Perkins 4012 Parts List: Genuine OEM Part Numbers for the 4012-46TAG Generator Engine

The Perkins 4012 is the V12 member of the Perkins 4000 Series, with a total displacement of 45.8 liters and generator outputs from 1,000 kVA to 1,600 kVA. In the 4012-46TAG generator specification—the most widely deployed variant—the engine provides approximately 1,290 kVA prime / 1,420 kVA standby at 1,500 rpm (50 Hz), powering critical applications in data centers, hospitals, airports, semiconductor fabs, and large commercial complexes. The 4012 shares its cylinder architecture with the 4008 (V8) and 4016 (V16), all built at Perkins’ Stafford, UK plant, which gives the series exceptional parts commonality for service items while keeping internal components model-specific.

This Perkins 4012 parts list is a practical reference for service engineers and B2B parts procurement teams. It covers the genuine OEM part numbers most commonly ordered for the 4012-46TAG and related 4012-46TRS / 4012-46TAG2 builds, organized by system. Always confirm your engine serial number against the latest Perkins electronic parts catalog before ordering—the 4012 has documented serial-number breaks affecting injector calibration, turbo trim, and ECM software levels.

Perkins 4012 Engine Overview and Key Specifications

The 4012 is a four-stroke, turbocharged and aftercooled V12 diesel with a 60-degree bank angle, one-piece cast iron block, wet cylinder liners, and a forged steel crankshaft running in eight main bearings. The generator-spec engine is governed at 1,500 rpm (50 Hz) or 1,800 rpm (60 Hz), with B100 biodiesel capability in later variants. Cooling is provided by a jacket water circuit plus charge-air aftercooler; radiator packages and heat exchanger packages are both common in genset installations.

Perkins 4012 Parts List: Fuel System Components

The 4012 fuel system uses the same two-stage filtration architecture as the rest of the 4000 Series: a primary water-separating filter and a secondary 4-micron filter feeding twelve unit injectors. Fuel flow rates are high—around 95 L/h at full load—so filter element quality directly affects injector life.

4012 Fuel Filters and Fuel Delivery

• Primary Fuel Filter / Water Separator — Perkins P/N 26510318: Shared with the entire 4000 Series. Service interval: 500 hours or annually. The 4012’s large fuel flow makes water contamination particularly damaging—a single bad fuel delivery can take out all twelve injectors.
• Secondary Fuel Filter (4 micron) — Perkins P/N 26510319: Final filtration ahead of the injectors. Use genuine elements only; the 4-micron rating is a hard requirement for unit injector reliability.
• Fuel Filter Base Gasket — Perkins P/N 26510321: Replace with every element service to prevent air ingress.
• Fuel Lift Pump (gear type) — Perkins P/N 26510122: The 4012 uses a higher-capacity gear pump than the 4008. Symptoms of wear: low rail pressure, poor cold starting, and fuel starvation at load.
• Fuel Injector (unit injector) — Perkins P/N 26545702: Twelve required. Genuine injectors are supplied as calibrated sets; replace all twelve together to maintain cylinder balance. Typical life in clean-fuel duty: 12,000-15,000 hours.
• Injector Hold-Down Clamp — Perkins P/N 26545707: Inspect threads at every injector service.
• High-Pressure Fuel Line (per cylinder) — Perkins P/N 26545713: Braided steel; inspect for chafing and replace at the first sign of surface cracks.

Related guide: Perkins Fuel Filter Guide covers service intervals across the whole range, and Generator Fuel Injector Troubleshooting Guide explains injector failure diagnosis in detail.

Perkins 4012 Parts List: Lubrication System

Lubrication on the 4012 is a full-flow pressure system with a duplex filter head and an oil cooler. Oil capacity is approximately 136 liters (35.9 US gallons) including filters—roughly 1.5 times the 4008’s capacity, reflecting the larger sump and oil gallery volume.

4012 Oil Filters and Pump

• Oil Filter (element, duplex) — Perkins P/N 26510343: Two elements per service, shared with all 4000 Series engines. Change at 500 hours (prime) or annually (standby).
• Oil Pump — Perkins P/N 26510106: The 4012 oil pump is a larger-displacement gear pump than the 4008 unit. Minimum oil pressure at low idle: 1.0 bar (14.5 psi); sustained pressure below spec with good oil level indicates pump or bearing wear.
• Oil Cooler Core — Perkins P/N 26510153: If oil temperature exceeds 105°C, test the oil cooler before condemning the pump.
• Oil Pressure Sensor — Perkins P/N 26510178: Feeds the ECM; a faulty sensor causes false low-oil-pressure shutdowns—a serious nuisance on standby sets that self-test unattended.

