Komatsu WA80-5(S/N H50051-UP)
Maintenance schedule, common problems & OEM parts breakdown
The Komatsu WA80-5 (S/N H50051-UP) is a compact articulated wheel loader in Komatsu's long-running WA series, sized between the smaller WA65-5/WA70-5 and the larger WA90/WA100M compact loaders it shares a shop manual with. It runs the naturally aspirated, mechanically governed Komatsu 4D95LE-3 four-cylinder diesel, about 3.3 L displacement and rated near 45 kW (60 HP) at 2,350 rpm, with no electronic engine control. Operating weight is around 5,640 kg (12,430 lb) in standard trim and can run up to roughly 5.9 t (13,000 lb) depending on bucket, counterweight, and tire fitment. Drive is through a hydrostatic transmission with full power shift in both directions, paired with an articulated, oscillating-rear-axle chassis, hydrostatic steering, and a longitudinally mounted engine under a tilting hood for service access. This S/N H50051-UP block covers WA80-5 production through the mid-to-late 2000s, sitting between earlier WA80-generation loaders and the WA80-6 that replaced it around 2008. Komatsu offered it with a standard general-purpose bucket (about 0.9 m3 / 1.2 cu yd) or a larger light-material bucket (up to about 1.25 m3 / 1.6 cu yd), plus fork carriers, a 4-in-1 bucket, and a quick coupler for fast attachment changes, in canopy or enclosed-cab form.
Across the WA80 line, the -5 generation's defining break from what came before and after is the powertrain: this model keeps a simple, mechanically governed, naturally aspirated engine with no ECM, while the WA80-6 that followed moved to a turbocharged, electronically managed variant of the same engine family with more power and different service electronics. That makes the WA80-5 effectively the last loader of this size you can run and troubleshoot without a factory diagnostic laptop, which keeps it in demand with independent shops, landscapers, rental yards, and municipalities that want a compact, four-wheel, hydrostatic-drive loader without emissions-era electronics to manage. On the used and parts market, values track hard against hour meter reading, hydrostatic pump and motor condition, and axle and brake wear rather than software or emissions history. Because the mechanical fuel system, HST components, and axle design are shared across the WA65-5/WA70-5/WA80-5 family, parts sourcing and shop familiarity carry over well between these siblings, which keeps practical support for the WA80-5 reasonably strong well after production ended.
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 WA80-5(S/N H50051-UP) specifications
Engine
| Engine model | Komatsu 4D95LE-3, inline 4-cylinder diesel, naturally aspirated |
| Net power | 45 kW / 60 HP (SAE J1349) at 2,350 rpm |
| Maximum torque | 214 Nm (158 lb-ft) at 1,600 rpm |
| Displacement | 3.29 L (3,294 cc / 201 cu in), 4 cylinders |
| Emissions certification | Not published in available spec sheets for this engine arrangement. Confirm the certified emissions level for this serial range with your dealer. |
Weights
| Operating weight | 5,640 kg (12,434 lb) with standard bucket fitted |
| Static tipping load, straight | 4,325 kg (9,534 lb) |
| Static tipping load, full turn | 3,690 kg (8,135 lb) |
| Shipping weight | Not separately published; use operating weight for transport planning and verify with dealer for crated/knocked-down figures |
Dimensions
| Overall length, bucket on ground | 5.49 m (18.0 ft) |
| Overall width over tires | 1.88 m (6.17 ft) |
| Overall height to top of cab | 2.67 m (8.75 ft) |
| Wheelbase | 2.19 m (7.17 ft) |
| Ground clearance | 0.30 m (1.0 ft) |
| Turning radius (outside, over tires) | 3.81 m (12.5 ft) |
| Standard tire size | 405/70-18 |
Performance
| Travel speed | 20 km/h (12.4 mph) on the standard transmission. A 30 km/h (18.6 mph) high-speed transmission option is documented under this same serial range in factory parts literature; confirm which transmission is fitted to a given unit |
| Bucket breakout force | 45.2 kN (10,164 lbf) |
| Static bucket lifting force | 50.3 kN (11,310 lbf) |
| Bucket raise time | 4.9 sec |
| Bucket dump time | 0.9 sec |
| Gradeability | Not published in available spec sheets for this model |
Service capacities (summary)
| Fuel tank | 84 L (22.2 US gal) |
| Hydraulic system, total | 29.9 L (7.9 US gal) |
| Engine oil, with filter | 7.6 L (2.0 US gal) |
| Cooling system | 9.1 L (2.4 US gal) |
| Front/rear axle (differential/final drive), each | 8.7 L (2.3 US gal) |
Values vary by configuration, region, and serial range — confirm against your machine before planning transport or lifts.
