Komatsu WA65-3(30km/h Option S/N HA940549-HA940771 & H20772-UP)
Komatsuwheel loadersmall ( - wa120 / sk*)

Komatsu WA65-3(30km/h Option S/N HA940549-HA940771 & H20772-UP)

Maintenance schedule, common problems & OEM parts breakdown

The Komatsu WA65-3 is a compact utility wheel loader, sub-5-tonne class, built for yard, landscaping, agricultural, and light construction loading work. This -3 series (built roughly 1998 to 2004) runs the Komatsu 4D94E, a mechanically governed 4-cylinder direct-injection diesel built on a Yanmar 4TNE94 block, rated 37 kW (50 PS / 50 hp) net at 2,500 rpm, with no engine ECM. Operating weight runs about 4,260 kg (9,392 lb) with the standard 0.7 cubic meter bucket, up to about 4,665 kg (10,285 lb) with the high-dump bucket fitted. Drive is Komatsu's closed-circuit hydrostatic transmission with 2 forward/2 reverse ranges, sharing one hydraulic tank with steering and loader-arm hydraulics. This specific serial bracket (HA940549-HA940771 & H20772-UP) is the factory 30 km/h travel-speed option, a running-gear/gearing variant built alongside a standard-speed (about 20 km/h) sibling in the same production window; a parallel-linkage version (WA65PT-3) was also offered on the same base chassis, plus general-purpose, light-material, 4-in-1, high-dump, side-dump, and skeleton bucket choices. Komatsu's WA65 nameplate began with a short original run before this -3 series, and the -3 generation was later succeeded by the WA65-5, a cab-standard model in a heavier weight class.

Within the -3 generation, the 30 km/h option changes only the HST gearing/travel-speed circuit; published operating weight, engine, and working dimensions carry over unchanged from the standard-speed machine built in the same serial window. The parts book still treats the two speed variants as separate entries, so axle, final-drive, and HST pump/motor parts should be confirmed against this exact serial bracket rather than assumed interchangeable with the standard-speed sibling. This -3 series was built in Germany at the former Hanomag plant in Hanover rather than in Japan, so service history and some spare-parts routing for older units trace through that European Hanomag-descended network; even the ignition key differs from later Komatsu-built machines. The WA65-5 successor moved to a cab-standard layout and a larger engine and weight class, dropping the earlier open-station and 30 km/h-option arrangement. In the used and parts market, this size and era of loader holds steady demand from landscaping, agriculture, and municipal fleets wanting a small hydrostatic-drive loader with smooth single-lever control and, on this configuration, the added road-speed transport option; the mechanically governed engine and simple drivetrain, with no ECM to fail, keep well-kept examples economical to run long after the original dealer network moved on to newer generations.

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 WA65-3(30km/h Option S/N HA940549-HA940771 & H20772-UP) specifications

Engine

ModelKomatsu 4D94E, 4-cylinder diesel, direct injection
Net power37 kW / 50 PS (50 hp) at 2,500 rpm, per ISO 9249. Gross power figure not separately published for this model.
Displacement2.775 L (2,775 cc)
Bore x stroke94 x 100 mm (3.70 x 3.94 in)
Max torque165 Nm (122 lb-ft) at 1,600 rpm
Cooling systemDual-circuit, liquid coolant, thermostat-controlled
EmissionsMeets EU/EC Stage II limits; certified to ISO 6393 exhaust/noise standard. Recognized with a low-noise environmental award for quiet operation (external LwA 96 dB(A), operator LpA 73 dB(A)).

Weights

Operating weight, standard bucket (0.7 m³ universal)4,260 kg (9,392 lb)
Operating weight, lightmaterial bucket (1.0 m³)4,355 kg (9,601 lb)
Operating weight, 4-in-1 universal bucket (0.55 m³)4,460 kg (9,833 lb)
Operating weight, high-dump bucket (1.1 m³)4,665 kg (10,285 lb)
Ground pressureNot published in available factory literature for this configuration.
Note on 30 km/h optionFactory literature lists the 30 km/h top speed as a running-gear/transmission option only; it does not change published operating weights versus the standard-speed machine.

