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Home›Engines›Caterpillar C6.6 ACERT

Caterpillar C6.6 ACERT Engine

The Caterpillar C6.6 ACERT is a 6.6 L 6-cylinder ta engine rated at 1800 rpm, producing up to 168 kW. It powers generator sets from Caterpillar, including the D125, D150 and D175. It holds 11.5 L (3.0 gal) of oil and 15.5 L (4.1 gal) of coolant.

Also known as: Caterpillar C6.6 ACERT

Part of the Caterpillar C6.6 engine family — 6 variants share parts & fitment.

6.6 L
Displacement
6
Cylinders
1800 rpm
Rated speed
168 kW
Gross power
On this pageService partsSpecsGenerator setsMaintenanceFilter cross-referenceFAQService intervalsTorque & specsFluidsProcedures

Service parts for the C6.6 ACERT

The cheapest captured merchant offer per filter — see the full cross-reference below for every OEM/aftermarket option.

Air intake

1 required
2525001Air filterfind

Fuel system

2 required
1165436Fuel filter$36.00eBay
1466695Fuel filter (primary)$35.86eBay

Oil system

1 required
4621171Oil filter$33.99eBay

Prices captured from merchant listings; some links are affiliate links. Verify against your serial number before ordering.

Engine specifications

Oil capacity11.5 L
Coolant capacity15.5 L
Displacement6.6 L
Cylinders6
AspirationTA
Rated speed1800 rpm
Gross power168 kW

Maintenance schedule

ItemSpecCapacityPart #Interval
Air filterAir filter with monitoring system—
Fuel filterCat high efficiency fuel filters with Stay-Clean Valve, primary and secondary filters in engine compartment1466695 Amazon eBay $35.86 FridayParts $33.99
Oil filterCaterpillar air filter for engine compartment—
Battery—
Belt—
CoolantExtended Life Coolant or conventional heavy-duty coolant—
Spark plug—

Pooled from every document that names this exact engine — confirm the interval and part number against your unit's serial number.

Service intervals

1
ItemActionHoursMonthsNotes
Engine oil filterReplace512 hrLast changed 6/10/24, 512HRS

Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.

Service specifications

1
TypeItemValueUnitCondition
VoltageDC Voltage13.8Vload bank test, all stages

Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.

Recommended fluids

FluidGradeStandardAmbientCapacityNotes
FuelLCV = 42700 kJ/kgMaK technical data; without engine-driven pumps, tolerance 5%
Fuel35° API gravity at 60°F (16°C)LHV 18,390 Btu/lb (42 780 kJ/kg)Fuel at 85°F (29°C) weighing 7.001 lbs/U.S. gal (838.9 g/liter)
FuelEPA 2D 89.330-96Density 0.845 – 0.850 kg/L (7.052 – 7.094 lbs/U.S. gal.) @ 15°C (59°F); fuel inlet temperature 40°C (104°F); fuel rates based on this specification

Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.

Procedures

1
Load Bank Test diagnostic

Tools: Load bank

  1. Warm up
  2. Start and record no-load readings
  3. Apply load and record readings at 15 min
  4. Record readings at 30 min
  5. Record readings at 45 min
  6. Record readings at 1 hour
  7. Cool down and record readings

Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.

Parts cataloged across the Caterpillar C6.6 family

18
Part #DescriptionCategory
S200-0369Maintenance-free battery, 1000 CCA (2)Battery
S200-0632Starting and charging system, 24VBattery
S200-1156Keyless battery disconnect switchBattery
S200-0863Keyless ignition stop/start switchIgnition
S200-1038Starting aid, thermalIgnition
S200-0578Directional signals, front & rearLight
S200-0758Halogen work lights, front & rearLight
S200-0957Roading lightsLight
289-26305×5 fl ood, work lampsLighting
389024500-CCoolant heater, 1500W, 120VService part / kit
AEHQ5826-01Replaces AEHQ5826-01Service part / kit
AEHQ5982-01RService part / kit
INT9-101FReplaces any core plugService part / kit
INT9-102FReplaces any core plugService part / kit
NRG22-10-RCBattery charger, 120/208-240V, 6/3AService part / kit
PA50Winch Model PA50Service part / kit
TPL-489-COPERATING & MAINTENANCE OF D175Service part / kit
JPR-HDS170PUMP ASSYPump

Parts cataloged across all variants of this engine family — verify the exact part fits your specific variant and serial number before ordering.

Filters for this engine

  • Air filter: Caterpillar 2525001 Caterpillar 2525002 Caterpillar 1282686 Caterpillar 6I2502 Caterpillar 2567902 Caterpillar 2567903 Donaldson P635904 Donaldson P635980
  • Fuel filter: Caterpillar 1165436 Caterpillar 1466695 Donaldson P550625 Donaldson P553205 Wix 33640 Baldwin BF7753 Wix 33675 Baldwin BF1350-SP
  • Fuel filter (primary): Caterpillar 1466695 Donaldson P553205 Wix 33675 Baldwin BF1350-SP
  • Oil filter: Caterpillar 4621171 Caterpillar IR1807 Caterpillar 3890434 Donaldson P550920 Donaldson P551807 Donaldson P551808 Wix 57325 Baldwin B7378

Cross-referenced via Donaldson + OEM/engine-maker interchange — options to verify against your serial number, not confirmed for every exact variant.

Also used in

12
  • Caterpillar 928H — Loader Wheeled
  • Caterpillar 953D — Loader Tracked
  • Caterpillar 963D — Loader Tracked
  • Caterpillar CP56 — Compactor
  • Caterpillar CP64 — Compactor
  • Caterpillar CP74 — Compactor
  • Caterpillar D6N LGP — Tractor Tracked
  • Caterpillar D6N XL — Tractor Tracked
  • Claas LEXION 510 — Combine
  • Claas LEXION 520 — Combine
  • Claas LEXION 520 MONTANA — Combine
  • Claas LEXION 540C — Combine

Other equipment known to use this engine, via filter-application cross-reference — useful for sourcing parts even when your exact machine isn't listed elsewhere on this page.

Common questions

What is the oil capacity of the Caterpillar C6.6 ACERT?

The Caterpillar C6.6 ACERT engine has an oil capacity of 11.5 liters.

What is the displacement of the Caterpillar C6.6 ACERT?

The Caterpillar C6.6 ACERT has a displacement of 6.6 liters with 6 cylinders.

Which generators use the Caterpillar C6.6 ACERT engine?

The Caterpillar C6.6 ACERT powers 3 generator set(s), including Caterpillar D125, Caterpillar D150, Caterpillar D175.

What oil filter does the Caterpillar C6.6 ACERT use?

The Caterpillar C6.6 ACERT uses oil filter part numbers Caterpillar 4621171, Caterpillar IR1807, Caterpillar 3890434.

What fuel filter does the Caterpillar C6.6 ACERT use?

The Caterpillar C6.6 ACERT uses fuel filter part numbers Caterpillar 1165436, Caterpillar 1466695, Donaldson P550625.

What air filter does the Caterpillar C6.6 ACERT use?

The Caterpillar C6.6 ACERT uses air filter part numbers Caterpillar 2525001, Caterpillar 2525002, Caterpillar 1282686.