (gear) oil, SAE 80W-90 class, GL-4/GL-5 rating. |
| Rear axle (differential and wheel-end reduction hubs) | 10 L (2.7 US gal) | Komatsu Genuine AXO axle (gear) oil, SAE 80W-90 class, GL-4/GL-5 rating. |
| Hydraulic system (tank and circuit, covers loader and backhoe boom/dipper/bucket/stabilizer/swing functions on one shared system) | 90 L (23.8 US gal) total system | Komatsu Genuine HO hydraulic oil, ISO VG46 grade. Use a lighter SAE 10W-equivalent grade in cold climates up to a heavier SAE 30-equivalent grade in hot climates per the ambient-temperature chart. The backhoe boom/dipper/stabilizer circuit is not broken out as a separate fill point; it draws from the same tank and system total. |
| Grease (all lubrication fittings, loader and backhoe pivots) | Spec only - no fixed refill volume, applied per grease point at scheduled intervals | Komatsu Genuine G2-LI multi-purpose lithium-base grease, NLGI 2. |
Capacities are refill values from factory literature — always fill to the dipstick/sight gauge, not the number.
Komatsu WB98A-2(S/N WB98F20001-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 WB98A-2(S/N WB98F20001-Up) beyond the schedule
Predictive Maintenance & Fluid Analysis
The S4D106-1FC is mechanically governed, so there is no ECM fault log to lean on. Pull engine oil, power train oil, and front/rear axle differential and final-drive oil samples at the 250 h through 1000 h checkpoints for lab analysis; metal in axle oil catches final-drive gear wear before it reaches the housing. Watch hydraulic oil condition too, since one system powers the loader, backhoe, and any tool-carrier attachment. Drain fuel tank sediment regularly; water in fuel is the most common no-start complaint on this engine.
Corrective & Common Repairs
Most repair calls on this platform trace to backhoe and loader linkage pins and bushings wearing loose from constant loader-backhoe-tool-carrier duty cycles; regreasing on schedule slows this but pins eventually need replacing. Power-train charge-pressure loss shows up as sluggish travel or weak breakout force. Check starter, alternator, and battery cable connections at each 250 h service; corrosion here causes hard-starting complaints on this mechanically governed engine. Clogged radiator fins from mixed road-and-site dust cause overheating; clean at every 500 h interval.
Overhaul & Rebuild Points
Engine overhaul on the S4D106 centers on cylinder liners, piston rings, and main/rod bearings; rebuild kits are cataloged specifically for the engine fitted to this WB98A-2/WB93R-2 platform. Axle kingpins, oscillation pins, and center-pivot bushings take heavy load from mixed on-road travel and digging, and are common rebuild points on high-hour machines. Loader and backhoe boom, dipper, and bucket pin-bushing sets open up with use; re-bush as a set to keep linkage geometry tight, not one pin at a time.
Seasonal & Environment Servicing
Check coolant glycol protection before cold-weather work; this mechanically governed engine has no electronic block-heater management, so cold starts rely on healthy batteries and the glow-plug preheat system. In hot, dusty sites, clean the radiator and A/C condenser more often than the standard 500 h interval and check tire pressure weekly, since this machine road-travels between sites at up to 36 km/h (22.4 mph). In wet climates, drain the fuel tank sump and check the brake reservoir often; moisture ingress is a common cold-season failure on this platform.
WB98A-2(S/N WB98F20001-Up) common service parts
| Part number | Part | Notes | |
|---|---|---|---|
| YM129470-55610 | Body, Fuel Filter | Fuel system service | Check fitment → |
| YM120324-55760 | Element, Fuel Oil | Fuel system service | Check fitment → |
| 885141118 | Glass, Air Filter Clogging | Air intake service | Check fitment → |
| 885141126 | Glass, Transmission Oil Filter Clogging | Lubrication service | Check fitment → |
| YM119000-55600 | Filter Element | Scheduled service item | Check fitment → |
Always confirm against your machine's serial number — cross-check any part in Heavy Parts AI before ordering.
WB98A-2(S/N WB98F20001-Up) fault codes & troubleshooting
| Code | Meaning | Likely cause | What to do |
|---|---|---|---|
| Engine oil pressure warning lamp (oil can symbol) | Engine lubrication pressure has dropped below the safe minimum. | Low oil level, a failed oil pressure switch, a worn oil pump, or a clogged oil filter. | Stop the engine immediately, check oil level and top off, look for leaks, replace the filter, and confirm the pressure switch operates correctly before restarting. |
| Engine coolant temperature warning lamp | Coolant temperature has gone above the normal operating range. | Low coolant level, a clogged radiator core, a slipping or broken fan belt, or a thermostat stuck closed. | Let the engine idle to cool, shut down safely, check coolant level and belt tension, clean the radiator core, and inspect the thermostat. |
| Charge (alternator) warning lamp | Alternator is not charging the battery; the lamp stays lit at running speed instead of going out. | A worn or broken fan/alternator belt, a failed alternator, or loose or corroded battery connections. | Check belt tension and condition, test alternator output, and inspect battery terminals and charging wiring. |
| Glow plug preheat indicator lamp | Shows the cold-start preheat cycle is running; a lamp that stays on too long or flashes points to a fault in the preheat circuit. | A faulty glow plug, an open preheat relay or timer circuit, or a blown fuse in the preheat circuit. | Let the normal preheat cycle finish before cranking; if the lamp stays on or cold starts are hard, test the glow plugs and preheat relay. |
| Air cleaner (intake filter) restriction lamp | Intake air filter element is clogged, restricting airflow to the engine. | A dust-loaded primary air filter element or a blocked pre-cleaner/dust valve. | Stop and inspect the air filter housing, clean or replace the element, and check the dust valve. |
| Hydraulic oil filter clogging lamp | Return-line hydraulic filter is loading up and restricting flow. | A filter element at the end of service life, contaminated hydraulic oil, or cold, high-viscosity oil briefly tripping the bypass switch on startup. | Warm the machine and recheck; if the lamp stays lit, replace the hydraulic filter element and check oil condition. |
| Parking brake warning lamp | Parking brake is applied, or brake circuit pressure/fluid is low. | Brake left engaged, low brake fluid, or a fault in the parking brake switch or wiring. | Confirm parking brake lever position, check brake fluid level, and inspect the brake switch and wiring if the lamp stays lit with the brake released. |
| Transmission oil temperature warning lamp | Torque converter/transmission oil temperature has gone above the normal range. | Low transmission oil level, a clogged transmission oil cooler, or sustained high-load or stall operation such as digging against a full bucket. | Reduce load and let the transmission cool, check oil level, and inspect the cooler for restriction or clogged fins. |
Codes and remedies are general guidance for this model family — always confirm with diagnostic tooling and your dealer before major repairs.