WA80-5(S/N H50051-UP) fluids & capacities
| System | Capacity | Recommended fluid |
|---|---|---|
| Engine crankcase (with filter) | 7.6 L (2.0 US gal) | Komatsu Genuine diesel engine oil (EO series). Grade by ambient air temperature at startup: SAE10W below freezing, SAE10W30 for temperate range, SAE15W40 for warm climates, SAE30 for sustained heat. Meets API/JASO diesel engine oil spec for this engine generation. |
| Cooling system | 9.1 L (2.4 US gal) | Komatsu Supercoolant AF-NAC permanent-type antifreeze/coolant, factory-filled. Mix ratio set by regional minimum ambient temperature; do not mix with other coolant brands or types. |
| Fuel tank | 84 L (22.2 US gal) | ASTM D975 No. 2-D diesel fuel for normal service; switch to No. 1-D (or winter-grade blend) in cold climates to prevent wax/gelling. Use low-sulfur fuel matching the engine's emissions certification. |
| Hydrostatic transmission / hydraulic system (incl. tank) | 29.9 L (7.9 US gal) | Komatsu Genuine hydraulic oil (HO series), graded by ambient temperature (lighter ISO-VG grade in cold climates, heavier in hot climates). This loader's hydrostatic drive circuit shares the main hydraulic reservoir; no separate transmission fill point is documented for this model. Do not substitute biodegradable oils without dealer confirmation of compatibility. |
| Front axle & differential (incl. wheel-end final drives) | 8.7 L (2.3 US gal) | Komatsu Genuine axle oil (AXO series), SAE80W90 GL-5 gear oil. |
| Rear axle & differential (incl. wheel-end final drives) | 8.7 L (2.3 US gal) | Komatsu Genuine axle oil (AXO series), SAE80W90 GL-5 gear oil. |
| Grease points (linkage pins, bushings, articulation joint) | Not a fill-volume item — service per lube chart interval | Komatsu Genuine multipurpose lithium EP2 grease (G2-LI). Use molybdenum-disulfide grease only where the OMM lube chart calls it out for a specific point. |
Capacities are refill values from factory literature — always fill to the dipstick/sight gauge, not the number.
Komatsu WA80-5(S/N H50051-UP) maintenance schedule
| Service interval | Tasks |
|---|---|
| Every 50 h |
|
| Every 250 h |
|
| Every 500 h |
|
| Every 1,000 h |
|
| Every 2,000 h |
|
| Every 4,000 h |
|
Servicing the WA80-5(S/N H50051-UP) beyond the schedule
Predictive Maintenance and Fluid Analysis
Because the 4D95LE-3 runs no ECM, there is no fault-code history to lean on, so hour-based sampling is the primary early-warning tool. Pull engine oil, HST case-drain oil, and axle oil samples at scheduled intervals and watch for water intrusion in the hydrostatic charge circuit, a common failure entry point, and for metal count trending up in axle differential oil. Track coolant condition to catch scale before the compact radiator core plugs, and log hydraulic oil cleanliness, since the WA80-5's HST system is sensitive to contamination.
Corrective and Common Repairs
Most WA80-5 corrective work centers on the hydrostatic drive and the articulation joint. Watch for HST charge-pump wear causing sluggish creep speed or a loss of power in one travel direction, and check the input-shaft seal area for case leakage where aging pump housings work loose. Center articulation pins and bushings wear from constant steering load in tight yard work, so check for play at the pivot before it transfers into the frame. Wet brake discs and steering cylinder pins are the other recurring wear points on this chassis.
Overhaul and Rebuild Points
At higher hours, rebuild attention on the WA80-5 focuses on the HST pump and motor pair, the front and rear axle differentials, and the naturally aspirated 4D95LE-3's injection pump and injectors. Valve clearance and injector calibration drift over time on this mechanically governed engine and should be checked during any major service, not only after a failure. Axle housings on this chassis absorb heavy shock load from loader-bucket work, so bearing and gear wear should be inspected alongside any HST rebuild rather than treated as a separate job.