Dimensions

Overall length (standard bucket)5,115 mm (16.8 ft); ranges up to 5,905 mm (19.4 ft) with the high-dump bucket fitted
Overall width (bucket, standard)1,850 mm (6.1 ft); up to 2,100 mm (6.9 ft) with the lightmaterial bucket
Overall height2,590 mm (8.5 ft)
Wheelbase1,950 mm (6.4 ft)
Track width (tread)1,450 mm (4.8 ft)
Ground clearance395 mm (15.6 in); 290 mm (11.4 in) on the parallel-linkage version
Minimum turning radius (outer corner of tyre)3.7 m (12.1 ft)
Frame articulation/steering angle40 degrees each side
Rear axle oscillation angle+/- 12 degrees
Centre hinge pin height3,115 mm (10.2 ft)

Performance

Travel speed, 1st gear0-5.6 km/h (0-3.5 mph)
Travel speed, 2nd gear (standard machine)0-20 km/h (0-12.4 mph)
Travel speed, this configuration (30 km/h option)0-30 km/h (0-18.6 mph), replacing the standard 2nd-range top speed. 2-speed hydrostatic transmission, shiftable in both directions under full power.
Max tipping load, straight, standard bucket2,730 kg (6,020 lb); 2,700 kg (5,952 lb) on the parallel-linkage version
Max tipping load, full articulation, standard bucket2,630 kg (5,798 lb); 2,300 kg (5,071 lb) on the parallel-linkage version
Max breakout force, standard bucket39.8 kN (8,950 lbf); 40.3 kN (9,062 lbf) on the parallel-linkage version
Max lifting capacity, standard bucket33.3 kN (7,486 lbf); 36.7 kN (8,251 lbf) on the parallel-linkage version
Max payload per EN 474-31,800 kg (3,968 lb) at 80% tipping load; 1,410 kg (3,109 lb), or 1,370 kg (3,020 lb) on the parallel-linkage version, at 60%
Hydraulic cycle timesLift 5.0 s; lower 2.4 s; dump 1.0 s
GradeabilityNot published in available factory literature for this configuration.

Service capacities (summary)

Fuel tank77.0 L (20.3 US gal)
Hydraulic system (attachment, steering, motive-power circuits)70.0 L (18.5 US gal)
Engine oil9.4 L (2.5 US gal), Komatsu EO-spec
Cooling system10.0 L (2.6 US gal)
Front axle6.1 L (1.6 US gal), Komatsu AXO-spec
Rear axle with transmission gears6.5 L (1.7 US gal), Komatsu AXO-spec

Values vary by configuration, region, and serial range — confirm against your machine before planning transport or lifts.