WB98A-2(S/N WB98F20001-Up) attachments & work tools
Front loader buckets
Standard general-purpose loader bucket rated around 1.0-1.4 m³ (1.3-1.8 yd³, varies by configuration/series) with an operating width near 2.25 m (88.6 in) and breakout force around 6,475 kg (14,275 lb). A folding/multi-purpose bucket was also fitted to some units for combined dozing, grading, and light clamping work.
Rear backhoe digging bucket
Standard trenching/digging bucket on the backhoe arm gives a standard dig depth of roughly 4.5-4.95 m (14.8-16.2 ft) with dig force around 5,900-5,950 kg (13,000-13,100 lb). Narrower buckets for utility-trench work are common across this size class, but exact WB98A-2 width options are not spelled out in available factory spec sheets - confirm with your dealer.
Extendable (telescopic) dipperstick
An extendable backhoe dipperstick option pushes dig depth out to about 5.5-5.7 m (18.3-18.6 ft) and increases horizontal reach from the swing pivot to roughly 6.5 m (21.5 ft), versus the shorter standard-arm figures. Factory spec sheets and used-unit listings for this exact model both show the telescopic arm as an available configuration rather than a separate model.
Pallet forks and flip-over forks
Pallet forks and combination flip-over fork/bucket attachments mount on the front loader linkage for material handling and pipe/pallet work. Used-market listings for this model confirm units delivered or later fitted with forks alongside the standard front bucket.
Quick coupler / quick hitch (front and rear)
A pin-less quick coupler on the loader arm and a matching quick hitch on the backhoe dipper let the operator swap buckets, forks, and other tools without leaving the cab. This backhoe-loader family lists the coupler as a factory or dealer-fit option, and used WB98A-2 units are regularly found equipped with a quick hitch.
Hydraulic breaker (hammer)
A hydraulic breaker can be run off the backhoe's auxiliary hydraulic circuit through the quick coupler for demolition, trenching in rock, and pavement removal. Breaker sizing should match this machine's operating weight class of roughly 8-8.75 t; confirm auxiliary flow and pressure compatibility with your dealer before fitting.
Earth auger
A hydraulically driven earth auger mounts on the backhoe dipper via the quick coupler for post-hole, fence-post, and foundation drilling. Drive-unit torque and bit sizing are matched to the machine's auxiliary hydraulic circuit rather than being unique to this serial range.
Steering mode selection
Backhoe loaders in this class offer selectable two-wheel, four-wheel, and crab steering modes from a dash-mounted switch, aiding maneuverability on confined sites and reducing tire scrub when working sideways. Availability of all three modes specifically on the WB98F20001-Up serial range is not separately documented in available literature - verify with your dealer.
Backhoe stabilizers and boom sideshift
Fixed outrigger stabilizer legs at the rear are standard equipment, extended before digging to steady the machine and take load off the tires. Some units in this family also offer a hydraulically sideshiftable backhoe swing frame for digging tight against walls or in narrow trenches; confirm whether this specific serial range includes sideshift with your dealer.
All WB98A-2(S/N WB98F20001-Up) assemblies by section
Every catalogued assembly group for the Komatsu WB98A-2(S/N WB98F20001-Up). Open an assembly to preview the parts inside — full OEM part numbers are available in Heavy Parts AI.