Seasonal and Environment Servicing
Cold-weather operation on the WA80-5 needs correct-viscosity engine oil and adequate coolant freeze protection, since the naturally aspirated, mechanically governed 4D95LE-3 has no electronic cold-start assist beyond a basic intake air heater. In hot or dusty environments, the compact engine bay and radiator and oil-cooler stack clog quickly, so clean screens and cores more often than the standard interval. Because this is a wheeled, articulated machine, seasonal tire pressure checks and wet-brake oil condition matter as much as engine service, especially where the loader works wet yards or salted surfaces.
WA80-5(S/N H50051-UP) common service parts
| Part number | Part | Notes | |
|---|---|---|---|
| 6204-71-7200 | Fuel Filter | Fuel system service | Check fitment → |
| 42U-01-13170 | Air Filter | Air intake service | Check fitment → |
| 07000-02135 | O-Ring,Hydraulic Oil Filter | Hydraulic service | Check fitment → |
| 600-311-2110 | Filter Element | Scheduled service item | Check fitment → |
| 6204-71-7210 | Filter Head | Scheduled service item | Check fitment → |
Always confirm against your machine's serial number — cross-check any part in Heavy Parts AI before ordering.
WA80-5(S/N H50051-UP) fault codes & troubleshooting
| Code | Meaning | Likely cause | What to do |
|---|---|---|---|
| Engine Oil Pressure Warning Lamp (red, engine symbol) | Engine lubrication oil pressure has dropped below the safe minimum. | Low oil level, clogged oil filter, worn oil pump, or a faulty pressure sender or wiring. | Stop the engine immediately. Check oil level and filter condition before restarting. |
| Battery Charge Warning Lamp (battery symbol) | Alternator is not charging the battery circuit. | Loose or worn fan/alternator belt, failed alternator, or a loose or corroded wiring connection. | Check belt tension and battery terminals first, then test alternator output. |
| Coolant Temperature Gauge in red zone | Engine coolant temperature has exceeded the normal operating range. | Low coolant level, clogged radiator core or screen, failed thermostat, or a slipping fan belt. | Idle the engine to cool down, then check coolant level, radiator fins, and belt once it is safe to do so. |
| Torque Converter Oil Temperature Caution Lamp | Transmission and torque converter oil is running hot. | Low oil level, clogged oil cooler, or prolonged stall-condition operation during heavy digging or loading. | Reduce load and let the converter cool at low idle, then check oil level and cooler for blockage. |
| Air Cleaner Restriction Indicator | Intake air filter restriction has reached the service limit. | Dirty or clogged air filter element. | Inspect the element and clean or replace it. |
| Parking Brake Warning Lamp | Parking brake is applied, or its circuit shows a fault. | Parking brake lever left engaged, low brake circuit pressure, or a faulty switch. | Confirm the parking brake lever position; if the lamp stays on with the brake released, check the switch and linkage. |
| Fuel Level Gauge - low/empty | Fuel tank level is critically low. | Machine operated near empty on fuel. | Refuel promptly. If the engine has run out of fuel, bleed air from the mechanical injection fuel system before restarting. |
Codes and remedies are general guidance for this model family — always confirm with diagnostic tooling and your dealer before major repairs.
WA80-5(S/N H50051-UP) attachments & work tools
Universal bucket
Standard work tool is a 0.9 m³ (SAE heaped) universal bucket, roughly 1.91 m wide. A 1.25 m³ variant is also offered for general loading and light excavation duty.
Light-material bucket
Higher-volume, lower-density buckets at 1.0 m³ and 1.25 m³ for bulky, low-density material such as mulch or loose aggregate where cubic capacity matters more than payload weight.
4-in-1 (multi-purpose) bucket
0.8 m³ combination bucket that dozes, grades, clamshell-grabs, and loads with one tool, operated through a two-way bucket cylinder.
High-dump bucket
1.1 m³ bucket with a raised dump point for clearing truck sideboards or loading into hoppers on this class of compact loader.