WA65-3(30km/h Option S/N HA940549-HA940771 & H20772-UP) fluids & capacities

SystemCapacityRecommended fluid
Engine crankcase (with filter), Komatsu 4D94E 4-cylinder diesel9.4 L (2.5 US gal)Komatsu Genuine diesel engine oil. Single-grade SAE 30 for temperate/warm ambient (roughly 0 to 40 degrees C); SAE 10W-30 for cold-climate starts down to about -20 degrees C; SAE 15W-40 all-season alternative. Match to a CD/CE-class (or later DH-series) Komatsu Genuine oil, changed with every filter service.
Cooling system (dual-circuit, liquid-cooled, thermostat-controlled)10.0 L (2.6 US gal)Komatsu Super Coolant (ethylene-glycol permanent-type antifreeze/anti-corrosion coolant), premixed to the local minimum-temperature requirement. Do not run plain water or a non-Komatsu-spec coolant, it drops the corrosion and cavitation protection built into the cooling system.
Fuel tank77.0 L (20.3 US gal)Diesel fuel only, ASTM D975 No. 2-D grade (or local equivalent). Switch to a winter-grade or No. 1-D blend in cold weather to prevent wax gelling and filter plugging.
Hydraulic system - attachment, steering and motive-power (hydrostatic drive) circuit, closed-center, includes tank70.0 L (18.5 US gal)Komatsu Genuine antiwear hydraulic oil, ISO VG46 grade (HO46-type). This single closed circuit supplies the loader/attachment hydraulics, the hydrostatic steering, and the hydrostatic transmission (motive power) together, there is no separate transmission fluid reservoir on this machine. A Komatsu Genuine bio (synthetic ester) hydraulic oil is offered as a factory option for the same circuit.
Front axle (planetary final drive + limited-slip differential, oil-bath wet disc brake)6.1 L (1.6 US gal)Komatsu Genuine axle oil, SAE 80W, GL-4/wet-brake-compatible formulation (AXO-type). Required for axles with built-in oil-bath brakes and limited-slip differential; do not substitute a plain GL-5 gear oil.
Rear axle with transmission (final-drive reduction) gears, oil-bath wet disc brake6.5 L (1.7 US gal)Same Komatsu Genuine axle oil, SAE 80W, GL-4/wet-brake-compatible formulation (AXO-type), as the front axle.
Grease points - articulation joint, loader linkage/boom pins, quick-coupler pivots, driveline U-jointsSpec only, no reservoir capacity; greased per lubrication-point scheduleKomatsu Genuine multipurpose lithium-base EP grease, NLGI No. 2. Machines with the optional automatic central lubrication system use the same grease grade fed from a central reservoir.

Capacities are refill values from factory literature — always fill to the dipstick/sight gauge, not the number.

Komatsu WA65-3(30km/h Option S/N HA940549-HA940771 & H20772-UP) maintenance schedule

Service intervalTasks
Every 50 h
  • Check engine oil level before the day's first start; top up if low.
  • Check coolant level at the radiator/reservoir; top up with the correct Super Coolant blend.
  • Check the hydraulic tank level (single circuit feeding the HST drive, steering, and loader hydraulics); top up as needed.
  • Drain water and sediment from the fuel water separator.
  • Grease the center articulation joint, loader-linkage pins, and rear-axle kingpin trunnions per the lubrication chart.
  • Walk around and check tires, lights, seatbelt, and warning lamps before startup.
Every 250 h
  • Change engine oil and the oil filter cartridge.
  • Check fan/alternator belt tension and condition; replace if cracked or glazed.
  • Check front and rear axle oil level; top up with Komatsu axle oil as needed.
  • Remove, clean, and reinstall the air cleaner element; replace if torn or clogged beyond cleaning.
  • Clean radiator and oil cooler fins of packed dirt and debris.
  • Grease all extended-interval chassis and linkage points.
Every 500 h
  • Replace the fuel filter cartridge and clean the water-separator bowl.
  • Replace the hydraulic system filter cartridge.
  • Check HST charge-circuit pressure at the test port against factory spec.
  • Replace the air cleaner outer element and inspect the safety (inner) element.
  • Check wet-disc brake pedal travel and holding function on both axles.
  • Grease extended chassis and articulation points not covered at 250 hours.
Every 1,000 h
  • Drain and refill front and rear axle oil.
  • Flush and refill the engine cooling system with fresh Super Coolant.
  • Check and adjust engine valve clearance.
  • Inspect injection nozzles for spray pattern and opening pressure.
  • Have injection pump timing checked and reset if out of spec.
  • Inspect wet-disc brake condition inside both axle housings.
Every 2,000 h
  • Change the hydraulic system oil (shared HST/steering/attachment circuit) and clean the tank breather.
  • Check Super Coolant freeze-point concentration and inspect all hoses and clamps.
  • Inspect the fuel supply (lift) pump; replace fuel and coolant hoses showing age or cracking.
  • Check and adjust fuel injection timing.
  • Inspect center-articulation bushings and rear-axle kingpin trunnions for play; replace if beyond limit.
  • Have HST charge and drive-circuit pressures tested and logged by a dealer.
Every 4,000 h
  • Inspect and, if needed, rebuild the HST charge pump and the axial-piston drive pump/motor.
  • Have the mechanical injection pump bench-tested, recalibrated, or rebuilt.
  • Rebuild wet-disc brake packs inside the front and rear axle housings if worn past limit.
  • Replace center-articulation bushings and rear-axle kingpin trunnions if play exceeds tolerance.
  • Inspect the wiring harness crossing the articulation joint for chafing; repair or reroute as needed.
  • Evaluate starter and alternator brush/bearing wear; rebuild or replace as needed.