Control System
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Control System : Backhoe Control Levers
| 20***98 | Pin | 1 |
| 20***50 | Lever, R.H | 2 |
| 20***35 | Locking | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Control System : Backhoe Control Pedal (For Side Digging Boom)
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Control System : Backhoe Control Pedal (For Telescopic Arm)
| 39***81 | Tie-Rod | 1 |
| 50***07 | Spacer | 1 |
| 50***25 | Spacer | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Control System : Braking Control Pedal
| 20***01 | Pin | 1 |
| 20***20 | Clamp | 1 |
| 35***52 | Pushrod | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Control System : Bucket - 4 In 1 Control Lever
| 36***93 | Catch | 1 |
| 36***57 | Handle | 1 |
| 36***05 | Tie-Rod | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Control System : Fuel Control Lever
| 31***81 | Support | 1 |
| 31***10 | Dowel | 1 |
| 36***74 | Cable | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Control System : Inching Control Pedal
| 36***07 | Plate | 1 |
| 39***65 | Tie-Rod | 1 |
| 39***17 | Hose | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Control System : Shovel Control Lever
| 31***51 | Lever | 1 |
| 35***52 | Knob | 1 |
| 36***59 | Support | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Control System : Steering Wheel, Column And Unit
| 20***83 | Steering Coloumn, Assembly | 1 |
| 31***04 | Pin | 1 |
| 36***65 | Support | 1 |
Engine
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine : Air Intake Manifold
| YM***00 | Heather Air | 1 |
| YM***02 | Screw | 9 |
| YM***41 | Pipe | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine : Camshaft And Driving Gear
| YM***20 | Gear Assembly., Hydraulic Pump | 1 |
| YM***00 | O-Ring | 1 |
| YM***50 | Bearing, Thrust | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine : Cooling Water System
| YM***10 | Protector | 1 |
| YM***02 | Screw | 6 |
| YM***40 | Fan | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine : Crankshaft And Piston
| YM***00 | Connecting Rod, Assembly | 4 |
| YM***00 | Assembly, Piston (+0.25 mm) | 4 |
| YM***80 | Gear, Ring | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine : Cylinder Block
| YM***00 | Screw | 18 |
| YM***20 | Screw | 10 |
| YM***40 | Bearing, Thrust (+0.25 mm) | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine : Cylinder Head
| 87***31 | Engine, Assembly | 1 |
| YM***70 | Cap Valve | 8 |
| YM***02 | Bolt | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine : Engine Stop Device
| YM***00 | Pin, Cotter | 2 |
| YM***02 | Nut | 1 |
| YM***20 | Joint | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine : Exhaust Manifold
| YM***80 | Packing | 1 |
| YM***20 | Stud | 4 |
| YM***00 | Stud Bolt | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine : Feed Pump
| YM***40 | Gasket | 4 |
| YM***60 | O-Ring | 2 |
| YM***00 | Screw | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine : Flywheel - Lubricating Oil Sump
| YM***02 | Screw | 22 |
| YM***20 | Oil Sump | 1 |
| YM***80 | Parallel Pin | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine : Fuel Injection Line
| YM***40 | Injection Pipe N. 4 | 1 |
| YM***02 | Bolt Plated | 1 |
| YM***20 | Spring | 4 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine : Fuel Injection Pump
| YM***11 | Pump, Assembly | 1 |
| YM***00 | Segment | 4 |
| YM***40 | Gasket | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine : Fuel Piping
| YM***02 | Screw | 1 |
| YM***80 | Screw | 1 |
| YM***50 | Pipe, Assembly | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine : Gasket Set
| YM***80 | Packing | 1 |
| YM***10 | O-Ring | 1 |
| YM***00 | O-Ring (Kit) | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine : Gear Housing
| YM***02 | Bolt Plated | 7 |
| YM***10 | O-Ring | 1 |
| YM***51 | Cap, Lub. Oil Supply | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine : Generator
| YM***40 | Distance Piece | 1 |
| YM***40 | Distance Piece | 1 |
| YM***30 | Adjuster, Belt | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine : Governor
| YM***00 | Gasket | 1 |
| YM***40 | Screw | 5 |
| YM***00 | Screw | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine : Lubricating Oil System (1/2)
| YM***00 | O-Ring (Kit) | 1 |
| YM***30 | Shim, 1.000 mm | 1 |
| YM***00 | Plug | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine : Lubricating Oil System (2/2)
| YM***81 | Retainer | 1 |
| YM***50 | Oil Pressure Transmitter | 1 |
| YM***00 | Retainer | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine : Starter Motor
| YM***20 | Shift Lever Ass'Y | 1 |
| YM***10 | Housing | 1 |
| YM***60 | Cover, Rear | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine : Turbocharger
| YM***02 | Nut | 4 |
| YM***90 | Packing | 1 |
| YM***10 | Turbine | 1 |
Engine Related Parts And Electrical System
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine Related Parts And Electrical System : Air Filter
| 36***64 | Cap (Optional) | 1 |
| 36***93 | Support | 1 |
| 36***17 | Sleeve | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine Related Parts And Electrical System : Battery
| 50***68 | Bracket | 2 |
| 50***07 | Rubber | 1 |
| 80***08 | Bolt (Only With Cabin) | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine Related Parts And Electrical System : Electrical System (1/3)
| 36***95 | Support | 1 |
| 36***63 | Wiring Harness, Rear | 1 |
| 36***65 | Wiring Harness | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine Related Parts And Electrical System : Electrical System (2/3)
| 31***00 | Acustic Alarm | 1 |
| 80***66 | Bolt | 2 |
| 80***08 | Bolt (Only With Cabin) | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine Related Parts And Electrical System : Electrical System (3/3)
| 36***84 | Support, L.H | 1 |