Mulch grapple bucket
0.7 m³ hydraulic clamping grapple bucket for handling loose or bulky organic material such as brush, mulch, or debris.
Side-dump bucket
0.7 m³ bucket that discharges to the side instead of forward, useful for backfilling or loading in tight aisles without swinging the machine.
Pallet forks
Optional fork carrier and tines rated for a forklift payload around 2,200 kg, versus roughly 1,850 kg standard-bucket payload. Fork geometry keeps tines level through the lift without constant operator readjustment.
Quick coupler / hydraulic hitch
Market-compatible hydraulic quick coupler is standard, with ISO 16028-type quick connectors offered as an option. All listed buckets and attachments mount through this coupler for fast changeover from the cab.
Sweeper
Optional broom attachment mounted through the same quick-coupler system, used for yard and hard-surface cleanup rather than digging duty.
Load stabilizer (ECSS)
Optional electronically controlled hydro-pneumatic boom damping system. Smooths ride and reduces load spillage when traveling with a full bucket or heavy attachment over rough ground.
Locking differentials
Optional 100% manual front and rear differential locks improve traction when running attachments such as forks or grapples in soft, loose, or uneven ground.
Operator guarding
Standard ROPS/FOPS cab structure built to EN474 machinery safety requirements, relevant when running attachments with falling-object or debris exposure such as grapple or sweeper work.
All WA80-5(S/N H50051-UP) assemblies by section
Every catalogued assembly group for the Komatsu WA80-5(S/N H50051-UP). Open an assembly to preview the parts inside — full OEM part numbers are available in Heavy Parts AI.
01 Engine, Engine Mounting
Komatsu : Wa80-5(S/N H50051-Up) : 01 Engine, Engine Mounting : 01 Engine, Engine Mounting
| 01***95 | Screw | 2 |
| 01***10 | Screw | 2 |
| 01***25 | Bolt, Mount Engine Oil Drain To Fuel Tank | 8 |
Komatsu : Wa80-5(S/N H50051-Up) : 01 Engine, Engine Mounting : 02 Cylinder Block And Attaching Parts
| 04***20 | Pin,Dowel (Welded) | 2 |
| 04***28 | Pin, Dowel - Transmission Case, Pin-Dowel | 2 |
| 04***08 | Adapter Sleeves | 6 |
Komatsu : Wa80-5(S/N H50051-Up) : 01 Engine, Engine Mounting : 04 Crank Assembly
| 01***45 | Bolt,Nylock | 1 |
| 61***31 | Plate | 1 |
| 62***00 | Main Metal Ass'Y | 5 |
Komatsu : Wa80-5(S/N H50051-Up) : 01 Engine, Engine Mounting : 05 Cylinder Head And Attaching Parts
| 01***20 | Bolt, Hose Clamps (Inlet And Return Line Hoses) | 4 |
| 02***04 | Plug, Pipe | 1 |
| 07***08 | Plug, Expansion | 4 |
Komatsu : Wa80-5(S/N H50051-Up) : 01 Engine, Engine Mounting : 07 Cylinder Head Cover, Attaching Parts
| 61***10 | Cap, Oil Filler | 1 |
| 61***20 | Screw | 3 |
| 61***30 | Washer,(B) | 3 |
Komatsu : Wa80-5(S/N H50051-Up) : 01 Engine, Engine Mounting : 08 Timing Gear Case And Flywheel Housing
| 01***16 | Bolt, Mounting Transmission Control Switch | 2 |
| 01***16 | Bolt, Mount Solenoid Valve | 2 |
| 01***55 | Screw | 11 |
Komatsu : Wa80-5(S/N H50051-Up) : 01 Engine, Engine Mounting : 09 Engine Timing Gear
| 01***20 | Bolt,(Forwarded Individually Parts) | 2 |
| 01***70 | Bolt,(For 75a Alternator) | 1 |