Servicing the WA65-3(30km/h Option S/N HA940549-HA940771 & H20772-UP) beyond the schedule

Predictive Maintenance & Fluid Analysis

This WA65-3 (30 km/h option) has no engine ECM, so there are no digital fault codes; fluid sampling is the early-warning system here. Pull engine oil and hydraulic oil samples at each 250-hour service; one hydraulic tank feeds the HST charge/drive circuit, steering, and loader hydraulics, so wear shows there first. A falling HST charge pressure precedes weak push or drive-pedal creep by many hours. Watch the analog panel lamps for oil pressure, coolant temperature, and air-cleaner restriction; they are the only onboard warning this platform gives.

Corrective & Common Repairs

Weak push or creep on the HST drive is the top complaint on this loader; check charge-circuit pressure and hydraulic fluid condition before condemning the pump or motor. After any injection-pump work, verify timing marks; this mechanically governed 4D94E has no ECM to catch a mismatch, and it shows up as hard starting or knock. Center-articulation bushings and rear-axle kingpin trunnions loosen from a neglected grease schedule. Given the 30 km/h option, compare tire wear and brake condition to the standard-speed sibling, and confirm driveline parts against this exact serial bracket first.

Overhaul & Rebuild Points

At overhaul hours, rebuild the HST charge pump and axial-piston drive pump/motor once a fluid and filter service no longer restores response. Check center-articulation bushings and rear-axle kingpin trunnions for play; both flex constantly on a loader this size and wear together. Bench-test and recalibrate the mechanical injection pump if smoke or power loss appears, since there is no ECM to trim it electronically. Before ordering any axle, final-drive, or HST pump/motor part, confirm it against this exact 30 km/h-option parts-book entry; it does not interchange with the standard-speed sibling in the same serial window.

Seasonal & Environment Servicing

Match engine oil grade to season per the OMM chart: SAE 30 for warm ambient, 10W-30 for cold starts to about -20 degrees C, 15W-40 as an all-season blend. Switch to winter-grade or No. 1-D diesel to stop fuel wax gelling in cold snaps. Verify Super Coolant concentration before winter; this loader runs a small dual-circuit cooling system with little margin. In dusty yard or landscaping work, shorten the air-cleaner cleaning interval below the standard 250-hour mark. In wet climates, drain the fuel water separator daily rather than at scheduled service, to protect the mechanical injection pump.

WA65-3(30km/h Option S/N HA940549-HA940771 & H20772-UP) common service parts

Part numberPart
42U-62-12200FilterCheck fitment →
42U-62-13150Filter ElementCheck fitment →

Always confirm against your machine's serial number — cross-check any part in Heavy Parts AI before ordering.