Oil specification: SAE 15W-40 API CI-4/CJ-4 above -10°C; 10W-30 or 5W-40 below. The 4012’s oil consumption target is 0.1-0.3% of fuel consumption; higher consumption with blue smoke at idle indicates ring or valve guide wear.

Perkins 4012 Parts List: Cooling System

Generator-spec 4012 engines reject substantial heat—at 1,400 kVA the cooling system must dissipate roughly 500 kW of engine heat. The standard arrangement includes a jacket water pump, a raw water pump (heat exchanger sets), and a charge-air aftercooler circuit.

4012 Water Pumps, Thermostats and Coolant Parts

• Jacket Water Pump — Perkins P/N 26510115: Shared with the 4008/4016 (front-mounted centrifugal pump). Service at 6,000 hours or on bearing/weep signs.
• Raw Water Pump — Perkins P/N 26510117: Larger bronze pump for the V12’s higher heat rejection.
• Thermostat (82°C, dual housing) — Perkins P/N 26510199: The 4012 uses two thermostats in a dual housing to manage the higher coolant flow. Always replace both together.
• Coolant Hoses (upper/lower) — Perkins P/N 26510223 / 26510224: Replace at 4,000-hour intervals.
• Radiator Cap (15 psi) — Perkins P/N 26510244: Shared across the 4000 Series.
• Aftercooler Core — Perkins P/N 26510191: The V12 aftercooler is a larger core than the 4008 unit; a leak causes unexplained coolant consumption under boost.

Use Perkins-specified ELC coolant (50/50 OAT mix). Do not mix coolant chemistries—silicate dropout is a common cause of water pump seal failure on 4000 Series engines.

Perkins 4012 Parts List: Turbocharger and Air System

The 4012 is twin-turbocharged—one turbo per cylinder bank—with a combined air flow approaching 9 m³/min at rated power. The air system is the highest-cost subsystem after the engine block itself, so preventive maintenance here has outsized financial value.

4012 Turbochargers and Air Intake

• Turbocharger (complete, each bank) — Perkins P/N 26510141: Two required. The 4012 turbo is the same family as the 4008 unit but with bank-specific housings and trim. Replace in pairs where possible to keep boost balanced between banks.
• Turbo Rebuild Kit — Perkins P/N 26510142: Journal bearings, thrust washer, and seals per turbo.
• Air Filter Element (primary) — Perkins P/N 26510330: Radial-seal element shared across the 4000 Series. Replace at 1,000-2,000 hours or on restriction indicator.
• Air Filter Element (safety) — Perkins P/N 26510331: Replace every third primary change.
• Charge-Air Hose Set — Perkins P/N 26510196: Silicone hoses between turbo outlets, aftercooler, and inlet manifold; inspect for delamination and leaks annually—boost leaks on a twin-turbo V12 cause significant power loss and black smoke.

For turbocharger sourcing across brands, see Generator Spare Parts Supplier and the Cummins KTA50 Parts List for comparison with a competitive large V16.

Perkins 4012 Parts List: Engine Overhaul Components

The 4012 overhaul window is typically 20,000-25,000 hours for prime power. The genuine parts list below covers the full in-frame rebuild scope for the 4012-46TAG.