| 04***16 | Fitting Wedge | 1 |
Komatsu : Wa80-5(S/N H50051-Up) : 01 Engine, Engine Mounting : 10 Engine Lubrication
| 01***16 | Bolt, Mount Solenoid Valve | 4 |
| 01***25 | Bolt - Relay Mounting | 1 |
| 07***59 | Clamp,See Fig. K4010-05a0 | 4 |
Komatsu : Wa80-5(S/N H50051-Up) : 01 Engine, Engine Mounting : 15 Water Pump
| 01***16 | Screw | 6 |
| 01***14 | Bolt,(W/Joy Stick Str.)(W/O Heater) | 4 |
| 01***20 | Bolt,(Forwarded Individually Parts) | 2 |
Komatsu : Wa80-5(S/N H50051-Up) : 01 Engine, Engine Mounting : 20 Injection System
| 01***30 | Stud Bolt | 2 |
| 01***12 | Bolt,(See Fig. K0210-16a0) | 1 |
| 01***25 | Screw | 2 |
Komatsu : Wa80-5(S/N H50051-Up) : 01 Engine, Engine Mounting : 24 Injection Pump, Body Pump
| 14***00 | O-Ring | 1 |
| 14***00 | Shim | 0 |
| 62***90 | Injection Pump | 1 |
Komatsu : Wa80-5(S/N H50051-Up) : 01 Engine, Engine Mounting : 28 Fuel System, Pre Filter
| 01***45 | Bolt,Nylock | 1 |
| 61***31 | Plate | 1 |
| 62***00 | Main Metal Ass'Y | 5 |
Komatsu : Wa80-5(S/N H50051-Up) : 01 Engine, Engine Mounting : 49 Air Filter System, Standard
| 01***30 | Bolt,(Water Separator Spec.) | 2 |
| 01***06 | Nut,(With Back-Up Alarm) (Op), Nut; Was 01580-10806 | 2 |
| 01***12 | Washer,(With Body Positioner) | 2 |
Komatsu : Wa80-5(S/N H50051-Up) : 01 Engine, Engine Mounting : 54 Air Cleaner
| 42***70 | Air Filter | 1 |
| 42***01 | Filter Element | 1 |
| 42***02 | Filter Element | 1 |
Komatsu : Wa80-5(S/N H50051-Up) : 01 Engine, Engine Mounting : 57 Exhaust System
| 01***20 | Bolt, Hose Clamps (Inlet And Return Line Hoses) | 9 |
| 42***00 | Silencer | 1 |
| 42***20 | Gasket | 1 |
02 Cooling System
Komatsu : Wa80-5(S/N H50051-Up) : 02 Cooling System : 73 Radiator
| 01***16 | Bolt, Mount Solenoid Valve | 6 |
| 01***30 | Bolt - Lower Oil Cooler Outlet Tubemounting | 4 |
| 01***06 | Nut,(With Back-Up Alarm) (Op), Nut; Was 01580-10806 | 6 |
Komatsu : Wa80-5(S/N H50051-Up) : 02 Cooling System : 74 Radiator Attaching Parts
| 01***40 | Screw, Hex Socket | 2 |
| 01***16 | Bolt, Mount Solenoid Valve | 5 |
| 01***20 | Bolt,(Forwarded Individually Parts) | 4 |
03 Electric System
Komatsu : Wa80-5(S/N H50051-Up) : 03 Electric System : 42 Alternator
| 01***95 | Bolt (M10-1.50x95) | 1 |
| 01***25 | Bolt - Relay Mounting | 2 |
| 01***30 | Bolt,(Water Separator Spec.) | 1 |
Komatsu : Wa80-5(S/N H50051-Up) : 03 Electric System : 43 Starter Motor
| 01***35 | Bolt,R.H. (For Add. Air Compressor) | 2 |
| 60***50 | Startermotor | 1 |
Komatsu : Wa80-5(S/N H50051-Up) : 03 Electric System : 56 Electric System, Lighting Unit
| 01***16 | Screw, Mount Parking Lights | 4 |
| 01***16 | Bolt, Mount Solenoid Valve | 1 |
| 01***16 | Bolt - Starting Motor Ground Cable | 2 |
Komatsu : Wa80-5(S/N H50051-Up) : 03 Electric System : 61 Electric System, Harness
| 01***16 | Bolt - Starting Motor Ground Cable | 7 |
| 04***10 | Clip,(With Accumulator) | 1 |
| 04***10 | Clip,(Without Cab) | 1 |
Komatsu : Wa80-5(S/N H50051-Up) : 03 Electric System : 62 Electric System, Relay
| 01***16 | Screw,(Sandy And Dusty Terrain S.) | 4 |
| 01***10 | Screw,(For Wiper Switch Earth) | 3 |
| 01***12 | Screw,(With Articulate Indicator) | 5 |