WA65-3(30km/h Option S/N HA940549-HA940771 & H20772-UP) fault codes & troubleshooting

CodeMeaningLikely causeWhat to do
Charge Lamp (battery symbol, red)Alternator is not charging the battery circuitLoose or broken fan/alternator belt, faulty alternator, or wiring faultStop engine, check belt tension and alternator wiring before restarting
Engine Oil Pressure Lamp (oil-can symbol, red)Engine lubrication pressure has dropped below the safe thresholdLow oil level, clogged oil filter, or failing oil pumpShut engine down immediately, check oil level and filter before restart
Coolant Temperature Lamp (thermometer symbol, red)Engine coolant temperature has exceeded normal operating rangeLow coolant, clogged radiator fins, slipping fan belt, or failed thermostatIdle down, let engine cool, check coolant level and radiator before continuing work
Air Cleaner Clogging Lamp (filter symbol, red/yellow)Intake air filter restriction has reached the service limitDust-loaded air filter elementStop and inspect or replace the air filter element, check for a plugged pre-cleaner
Parking Brake Lamp (P symbol, red)Parking brake is appliedLever left engaged, or brake solenoid/switch circuit issue if lamp stays on with lever releasedConfirm lever position first; if lamp stays lit with brake released, check the parking brake switch and wiring
Brake Oil Pressure Lamp (brake symbol, red)Hydraulic brake accumulator/circuit pressure is below the safe thresholdLow hydraulic oil level, brake charge pump or accumulator fault, external leakStop machine safely using parking brake, check hydraulic oil level and brake circuit before further operation

Codes and remedies are general guidance for this model family — always confirm with diagnostic tooling and your dealer before major repairs.

WA65-3(30km/h Option S/N HA940549-HA940771 & H20772-UP) attachments & work tools

General-purpose / earth-moving bucket

Standard fitment is a 0.7 m³ (0.92 cu yd) SAE-heaped general-purpose bucket, about 1,850 mm (73 in) wide, rated near 3.5 t (7,700 lb) static tipping load straight-ahead. Sized for general earthmoving, loading, and yard work typical of this utility-class loader.

Light-material and stockpile buckets

A higher-volume light-material bucket runs about 1.0 m³ (1.3 cu yd), widened to roughly 2,100 mm (83 in), for low-density material such as mulch, sand, or grain. A stockpile bucket variant shares the same 1.0 m³ capacity for pile-handling work.

4-in-1 (universal) bucket

Optional 4-in-1 bucket holds about 0.55 m³ (0.72 cu yd) and works as clamshell, dozer blade, grab, and loader bucket in one tool, useful for grading, light dozing, and clamping bulky loads. Capacity runs lower than the standard bucket because of the internal clamshell jaw.

High-dump bucket

High-dump bucket capacity is about 1.1 m³ (1.44 cu yd) with dump height near 3.75 m (12.3 ft) at maximum dump angle, for loading over truck sideboards or into hoppers. Breakout force runs noticeably lower than the standard bucket due to the extended dump geometry.

Side-dump and mulch-grab buckets

Side-dump bucket (about 0.7 m³ / 0.92 cu yd) tips material to one side for tight-clearance work such as trenches or narrow aisles. Mulch grab bucket (also about 0.7 m³ / 0.92 cu yd) adds a hydraulic clamp arm for loose, bulky material like mulch, brush, or silage.

Skeleton (screening) bucket

Skeleton bucket uses an open bar-grate profile to sift soil, rock, or debris while loading, common in landscaping and site cleanup work. Mounts on the same coupler and auxiliary circuit as the solid buckets.

Fork carrier and pallet tines

Fork carrier with pallet tines mounts on the same quick coupler for pallet and unit-load handling; maximum stacking height with tines runs about 2.9 m (9.6 ft) and maximum reach about 1.2 m (4 ft). Fitting the optional bolt-on rear counterweight is recommended when running forks, to keep the machine stable at full reach.

Telescopic crane arm

Telescopic (jib-style) crane arm mounts on the coupler for hook-and-load lifting work, extending reach well beyond the standard boom geometry. Intended for occasional lifting duty rather than continuous crane service.

Sweeper attachment

Hydraulically driven rotary sweeper attaches through the same coupler and runs off the machine's auxiliary hydraulic circuit, used for yard, road, and site cleanup.