| 36***85 | Support, R.H | 1 |
| 36***05 | Protection | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine Related Parts And Electrical System : Engine Mounting Parts
| 36***87 | Conveyor | 1 |
| 36***86 | Support, Rear | 2 |
| 36***87 | Support Front | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine Related Parts And Electrical System : Front Dashboard (1/2)
| 36***97 | Front Instrument Board (Tbg Version) | 1 |
| 36***51 | Front Instrument Board | 1 |
| 80***42 | Screw | 5 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine Related Parts And Electrical System : Front Dashboard (2/2)
| 88***15 | Relay (Only For Tuv 20 Km/H) | 1 |
| 88***21 | Box | 1 |
| 88***25 | Relay | 11 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine Related Parts And Electrical System : Fuel Piping
| 36***63 | Support | 1 |
| 36***27 | Elbow | 1 |
| 36***09 | Level Indicator | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine Related Parts And Electrical System : Fuel Tank
| 20***57 | Plug, Assembly | 1 |
| 36***51 | Fuel Tank | 1 |
| 36***08 | Cover | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine Related Parts And Electrical System : Lateral Dashboard
| 36***61 | Front Instrument Board | 1 |
| 80***42 | Screw | 6 |
| 80***05 | Spring Washer | 6 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine Related Parts And Electrical System : Muffler
| 36***54 | Pipe | 1 |
| 36***88 | Support | 1 |
| 36***91 | Pipe | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine Related Parts And Electrical System : Power Take Off
| 36***55 | Cover | 1 |
| 80***08 | Bolt (Only With Cabin) | 2 |
| 80***09 | Screw | 10 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Engine Related Parts And Electrical System : Radiator
| 36***68 | Tank | 1 |
| 36***89 | Radiator, Assembly | 1 |
| 36***90 | Protection | 1 |
Frame
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Counter Weight
| 20***32 | Pin | 2 |
| 20***02 | Pin | 1 |
| 20***28 | Connecting Rod | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Frame
| 36***51 | Frame, Front | 1 |
| 36***53 | Cover | 1 |
| 36***60 | Frame, Rear | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Frame Articulation
| 36***55 | Support | 1 |
| 36***56 | Lock Plate | 1 |
| 36***57 | Joint | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Front Axle (1/9)
| 80***67 | Bolt (Optional) | 8 |
| 80***74 | Bolt | 4 |
| 80***96 | Bolt | 4 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Front Axle (2/9)
| 80***67 | Bolt (Optional) | 1 |
| 80***26 | Screw | 1 |
| 80***06 | Self-Lockig Nut | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Front Axle (3/9)
| 80***67 | Bolt (Optional) | 1 |
| 80***69 | Bolt (With Stabilizers Only) | 1 |
| 80***08 | Nut | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Front Axle (4/9)
| 36***10 | Support | 1 |
| 80***66 | Bolt | 1 |
| 80***67 | Bolt | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Front Axle (5/9)
| CA***99 | Casing | 1 |
| CA***22 | Screw | 4 |
| CA***88 | Breather | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Front Axle (6/9)
| 80***97 | Bearing | 2 |
| CA***70 | Shim, 3.000 mm | 0 |
| CA***68 | Shim, 2.800 mm | 0 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Front Axle (7/9)
| 50***53 | Plug | 8 |
| 85***17 | Gasket | 2 |
| CA***90 | Centering Bush | 16 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Front Axle (8/9)
| CA***80 | Oil Plug | 2 |
| CA***97 | Bearing Needles | 0 |
| CA***14 | Gear | 6 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Front Axle (9/9)
| CA***98 | Kit, Differential Gear | 1 |
| CA***78 | Locking Plate | 2 |
| CA***30 | Trusth Washer | 4 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Handbrake Control Lever
| 36***21 | Control Cable | 1 |
| 36***49 | Lockplate | 1 |
| 36***50 | Extension | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Hydraulic Piping (Brake Line)
| 20***10 | Clamp | 6 |
| 20***40 | Clamp | 2 |
| 36***58 | Pipe, R.H | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Hydraulic Piping (Frame Oscillation Locking)
| 36***50 | Piston, Assembly | 1 |
| 36***00 | Cylinder | 1 |
| 36***01 | Piston Rod | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Hydraulic Piping (Rear Axle Locking Control)
| 36***69 | Support | 1 |
| 36***47 | Union | 1 |
| 39***19 | Hose | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Hydraulic Piping (Reduction Gear Control)
| 36***02 | Union | 2 |
| 36***36 | Union | 1 |
| 39***15 | Hose | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Propeller Shaft And Travel Motor
| 36***50 | Cover | 1 |
| 36***56 | Propeller Shaft | 1 |
| 50***81 | Collar | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Rear Axle (1/6)
| 20***32 | Rear Axle, Assembly | 1 |
| CA***99 | Casing | 1 |
| CA***22 | Screw | 4 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Rear Axle (2/6)
| 80***44 | Bolt | 6 |
| 80***46 | Bolt | 2 |
| 80***10 | Nut | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Rear Axle (3/6)
| 50***53 | Plug | 8 |
| 85***17 | Gasket | 2 |
| CA***90 | Centering Bush | 16 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Rear Axle (4/6)
| CA***80 | Oil Plug | 2 |
| CA***97 | Bearing Needles | 0 |
| CA***14 | Gear | 6 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Rear Axle (5/6)
| CA***78 | Locking Plate | 2 |
| CA***30 | Trusth Washer | 4 |
| CA***52 | Bolt | 12 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Rear Axle (6/6)
| 85***13 | O-Ring | 1 |
| CA***36 | Fork | 1 |
| CA***41 | Support | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Rear Door
| 31***00 | Gasket | 1 |
| 36***65 | Platform | 1 |
| 36***73 | Mat | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Steering Cylinder
| 20***42 | Steering Cylinder | 2 |
| 20***30 | Cylinder | 1 |