4012 Pistons, Liners, Bearings, Valves and Rotating Assembly

• Cylinder Liner (wet, complete) — Perkins P/N 26510360: Shared liner with the 4008/4016; twelve required on the 4012.
• Piston Assembly — Perkins P/N 26510364: The 4012 piston is a high-silicon aluminum forging with steel ring carrier, matched to the V12’s higher BMEP. Twelve required.
• Piston Ring Set — Perkins P/N 26510368: 2 compression + 1 oil control per piston.
• Main Bearing Set — Perkins P/N 26510147: Eight main bearings; grade selection by journal measurement.
• Big End Bearing Set — Perkins P/N 26510148: Twelve connecting rod bearings; check rod grade markings.
• Connecting Rod Assembly — Perkins P/N 26510149: Replace if the big-end bore is out of round; never re-machine.
• Intake Valve — Perkins P/N 26510150 / Exhaust Valve — Perkins P/N 26510151: 24 valves total; shared valve family with the 4000 Series.
• Cylinder Head Gasket — Perkins P/N 26510387: MLS gasket, one per bank side (12-cylinder heads total on a V12 with individual heads per cylinder).
• Crankshaft (complete) — Perkins P/N 26510137: Forged steel, 8 main journals, regrindable to 0.25/0.50 mm undersize.
• Camshaft (each bank) — Perkins P/N 26510139: Two camshafts on the V12; replace lobes worn beyond 0.05 mm.

B2B tip: order an in-frame overhaul kit (liners, pistons, rings, bearings, gaskets, seals) for the 4012 to benefit from matched-batch components and kit pricing—typically 15-25% below piecemeal ordering.

Perkins 4012 Parts List: Gaskets, Seals and Electrical Components

4012 Gasket Kits and Engine Seals

• Top Overhaul Gasket Kit — Perkins P/N 26510392: Head gaskets, valve stem seals, manifold gaskets, injector washers.
• Bottom Overhaul Gasket Kit — Perkins P/N 26510393: Oil pan, front/rear crankshaft seals, cam cover and water pump gaskets.
• Front Crankshaft Oil Seal — Perkins P/N 26510161 / Rear — Perkins P/N 26510162: Replace both at overhaul; the 4012 rear seal change requires flywheel and coupling removal.
• Valve Stem Seal — Perkins P/N 26510163: Set of 24.

4012 Electrical and Control Parts

• Starter Motor — Perkins P/N 26510181: 24V high-torque starter; the 4012’s compression ratio demands a healthy starter—slow cranking with good battery voltage means starter or cabling issues.
• Engine Charging Alternator — Perkins P/N 26510186: 24V/100A unit for the higher electrical load of a large standby set.
• Crankshaft Speed Sensor — Perkins P/N 26510192: Shared with the 4000 Series; failure prevents start.
• Coolant Temperature Sensor — Perkins P/N 26510193: Shared; replace on spurious high-temp alarms.
• Oil Pressure Sensor — Perkins P/N 26510178: Shared with 4012 ECM monitoring.
• Glow Plug — Perkins P/N 26510194: Twelve units for cold-start aid.

Perkins 4012 Parts Interchangeability with 4008 and 4016

Service parts commonality across the 4000 Series is one of the strongest arguments for standardizing a fleet on Perkins 4000 engines. The following are shared across 4006/4008/4012/4016: fuel filters (26510318/26510319), oil filter (26510343), air filter elements (26510330/26510331), jacket water pump (26510115), thermostat (26510199), crankshaft seals (26510161/26510162), speed sensor (26510192), coolant temperature sensor (26510193), and glow plugs (26510194). This allows a single inventory line to support an entire fleet.

Model-specific parts on the 4012 include the crankshaft (longer throw and additional main bearing journal vs the 4008), pistons (26510364), connecting rods (26510149), camshafts (26510139), oil pump (26510106), injectors (26545702), and turbochargers (26510141). Do not attempt to fit 4008 pistons or rods into a 4012—the V12’s higher cylinder pressures demand the heavier-duty components. For genuine verification and sourcing strategy, see our Perkins Generator Spare Parts Guide and Perkins Parts Supplier China guides.

How to Order Perkins 4012 Parts for B2B Buyers

Volume buyers of 4012 parts should prepare the following for every order to avoid specification mismatches:

1. Full engine serial number—required for parts book lookup; the 4012 has multiple serial-number breaks affecting injector and turbo trim.
2. Genset builder and rating—accessories such as radiators, air cleaners, and control wiring differ by package.
3. Frequency and duty—50/60 Hz and prime/standby rating affect governor, turbo, and cooling choices.
4. Kit or piece-part preference—filters by the case, gasket kits by the set, overhaul kits for planned rebuilds.
5. Export documentation—OEM Certificate of Origin, commercial invoice, packing list for customs.

Related fleet-planning resources: Perkins 4008 Parts List, Perkins 4016 Parts List, and the Generator Spare Parts Inventory Management Guide.

Frequently Asked Questions