Quick-coupler / mounting system

Standard mounting is a hydraulic 4-point quick coupler, allowing tool changes in seconds without leaving the cab. The coupler mount is stated as cross-compatible with other-brand attachments carrying a matching interface, not limited to Komatsu Original Attachments.

Auxiliary (3rd-circuit) hydraulics

A 3rd hydraulic control circuit for attachment functions is standard, needed to run tools with a second hydraulic motion such as a clamp, sweep, or grab beyond simple tilt/lift. An electric-actuation upgrade for this 3rd circuit is offered as a factory option, along with an electronic quick-coupler lock for attachment security.

Counterweight and stability options

Factory options add front-axle ballast weights (two units, about 70 kg / 154 lb each) or a rear bolt-on counterweight (about 100 kg / 220 lb) to offset heavier attachments such as forks or the high-dump bucket. An Automatic Load Stabiliser (boom ride-damping) and an over-centre valve (boom hydraulic lock) are also offered as factory options affecting attachment handling and transport safety.

All WA65-3(30km/h Option S/N HA940549-HA940771 & H20772-UP) assemblies by section

Every catalogued assembly group for the Komatsu WA65-3(30km/h Option S/N HA940549-HA940771 & H20772-UP). Open an assembly to preview the parts inside — full OEM part numbers are available in Heavy Parts AI.

03 Electric System
Komatsu : Wa65-3(30km/H Option S/N Ha940549-Ha940771 & H20772-Up) : 03 Electric System : 62 Electric System, Relay
01***10Screw,(For Lighter)4
01***10Screw,(For Wiper Switch Earth)2
01***12Screw,(With Articulate Indicator)3
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Komatsu : Wa65-3(30km/H Option S/N Ha940549-Ha940771 & H20772-Up) : 03 Electric System : 63 Instrument Box And Instruments
42***01Key Kit1
42***10Starter Switch1
42***30Symbol1
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Komatsu : Wa65-3(30km/H Option S/N Ha940549-Ha940771 & H20772-Up) : 03 Electric System : 80 Licence Plate Light
01***10Screw,(For Lighter)4
01***16Screw, Mount Parking Lights2
42***00Licence Plate Light2
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04 Transmission, Universal Joint
Komatsu : Wa65-3(30km/H Option S/N Ha940549-Ha940771 & H20772-Up) : 04 Transmission, Universal Joint : 61 Axial Piston Pump
42***20Screw4
42***01Axial Piston Pump1
42***00Pump1
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Komatsu : Wa65-3(30km/H Option S/N Ha940549-Ha940771 & H20772-Up) : 04 Transmission, Universal Joint : 75 Universal Joint
42***10Universal Joint1
42***01Lubrication Nipple2
42***30Nut12
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Komatsu : Wa65-3(30km/H Option S/N Ha940549-Ha940771 & H20772-Up) : 04 Transmission, Universal Joint : 93 Gear Box Controls
01***45Screw4
01***25Screw2
01***20Bolt - Mount Risers To Cab Floor2
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Komatsu : Wa65-3(30km/H Option S/N Ha940549-Ha940771 & H20772-Up) : 04 Transmission, Universal Joint : 97 Hydraulic Pump Drive
01***20Screw1
01***12Bolt - M8 - 1.25 X 121
01***10Screw2
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Komatsu : Wa65-3(30km/H Option S/N Ha940549-Ha940771 & H20772-Up) : 04 Transmission, Universal Joint : 98 Axial Piston Engine
42***62Grub Screw2
42***01Axial Piston Engine1
42***58Plug2
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05 Rear Axle
Komatsu : Wa65-3(30km/H Option S/N Ha940549-Ha940771 & H20772-Up) : 05 Rear Axle : 43 Rear Axle
01***16Nut - M208
42***00Rear Axle1
42***30Disc8
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12 Tools, Accessory, Lettering
Komatsu : Wa65-3(30km/H Option S/N Ha940549-Ha940771 & H20772-Up) : 12 Tools, Accessory, Lettering : 03 Lettering
09***81Plate? Caution,Don'T Jump Start1
42***80Note Plate1
42***80Note Plate1
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15 Equipment
Komatsu : Wa65-3(30km/H Option S/N Ha940549-Ha940771 & H20772-Up) : 15 Equipment : 62 A.L.S. Equipment
01***16Bolt - Seat And Tether Belt Mounting3
01***50Screw2
01***20Bolt, Hose Clamps (Inlet And Return Line Hoses)4
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WA65-3(30km/h Option S/N HA940549-HA940771 & H20772-UP) serial number reference