Komatsu : Wa80-5(S/N H50051-Up) : 03 Electric System : 63 Instrument Box And Instruments
| 42***23 | Plain Washer | 2 |
| 42***01 | Orifice Plate | 2 |
| 42***36 | Orifice Plate | 4 |
Komatsu : Wa80-5(S/N H50051-Up) : 03 Electric System : 65 Windshield-Wiper - Washer System
| 01***16 | Bolt, Mounting Transmission Control Switch | 4 |
| 01***05 | Nut,(For Air Conditioner Less), Nut | 4 |
| 08***34 | Tie, Cable | 3 |
Komatsu : Wa80-5(S/N H50051-Up) : 03 Electric System : 74 Battery
| 01***16 | Bolt, Mount Solenoid Valve | 2 |
| 01***16 | Bolt - Starting Motor Ground Cable | 4 |
| 04***10 | Clip | 1 |
04 Transmission, Universal Joint
Komatsu : Wa80-5(S/N H50051-Up) : 04 Transmission, Universal Joint : 61 Axial Piston Pump
| 42***01 | Pump | 1 |
| 42***02 | Variator | 1 |
| 42***03 | Control | 1 |
Komatsu : Wa80-5(S/N H50051-Up) : 04 Transmission, Universal Joint : 75 Universal Joint
| 42***20 | Screw | 12 |
| 42***10 | Universal Joint | 1 |
Komatsu : Wa80-5(S/N H50051-Up) : 04 Transmission, Universal Joint : 83 Clutch
| 01***25 | Bolt,(For Canvas Canopy?Head Guard) | 8 |
| 01***25 | Bolt,Sight | 12 |
| 42***10 | Coupling/Clutch | 1 |
Komatsu : Wa80-5(S/N H50051-Up) : 04 Transmission, Universal Joint : 98 Axial Piston Engine
| 42***20 | Screw | 12 |
| 42***10 | Universal Joint | 1 |
05 Rear Axle
Komatsu : Wa80-5(S/N H50051-Up) : 05 Rear Axle : 43 Rear Axle
| 01***90 | Screw | 8 |
| 42***00 | Nut | 16 |
| 42***10 | Rear Axle | 1 |
Komatsu : Wa80-5(S/N H50051-Up) : 05 Rear Axle : 44 Axle Insert
| 42***55 | Shim | 0 |
| 42***56 | Shim | 0 |
| 42***57 | Shim | 0 |
Komatsu : Wa80-5(S/N H50051-Up) : 05 Rear Axle : 45 Differential
| 42***74 | Bevel Gear | 1 |
| 42***75 | Shank | 2 |
| 42***76 | Shim | 4 |
Komatsu : Wa80-5(S/N H50051-Up) : 05 Rear Axle : 46 Differential
| 42***75 | Shank | 2 |
| 42***76 | Shim | 4 |
| 42***80 | Screw | 2 |
06 Disc Wheel, Chain
Komatsu : Wa80-5(S/N H50051-Up) : 06 Disc Wheel, Chain : 77 Disc Wheel
| 42***10 | Valve | 4 |
| 42***20 | Rim | 4 |
| 42***20 | Rim | 4 |
07 Steering
Komatsu : Wa80-5(S/N H50051-Up) : 07 Steering : 07 Steering Cylinder
| 01***20 | Bolt, Hose Clamps (Inlet And Return Line Hoses) | 2 |
| 41***80 | Union | 2 |
| 42***20 | Stud | 4 |
08 Front Axle
Komatsu : Wa80-5(S/N H50051-Up) : 08 Front Axle : 00 Front Axle
| 42***00 | Nut | 16 |
| 42***90 | U Bolt | 2 |
| 42***10 | Front Axle | 1 |
Komatsu : Wa80-5(S/N H50051-Up) : 08 Front Axle : 01 Axle Insert
| 42***51 | Screw | 2 |
| 42***54 | Drive | 1 |
| 42***55 | Shim | 6 |
Komatsu : Wa80-5(S/N H50051-Up) : 08 Front Axle : 02 Differential
| 42***74 | Bevel Gear | 1 |
| 42***75 | Shank | 2 |
| 42***76 | Shim | 4 |
09 Brake System
Komatsu : Wa80-5(S/N H50051-Up) : 09 Brake System : 00 Brake System
| 01***16 | Bolt, Mounting Transmission Control Switch | 2 |
| 01***20 | Bolt,(Forwarded Individually Parts) | 4 |
| 01***16 | Bolt - Starting Motor Ground Cable | 2 |
Komatsu : Wa80-5(S/N H50051-Up) : 09 Brake System : 90 Hand Brake And Operating Assembly
| 01***16 | Bolt - Starting Motor Ground Cable | 3 |
| 01***12 | Washer,(With Body Positioner) | 1 |
| 04***15 | Pin,Cotter (Itl) | 1 |
10 Frame
Komatsu : Wa80-5(S/N H50051-Up) : 10 Frame : 02 Frame