| 20***05 | Piston Rod | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Frame : Wheels
| 11***59 | Idler, Assembly | 4 |
| 36***61 | Rim | 1 |
| 81***09 | Tyre (16/70x24 10pr) | 1 |
Guard And Operator'S Cab
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Guard And Operator'S Cab : Cabin (1/6)
| 36***82 | Canopy | 1 |
| 80***24 | Bolt | 2 |
| 80***36 | Bolt | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Guard And Operator'S Cab : Cabin (2/6)
| 80***69 | Screw | 1 |
| 80***73 | Bolt (Only For Canopy) | 1 |
| 80***49 | Screw | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Guard And Operator'S Cab : Cabin (3/6)
| 31***85 | Handle, External, R.H | 1 |
| 31***86 | Handle, External | 1 |
| 80***46 | Bolt | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Guard And Operator'S Cab : Cabin (4/6)
| 80***46 | Bolt | 4 |
| 80***79 | Bolt | 2 |
| 80***59 | Screw | 4 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Guard And Operator'S Cab : Cabin (5/6)
| 80***44 | Bolt | 6 |
| 80***68 | Bolt (Version A) | 2 |
| 80***68 | Screw | 27 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Guard And Operator'S Cab : Cabin (6/6)
| 80***01 | Screw (For Hydraulic Lock) | 4 |
| 80***73 | Bolt (Only For Canopy) | 2 |
| 80***12 | Washer | 4 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Guard And Operator'S Cab : Covers And Dashboards
| 31***15 | Plug | 1 |
| 36***01 | Cover | 1 |
| 36***34 | Dashboard | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Guard And Operator'S Cab : Floor Frame And Dashboard
| 36***51 | Platform | 1 |
| 36***52 | Rear Platform | 1 |
| 36***54 | Support | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Guard And Operator'S Cab : Heating System
| 31***53 | Support, Heating | 1 |
| 39***60 | Union | 1 |
| 39***34 | Union | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Guard And Operator'S Cab : Heating System Accelerator Pump
| 80***86 | Washer | 1 |
| 80***08 | Nut (With Stabilizers Only) | 1 |
| 80***01 | Spring Washer (With Stabilizers Only) | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Guard And Operator'S Cab : Operator'S Seat
| 31***14 | Operator'S Seat Stand | 1 |
| 36***76 | Operator'S Seat, Assembly | 1 |
| 80***35 | Bolt | 4 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Guard And Operator'S Cab : Operator'S Seat Support And Mats
| 36***06 | Mat | 1 |
| 36***68 | Mat | 1 |
| 36***70 | Mat | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Guard And Operator'S Cab : Sound-Proofing
| 36***06 | Panel, R.H | 1 |
| 36***07 | Panel, L.H | 1 |
| 36***08 | Panel, R.H | 1 |
Mark Plate
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Mark Plate : Equipment (For Road Circulation)
| 36***52 | Protection, Tooth | 1 |
| 50***73 | Connecting Rod | 1 |
| 50***99 | Spring | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Mark Plate : Equipment (Germany Version) (1/4)
| 36***54 | Support | 1 |
| 36***55 | Bushing | 1 |
| 80***86 | Washer | 8 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Mark Plate : Equipment (Germany Version) (2/4)
| 36***51 | Arm | 1 |
| 80***01 | Screw (For Hydraulic Lock) | 2 |
| 80***73 | Bolt (Only For Canopy) | 4 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Mark Plate : Equipment (Germany Version) (3/4)
| 36***51 | Support | 1 |
| 36***54 | Plate, Support | 1 |
| 36***19 | Plate | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Mark Plate : Equipment (Germany Version) (4/4)
| 36***00 | Front Mudguard, R.H | 1 |
| 36***01 | Front Mudguard, L.H | 1 |
| 36***02 | Rear Mudguard | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Mark Plate : Mark Plate
| 30***29 | Plate, Counterweight | 1 |
| 31***01 | Plate, Locking Bracket | 1 |
| 31***04 | Plate, Operating Backhoe | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Mark Plate : Tools
| 80***10 | Wrench | 1 |
| 82***35 | Grease Pump | 1 |
| 82***43 | Filter Cartridge Wrench | 1 |
Work Equipment
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Arm And Bucket
| 20***02 | Lever, R.H | 1 |
| 20***03 | Lever, L.H | 1 |
| 20***78 | Pin | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Arm Cylinder
| 39***01 | Piston Rod | 1 |
| 39***01 | Head, Cylinder | 1 |
| 39***01 | Piston | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Arm Cylinder (For Side Digging Boom)
| 39***11 | Bushing | 1 |
| 39***03 | Cylinder, Assembly | 1 |
| 39***12 | Cylinder | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Backhoe Frame And Outrigger (1/2)
| 20***24 | Chain (With Stabilizers Only) | 2 |
| 20***13 | Foot (Optional) | 2 |
| 20***14 | Foot, R.H | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Backhoe Frame And Outrigger (2/2)
| 20***32 | Pin | 2 |
| 20***56 | Pin | 1 |
| 31***50 | Support | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Blade
| 20***60 | Support, Angledozer | 1 |
| 20***31 | Blade, Dozer | 1 |
| 36***51 | Connection | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Blade Under Teeth - Blade Instead Of Teeth
| 36***51 | Blade | 1 |
| 36***51 | Blade | 2 |
| 80***99 | Bolt | 6 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Boom Cylinder
| 31***03 | Pipe Stopper | 1 |
| 39***07 | Plug | 1 |
| 39***01 | Piston | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Boom Cylinder (For Side Digging)
| 20***40 | Side Digging Boom Cylinder, Assembly | 1 |
| 20***20 | Cylinder | 1 |
| 20***80 | Piston Rod | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Bracket And Boom
| 20***66 | Slide Block | 2 |
| 20***94 | Support | 1 |
| 31***51 | Bracket | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Bucket - 4 In 1
| 31***54 | Tooth | 8 |
| 31***75 | Blade | 1 |
| 31***76 | Protection | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Bucket 4 In 1 Cylinder
| 31***03 | Piston Rod | 1 |
| 31***04 | Cylinder | 1 |
| 31***74 | Bucket 4 In 1 Cylinder, Assembly | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Bucket Cylinder