The PIN/serial plate on Komatsu WA-series wheel loaders, including the WA65-3, is mounted on the frame's right-hand (curb) side, typically behind the front fender or under the edge of the operator's cab. Komatsu also stamps the number directly into the frame steel near the plate as a backup if the plate is lost or painted over. This model's production run carries two serial threads: an older-style chassis serial (letter+digits, e.g. HA940xxx) used through part of the run, then a newer numeric-prefix continuation PIN (H2 + digits) picked up later in the run. The 30km/h travel-speed option is a factory build/option code, not a guaranteed distinct serial sub-range - Komatsu's own catalog groups both the option and non-option machines under overlapping serial windows, so read the full PIN plate and verify the actual option fitted with a Komatsu dealer rather than assuming configuration from the serial number alone.

PrefixIdentifies
HA940549-HA940771WA65-3, 30km/h travel-speed option
H20772-UPWA65-3, 30km/h travel-speed option (post-changeover PIN)

Frequently asked questions

What engine powers this Komatsu WA65-3 (30 km/h option)?

The Komatsu 4D94E, a 4-cylinder direct-injection diesel built on a Yanmar 4TNE94 block. It is mechanically governed with no engine ECM, rated 37 kW (50 PS / 50 hp) net at 2,500 rpm from 2.775 L displacement. This is the same engine as the standard-speed WA65-3 built in the same serial window; the 30 km/h option changes only the HST travel-speed gearing, not the engine.

What is the operating weight of this WA65-3 configuration?

About 4,260 kg (9,392 lb) with the standard 0.7 cubic meter bucket. Operating weight runs higher with other factory buckets fitted, up to roughly 4,665 kg (10,285 lb) with the high-dump bucket. The 30 km/h option does not change the published operating weight versus the standard-speed sibling in the same serial range.

What replaced this WA65-3?

Komatsu's WA65-5 followed this -3 series. It moved to a cab-standard configuration and stepped up into a heavier weight class, around 4.7 t, with a larger engine (a roughly 40 kW / 54 hp class unit) than this -3 series' 4D94E. No 30 km/h-option variant is documented under the WA65-5 nameplate; confirm exact configuration with your dealer.