| 01***40 | Screw | 2 |
| 01***20 | Bolt,(Forwarded Individually Parts) | 4 |
| 01***45 | Washer,(For Travel Motor) (Not Show) | 2 |
Komatsu : Wa80-5(S/N H50051-Up) : 10 Frame : 03 Hinge
| 01***35 | Screw | 1 |
| 01***80 | Screw | 1 |
| 01***35 | Bolt,R.H. (For Add. Air Compressor) | 4 |
Komatsu : Wa80-5(S/N H50051-Up) : 10 Frame : 09 Radiator Guard And Bonnet
| 01***16 | Bolt - Seat And Tether Belt Mounting | 4 |
| 01***20 | Bolt, Wiring Harness Mounting Bracket | 2 |
| 01***30 | Bolt,Stopper | 2 |
11 Drivers Cab
Komatsu : Wa80-5(S/N H50051-Up) : 11 Drivers Cab : 00 Safety Cabin
| 01***00 | Capscrew | 8 |
| 01***25 | Screw | 1 |
| 01***10 | Screw | 1 |
Komatsu : Wa80-5(S/N H50051-Up) : 11 Drivers Cab : 01 Safety Cabin, Doors
| 01***85 | Screw | 2 |
| 01***25 | Screw | 1 |
| 01***10 | Screw | 2 |
Komatsu : Wa80-5(S/N H50051-Up) : 11 Drivers Cab : 11 Soundproofing Of Cabin
| 42***53 | Plug | 4 |
| 42***63 | Ashtray | 1 |
| 42***66 | Washer | 4 |
Komatsu : Wa80-5(S/N H50051-Up) : 11 Drivers Cab : 17 Safety Cabin, Steering
| 42***58 | Screw | 2 |
| 42***66 | Washer | 6 |
| 42***75 | Disc | 4 |
Komatsu : Wa80-5(S/N H50051-Up) : 11 Drivers Cab : 18 Heater
| 42***60 | Plain Washer | 2 |
| 42***23 | Plain Washer | 6 |
| 42***59 | Gasket | 1 |
Komatsu : Wa80-5(S/N H50051-Up) : 11 Drivers Cab : 19 Air Conditioner
| 42***23 | Plain Washer | 6 |
| 42***23 | Nut | 4 |
| 42***26 | Screw | 6 |
Komatsu : Wa80-5(S/N H50051-Up) : 11 Drivers Cab : 27 Drivers Seat, Attaching Parts
| 01***25 | Screw | 4 |
| 01***25 | Washer,Spring?For Additional Rear Lam | 2 |
| 01***12 | Washer,(With Body Positioner) | 4 |
13 Hydraulic System
Komatsu : Wa80-5(S/N H50051-Up) : 13 Hydraulic System : 00 Pumps For Hydraulic System
| 42***01 | Shaft Seal | 1 |
| 42***02 | Circlip | 1 |
| 42***03 | Security Cap | 2 |
Komatsu : Wa80-5(S/N H50051-Up) : 13 Hydraulic System : 12 Control Valve
| 42***07 | Spool | 1 |
| 42***08 | Spool | 1 |
| 42***09 | Disc | 1 |
Komatsu : Wa80-5(S/N H50051-Up) : 13 Hydraulic System : 26 Lift Cylinder
| 01***20 | Bolt,(Forwarded Individually Parts) | 1 |
| 07***70 | O-Ring,(For Intake Air Cover) | 1 |
| 07***45 | O-Ring (K10) | 1 |
Komatsu : Wa80-5(S/N H50051-Up) : 13 Hydraulic System : 28 Bucket Cylinder
| 01***16 | Bolt - Starting Motor Ground Cable | 1 |
| 04***10 | Clamp | 1 |
| 07***90 | O-Ring,(Dk029369-0020) (K2) | 1 |
15 Equipment
Komatsu : Wa80-5(S/N H50051-Up) : 15 Equipment : 00 Bucket
| 42***80 | Bucket | 1 |
| 42***40 | Chopper | 1 |
| 42***70 | Reinforcement | 2 |
Komatsu : Wa80-5(S/N H50051-Up) : 15 Equipment : 02 Quick Change
| 42***30 | Change Device | 1 |
| 42***31 | Disc | 2 |
| 42***32 | Pin | 2 |
WA80-5(S/N H50051-UP) serial number reference
The serial/PIN plate on Komatsu wheel loaders of this era is mounted on the machine frame, typically near the operator's cab; exact side (left or right) varies by model and production plant, so check both sides if it is not immediately visible. Komatsu also stamps the number directly into the frame steel near the plate. Read it as a letter-plus-two-digit block code (here "H50") followed by the sequential unit number - e.g., H50051 is unit 051 in the H50 block. "And up" means every unit from that number forward, with no later internal break documented for this generation. Verify exact plate location and confirm no later serial break applies to a specific unit with your dealer.