| 20***03 | Piston Rod | 1 |
| 39***04 | Bucket Cylinder, Assembly | 1 |
| 39***11 | Cylinder | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Bucket Tipping Cylinder
| 20***04 | Piston Rod | 1 |
| 39***18 | Cylinder, Assembly | 1 |
| 39***11 | Cylinder | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Fork
| 20***59 | Tooth | 2 |
| 36***51 | Frame | 1 |
| 82***47 | Fork, Assembly | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Hammer M50 (1/2)
| 82***33 | Chisel Point (Optional) | 1 |
| 82***38 | Flat Point (Optional) | 1 |
| 82***39 | Pyramid Point (Optional) | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Hammer M50 (2/2)
| 82***54 | Fitting | 1 |
| 82***55 | Retainer | 2 |
| 82***56 | Pin | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Hammer M60 (1/2)
| 82***34 | Chisel Point (Optional) | 1 |
| 82***45 | Flat Point (Optional) | 1 |
| 82***46 | Pyramid Point (Optional) | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Hammer M60 (2/2)
| 82***54 | Fitting | 2 |
| 82***58 | Spring | 2 |
| 82***61 | Adjuster Shim | 10 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Hydraulic Fast Coupling
| 36***53 | Tie-Rod | 1 |
| 36***54 | Pin | 2 |
| 36***57 | Frame | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Hydraulic Fast Coupling Cylinder
| 20***45 | Cylinder | 1 |
| 20***14 | Piston Rod | 2 |
| 50***20 | Cylinder Head | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : L.H. Boom Swing Cylinder
| 31***01 | Brake | 1 |
| 39***00 | Boom Swing Cylinder, Assembly., L.H | 1 |
| 39***01 | L.H. Cylinder | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Manual Fast Coupling
| 36***33 | Spacer | 1 |
| 36***53 | Tie-Rod | 1 |
| 36***52 | Pin | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Outrigger Cylinder
| 20***01 | Rod Piston | 1 |
| 39***05 | Vertical Outrigger Cylinder, Assembly | 2 |
| 39***11 | Cylinder | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : R.H. Boom Swing Cylinder
| 31***01 | Brake | 1 |
| 39***00 | Boom Swing Cylinder, Assembly., R.H | 1 |
| 39***01 | R.H. Cylinder | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Shovel Bucket And Arm
| 31***54 | Tooth | 8 |
| 33***53 | V-Belt | 1 |
| 36***50 | Arm | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Shovel Lifting Cylinder
| 20***48 | Cylinder, Assembly | 2 |
| 20***36 | Cylinder | 1 |
| 20***06 | Piston Rod | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Side Digging Boom
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Telescopic Arm
| 31***65 | Movable Arm (Casting Version) | 1 |
| 31***71 | Fixed Arm | 1 |
| 31***00 | Pin | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment : Telescopic Arm Cylinder
| 20***08 | Piston Rod | 1 |
| 39***12 | Cylinder Head | 1 |
| 39***16 | Piston | 1 |
Work Equipment Control System
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Backhoe Control Valve (1/4)
| 84***42 | Control Valve, Assembly | 1 |
| 84***72 | Washer | 2 |
| 84***75 | Cap, Assembly | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Backhoe Control Valve (2/4)
| 80***77 | Screw | 2 |
| 84***76 | Gasket | 1 |
| 84***41 | Element, Assembly | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Backhoe Control Valve (3/4)
| 80***77 | Screw | 4 |
| 84***76 | Gasket | 2 |
| 84***42 | Spool Return Unit | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Backhoe Control Valve (4/4)
| 80***77 | Screw | 4 |
| 84***76 | Gasket | 2 |
| 84***42 | Spool Return Unit | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Backhoe Control Valve (For Deportable)
| 80***77 | Screw | 2 |
| 84***54 | Control Valve, Assembly | 1 |
| 84***76 | Gasket | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Backhoe Control Valve (For Telescopic)
| 80***77 | Screw | 2 |
| 84***44 | Control Valve, Assembly | 1 |
| 84***76 | Gasket | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Arm And Bucket Cylinder Line)(For Side Digging Boom)
| 31***57 | Pipe | 1 |
| 31***58 | Pipe | 1 |
| 31***59 | Pipe, R.H | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Arm Cylinder Line)
| 31***53 | Support | 1 |
| 31***04 | Plate | 1 |
| 31***56 | Hose-Clamp | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Arm Cylinder Line) (Safety Valve)
| 31***01 | Support | 1 |
| 31***16 | Union | 1 |
| 31***50 | Pipe | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Boom Cylinder Line)
| 31***01 | Plate | 4 |
| 31***03 | Support | 1 |
| 31***13 | Clamp (Wit Hammer) | 6 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Boom Cylinder Line) (Safety Valve)
| 31***00 | Support | 1 |
| 31***51 | Pipe | 1 |
| 31***52 | Pipe | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Boom Swing Line)
| 31***01 | Plate | 4 |
| 31***03 | Support | 1 |
| 31***02 | Clamp (Without Hammer) | 6 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Bucket - 4 In 1 Cylinder Line)
| 20***51 | Coupling, Assembly. (For Hand Hammer) | 2 |
| 20***52 | Fitting (For Hand Hammer) | 1 |
| 20***53 | Body (For Hand Hammer) | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Bucket Cylinder Line) (1/2)
| 31***01 | Clamp | 1 |
| 31***02 | Bracket | 1 |
| 39***30 | Hose | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Bucket Cylinder Line) (2/2)
| 31***63 | Pipe | 1 |
| 31***01 | Retainer | 1 |
| 50***23 | Pin | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Bucket Cylinder Line) (For Telescopic Arm)
| 31***12 | Block | 1 |
| 31***63 | Pipe | 1 |
| 31***64 | Pipe | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Bucket Lifting Cylinder)
| 36***23 | Washer | 2 |
| 36***68 | Pipe | 2 |
| 36***12 | Protection | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Bucket Tipping Cylinder)
| 36***16 | Clamp | 1 |
| 36***52 | Pipe | 1 |
| 36***53 | Pin | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Delivery And Return Line)