What WA65-3(30km/h Option S/N HA940549-HA940771 & H20772-UP) owners discuss

How does this loader's hydrostatic drive change the way it handles compared to a torque-converter machine?
This WA65-3 runs a closed-circuit hydrostatic transmission (2 forward/2 reverse ranges), not a torque-converter powershift. Response to the travel pedal is more direct, the machine holds ground speed downhill through engine braking, and there is no converter creep to fight when sitting on a grade. The tradeoff owners report: a hydrostatic drive is less forgiving of low fluid or contaminated oil, because the charge pump and drive pump share one closed loop. A starved suction side shows up first as sluggish acceleration or weaker push into the pile, well before an outright failure.
What engine is under the hood, and what should a mechanic know going in?
This 30 km/h-option WA65-3 (S/N HA940549-HA940771 & H20772-up) is fitted with the 4-cylinder 4D94E diesel, built on the Yanmar 4TNE94 block, rated around 37 kW (50 PS) net. It uses a mechanical injection pump, not an electronic common-rail system, so there is no ECM and no fault-code memory to pull. Diagnosis is old-school: injector condition, pump timing, and fuel filtration. If the injection pump is ever pulled for overhaul, timing marks must line up with the correct set — some rebuilt pumps arrive under-marked, and a mismatch shows up immediately as hard starting or a heavy knock. Have your dealer or a qualified diesel shop verify pump timing after any injection-system work.
People mention hydrostatic 'creep' or weak push on loaders like this. What's usually behind it?
Across Komatsu's compact hydrostatic-drive loaders of this era, the recurring failure story is the same: the charge pump wears first, and once charge pressure drops, the drive circuit can't hold the pump swashplate cleanly in neutral. Symptoms are the loader wanting to creep when parked in neutral, and progressively softer push into a pile as internal leakage rises. A pressure check at the charge circuit (compared to spec at idle and at full throttle), plus a look at the inline HST filter for metal fines, settles the diagnosis quickly. This is drivetrain-critical repair work — have your dealer verify pressures before condemning a pump or motor.
Are there undercarriage or structural wear points typical for a loader this size?
Same pattern as any articulated wheel loader: the center articulation pins/bushings and the kingpin/oscillation trunnions at the rear axle take the abuse. Grease intervals matter more on a machine this size because the joint has less material margin before play becomes noticeable. A rocking test at the hitch with the machine parked straight — engine off, one person watching the joint while another applies steering-cylinder pressure by hand — is the standard used-buyer check. Loose articulation play paired with uneven front-tire wear points to a neglected grease schedule rather than a design fault.
What's different about buying a used one of these versus a Japan-built Komatsu loader?
The whole WA65-3/WA75-3/WA95-3 compact-loader family, including this 30 km/h-option range, was built in Germany at the former Hanomag plant in Hanover, not in Japan. Parts and service history for older units can route through the European Hanomag-descended network rather than the standard Komatsu Japan supply chain. Even the ignition lock is different: the universal Komatsu spare key that starts most other Komatsu machines will not start these early German-built compact loaders. Worth knowing before assuming a spare key from another Komatsu unit will work, and worth flagging to whoever sources parts.
What should I check specifically because this unit carries the 30 km/h option?
Komatsu offered this WA65-3 in two travel-speed configurations: a standard machine around 20 km/h (12.5 mph) and this 30 km/h option, covering S/N HA940549-HA940771 and H20772-up. The two configurations sit in separate parts-book entries, meaning some driveline components differ even though the machines look identical from outside. Do not assume axle, final-drive, or hydrostatic pump/motor parts interchange between the standard and 30 km/h version without checking the parts book against this exact serial bracket. Given the added road speed, also compare tire wear and brake condition against a standard-speed machine of similar age. Have your dealer verify the exact driveline parts break for your specific serial number before ordering anything.
What about brakes and cylinder condition on an older example of this loader?
Komatsu marketed the hydrostatic drive as giving low-maintenance braking, since the drive itself provides strong engine braking and the wheel brakes see lighter duty than on a torque-converter machine. That is not a reason to skip a brake check on a used unit, especially one that has sat idle for a stretch. Loader-arm and bucket cylinder seals are the other common owner complaint on a machine this age: rod seal weep shows up as an oil film on the exposed rod, and a raised bucket that settles down overnight points to the same wear. Neither issue is unique to this model, but both are cheap to check during a pre-purchase walk-around and expensive to ignore afterward. Have your dealer verify parking-brake holding force if the machine has sat unused for an extended period.

Compiled from owner and technician discussions across the industry — experiences vary by serial range and machine history.

Serial-range & configuration variants

This page covers the Komatsu WA65-3(30km/h Option S/N HA940549-HA940771 & H20772-UP). Related factory variants of the same model family:

WA65-3(S/N HA940051-HA940548)WA65-3(S/N HA940549-HA940771 & H20761-UP)

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