| Prefix | Identifies | Notes |
|---|---|---|
| H50 | WA80-5, 20 km/h standard drivetrain | Base WA80-5 configuration, S/N H50051 and up, no upper limit documented for this run. Engine is the naturally aspirated Komatsu 4D95LE-3, mechanically governed, no turbo or intercooler, rated about 45 kW (60 HP) at 2,350 rpm. Full hydrostatic transmission, switchable in all directions under full power, with two speed ranges each way. Built roughly 2004-2008. Covered in the same wheel loader shop-manual family as the smaller WA65-5 and WA70-5; confirm with your dealer whether those models run their own independent serial sequence or share this same number block, since manual listings are not fully consistent on this point. |
| H50 | WA80-5, 30 km/h high-speed drivetrain (export/European-market gearing) | Same chassis serial break, S/N H50051 and up, built with alternate final-drive/transmission gearing for a higher top travel speed than the standard 20 km/h version. Shows up in export-market parts literature, including German-language listings, alongside the standard variant, both starting at the same number. Uses the same naturally aspirated 4D95LE-3 engine as the standard drivetrain; only the travel-speed gearing differs. Confirm with dealer which drivetrain a specific unit carries, since both configurations share the identical serial prefix and starting number. |
Frequently asked questions
What engine does the Komatsu WA80-5 (S/N H50051-UP) use?
It uses the Komatsu 4D95LE-3, a naturally aspirated, mechanically governed four-cylinder diesel of about 3.3 L displacement, rated near 45 kW (60 HP) at 2,350 rpm. There is no electronic engine control (ECM) on this engine.
What is the operating weight of the Komatsu WA80-5 (S/N H50051-UP)?
Operating weight runs about 5,640 kg (12,430 lb) in standard configuration and can reach roughly 5.9 t (13,000 lb) depending on bucket size, counterweight, and tire choice. Confirm the exact figure against your machine's spec plate and OMM capacity chart, since it varies by configuration.
What replaced the Komatsu WA80-5 (S/N H50051-UP)?
Komatsu replaced it with the WA80-6 starting around 2008. The WA80-6 moved to a turbocharged, higher-output variant of the same engine family with updated emissions and electronics, while keeping the same general compact articulated-loader layout.
What WA80-5(S/N H50051-UP) owners discuss
What kind of drivetrain does this loader use, and what do techs say about how it behaves day to day?
Any recurring complaints about the loader arm or bucket hydraulics?
What wear patterns show up on the frame, tires, and articulation joint?
What quirks or failure points come up with this engine?
What electrical or sensor problems come up?
What should I check before buying a used one?
Compiled from owner and technician discussions across the industry — experiences vary by serial range and machine history.
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