| 20***54 | Coupling, Assembly | 1 |
| 20***55 | Fitting | 1 |
| 20***56 | Body | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Delivery And Return Line) (Backhoe Side)
| 20***54 | Coupling, Assembly | 1 |
| 20***55 | Fitting | 1 |
| 20***56 | Body | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Fast Coupling Line)
| 20***51 | Coupling, Assembly. (For Hand Hammer) | 4 |
| 20***52 | Fitting (For Hand Hammer) | 1 |
| 20***53 | Body (For Hand Hammer) | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Locker Cylinder Line)
| 20***72 | Locking Cylinder, Assembly | 4 |
| 31***00 | Slide Block | 4 |
| 31***58 | Pipe | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Oil Cooler And Return Line)
| 36***34 | Union | 2 |
| 39***08 | Hose | 1 |
| 39***06 | Hose | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Shovel Lifting Cylinder) (Safety Valve)
| 36***63 | Support | 2 |
| 36***66 | Pipe | 2 |
| 36***67 | Pipe | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Shovel Tipping Cylinder) (Safety Valve)
| 36***59 | Support | 1 |
| 36***00 | Clamp | 1 |
| 36***64 | Pipe | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Side Digging Boom Cylinder Line) (1/2)
| 39***34 | Hose | 1 |
| 39***35 | Hose | 1 |
| 50***23 | Union | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Side Digging Boom Cylinder Line) (2/2)
| 20***80 | Pin | 2 |
| 31***55 | Union | 1 |
| 31***56 | Union | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Steering Line) (1/3)
| 20***70 | Plug (Only For Disconnecting Hammer) | 1 |
| 20***90 | Pressure Take-Up | 1 |
| 39***06 | Hose | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Steering Line) (2/3)
| 39***29 | Hose | 1 |
| 39***27 | Hose | 2 |
| 50***42 | Union | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Steering Line) (3/3)
| 20***85 | Pin | 4 |
| 20***40 | Clamp | 1 |
| 36***96 | Support, Assembly | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Suction Delivery Line)
| 20***90 | Pressure Take-Up | 1 |
| 36***61 | Flange | 1 |
| 39***07 | Hose | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Telescopic Arm Cylinder Line) (1/2)
| 31***21 | Bushing | 2 |
| 39***14 | Hose | 2 |
| 39***15 | Hose | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Telescopic Arm Cylinder Line) (2/2)
| 31***53 | Pipe | 1 |
| 31***54 | Pipe | 1 |
| 31***63 | Clamp | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Travel Motor Line) (1/2)
| 36***32 | Support | 1 |
| 36***24 | Union | 1 |
| 39***32 | Union | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping (Travel Motor Line) (2/2)
| 36***37 | Union | 1 |
| 36***38 | Elbow | 1 |
| 36***39 | Flange | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping Arm With Side Digging Boom (Safety Valve)
| 31***01 | Support | 1 |
| 31***16 | Union | 1 |
| 31***01 | Retainer | 2 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping Hammer (1/2)
| 31***60 | Pipe | 1 |
| 31***61 | Pipe | 1 |
| 31***62 | Support | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Piping Hammer (2/2)
| 20***54 | Coupling, Assembly | 1 |
| 20***55 | Fitting | 1 |
| 20***56 | Body | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Hydraulic Tank
| 20***40 | Indicator Oil Level | 1 |
| 20***60 | Oil Plug, Assembly | 1 |
| 36***50 | Hydraulic Tank | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Outrigger Control Lever
| 39***32 | Hose | 4 |
| 50***45 | Fastener | 1 |
| 50***04 | Union | 4 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Shovel Control Valve (1/2)
| 80***77 | Screw | 2 |
| 84***33 | Control Valve, Assembly | 1 |
| 84***69 | Tie-Rod, Assembly | 4 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Shovel Control Valve (2/2)
| 80***77 | Screw | 4 |
| 84***76 | Gasket | 2 |
| 84***81 | Kit, Support | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Transmission Hydraulic Pump (1/3)
| 80***80 | Circlip | 2 |
| 84***72 | Gasket | 1 |
| (8***2) | Pump, Assembly | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Transmission Hydraulic Pump (2/3)
| 84***40 | O-Ring | 1 |
| 84***47 | O-Ring | 2 |
| 84***50 | O-Ring | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Transmission Hydraulic Pump (3/3)
| 84***35 | Ring, Snap | 1 |
| 84***55 | O-Ring | 1 |
| 84***57 | O-Ring | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Travel Motor (1/2)
| 80***55 | Circlip | 1 |
| 80***72 | Circlip | 1 |
| 84***42 | Gasket | 1 |
Komatsu : Wb98a-2(S/N Wb98f20001-Up) : Work Equipment Control System : Travel Motor (2/2)
| 84***17 | Coil | 1 |
| 84***23 | Pin | 1 |
| 84***44 | Coil | 1 |
WB98A-2(S/N WB98F20001-Up) serial number reference
The PIN/serial plate on the WB98A-2 is riveted to the main frame on the right-hand (curb) side, typically near the front axle or below the operator's cab step, separate from the engine serial tag on the engine block. Read the plate as model code (WB98A-2) plus the serial string; the leading letters/digits before the running number (98F) identify the production block, and the digits after it are the sequential unit count within that block.
| Prefix | Identifies | Notes |
|---|---|---|
| 98F | WB98A-2 backhoe loader, base production block, S/N WB98F20001-Up | Fitted with the Komatsu S4D106-1FC diesel engine, 4-cylinder, 4.41L, rated about 72 kW (96.6 hp) net / 84 kW (113 hp) gross at 2200 rpm. Build era runs roughly 1999 through the mid-2000s. A later parts book begins at S/N WB98F20365-Up; if your unit's serial falls at or above that number, confirm with a dealer which book applies before ordering. |
Frequently asked questions
What engine does the Komatsu WB98A-2 (S/N WB98F20001-Up) use?
A Komatsu S4D106-1FC, a 4-cylinder, 4.41 L diesel. It is mechanically governed, with no electronic engine controls or onboard diagnostics, and rated at approximately 72 kW (96.5 hp).
What is the operating weight of the WB98A-2 (S/N WB98F20001-Up)?
8,290-8,750 kg (18,280-19,290 lb) as a backhoe loader, depending on configuration and ballast. Set up as a tool carrier with rear counterweight instead of the backhoe, weight runs roughly 7,700-7,970 kg (16,975-17,570 lb).
What replaced the Komatsu WB98A-2?
Komatsu moved this backhoe-loader platform to a "-5" series generation from around 2005, continuing the WB93R and WB97R model lines. The nameplate has carried forward through further generations since, with newer WB97R models the current equivalent in Komatsu's lineup.
What WB98A-2(S/N WB98F20001-Up) owners discuss
How reliable is the S4D106 diesel in the WB98A-2(S/N WB98F20001-Up), and does it have any quirks owners should know about?
Owners running this Yanmar-built four-cylinder (Komatsu-designated S4D106-1FC) describe it as quiet and long-lived when kept on a normal service interval, with machines in this family reaching well past 10,000 hours before major engine work. It is mechanically governed with a distributor-type injection pump and carries no electronic engine controls, so a no-start or rough-running complaint almost always traces back to the fuel system or glow plugs, not a sensor or module. Trapped air after a filter change is a frequent cause of hard starting: bleed the two bleed screws on the filter housing in sequence, then the screw at the injection-pump inlet. The high-pressure injector lines rarely need bleeding on their own, since any remaining air works itself out through the injectors once the low-pressure side runs clear.
The engine cranks slowly or won't catch in cold weather. What do owners check first?
Weak battery voltage and a dead or marginal glow plug are the two most commonly reported causes. A battery reading under about 12.4V struggles to spin this engine fast enough for a clean cold start, and even one weak glow plug in the bank can turn a normal start into a long crank. Check each glow plug's resistance individually rather than trusting the dash indicator alone - a plug can show as working on the light while still too weak to heat the chamber. Preheat roughly 20-30 seconds before cranking; if the engine still won't catch, recheck the glow plug circuit and battery state before chasing a fuel problem.
The forward/reverse shuttle stopped responding. Is this a known failure point on this transmission generation?
Yes, loss of forward/reverse response comes up repeatedly on this transmission generation, and it is usually electrical rather than a worn clutch pack. Owners most often trace it to the shuttle control stalk/switch or the wiring feeding the forward and reverse solenoids on the transmission valve body, not to the torque converter or gearbox itself. Because a factory replacement control column is costly and can take time to source, some owners have wired around a failed stalk by powering the solenoids directly, but that bypasses the machine's built-in shift and neutral-start safety logic and should only be a stopgap. Have your dealer verify any direct-to-solenoid workaround before returning the machine to regular duty.
Backhoe boom and dipper cylinders are weeping oil after years of service. Is that normal?
A trace of film on the rod is common as cylinders age, but a steady weep or a wet stripe down the rod means the seal is no longer sealing and should be addressed rather than just wiped down. A failed rod seal lets fluid out and lets dirt, water, and grit in past the wiper, which then scores the rod and accelerates wear on the seal, the rod itself, and eventually the pump supplying it. Treat any visible leak as a reseal job, and inspect the rod surface for pitting or scoring before assuming a seal kit alone will cure it - a scored rod will cut a new seal again quickly.
Which pins and bushings wear fastest on the loader and backhoe end of this machine?
The backhoe boom-to-dipper and dipper-to-bucket pivots see the highest cycle count of any joints on the machine and are the first place to check for play. Bucket pin bushings, on both the loader bucket and the backhoe bucket, are serviced more often than the main loader-arm or boom-foot pivots on this class of machine. Rear stabilizer pads and their pivots wear at a rate tied directly to ground conditions - abrasive or rocky sites eat them noticeably faster than clay or turf - so pad wear alone is not a reliable indicator of machine age or hours. Noticeable lateral play felt in the loader arms under load usually points to the main arm pivot bushings rather than the lift cylinders.
What electrical issues come up most often on this generation of WB loader-backhoe?
More owner complaints trace back to switches, wiring, and control-side electronics than to the engine or driveline itself, since the engine is a simple mechanical diesel with nothing electronic to fail. The forward/reverse shuttle control and its transmission solenoids are the most-cited failure point. A second recurring complaint on machines of this generation is the key-code security lockout: if the code is lost or the controller glitches, the transmission can end up electronically locked out even though the engine starts and runs fine, and clearing it typically needs a dealer reset rather than a shop-level fix. General wiring and connector corrosion in the cab and around the chassis also gets blamed for intermittent gauge, warning-light, and switch faults more often than any single failed part.
What should I check before buying a used WB98A-2(S/N WB98F20001-Up)?
Judge the machine on condition and service history over raw hours - a well-maintained unit well past 10,000 hours can be a better buy than a neglected one with far fewer. Cycle the backhoe through its full range and check the boom, dipper, and bucket pins/bushings for play, and inspect the cylinder rods for scoring or active weeping rather than just old staining. Confirm the forward/reverse shuttle shifts cleanly in both directions under load, since that control is a known weak point on this platform, and ask whether any transmission solenoid or shuttle-stalk work has already been done. Verify no key-code or security lockout is active and that the machine starts and drives away without an override. Cold-start it if possible and watch cranking speed and exhaust smoke, since a struggling cold start points to battery, glow plug, or injection-pump condition. Confirm local parts support before buying, since this platform is no longer built for the North American market and lead times on engine, transmission, and hydraulic parts can run longer than with an actively sold brand. Have your dealer verify any transmission or lockout-related repair before relying on the machine for daily work.
Compiled from owner and technician discussions across the industry — experiences vary by serial range and machine history.
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