Home›Caterpillar›Caterpillar 3304

Caterpillar 3304 Generator Set

The Caterpillar 3304 is a 125 kW (125 kVA) diesel standby generator set powered by a Caterpillar 3304B engine. It is available at 220 V and 440 V, 3-phase and 60 Hz. It holds about 22 L (5.8 gal) of oil and 13 L (3.4 gal) of coolant. The set measures 1420.9×953×1141.3 mm (55.9×37.5×44.9 in) and weighs about 840 kg (1852 lb).

125 kW
Standby
7.0 L
Displacement
22.0 L
Oil capacity
5
Document types

How to read your Caterpillar serial & model number →

Typical fuel consumption for 125–130 kW Diesel generators →

Compare with other 125–130 kW Diesel generators →

Service parts for the 3304

Grouped by system, with how many of each the parts manual calls for.

Air intake

1 required

Fuel system

1 required
1R0750Fuel filter$21.82NAPA

Oil system

1 required

Belts

1 required

Hydraulic system

1 required
1R0741Hydraulic filter$22.00eBay

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

Specifications

Fueldiesel
Frequency60.0 Hz
Standby power125 kW
Standby kVA125
Prime power105 kW
Oil capacity22.0 L
Alternator24V 60 Amp Alternator
Voltage options220 V, 440 V
Phasethree-phase
Power factor0.8
Coolant capacity13 L
Dimensions (L×W×H)1420×953×1141 mm
Dry weight511 kg

Engine

Caterpillar 3304B
Oil capacity22.0 L
Coolant capacity32.0 L
Displacement7.0 L
AspirationNaturally Aspirated
Rated speed1800 rpm

Filters for the Caterpillar 3304B

6

Engine-mounted filters the filter manufacturers list for this engine family. These come from the engine, not from this generator set’s own parts list, so confirm against your serial number before ordering.

Listed for this engine in only one kind of machine, so they may depend on how the engine was installed:

SystemFilterDescriptionCross-references
Oil filterP551807Lube Filter, Spin-On Full FlowCATERPILLAR 1R0058, CATERPILLAR 1R1807, NAPA 1791, NAPA 7791 KuduParts $31.00
Oil filterP551808Lube Filter, Spin-On Full FlowCATERPILLAR 1R1808, CATERPILLAR 1R808, NAPA 7792, BALDWIN B7299 KuduParts $80.00
Fuel filterP550625Fuel Filter, Spin-On SecondaryCATERPILLAR 1165436, CATERPILLAR 1R0762, NAPA 3640, BALDWIN BF7753 buy
Fuel filterP551313Fuel Filter, Spin-On SecondaryCATERPILLAR 1R0763, BALDWIN BF7633, LOESING 025135, INGERSOLL RAND 1R0750 KuduParts $17.00
Fuel / water separatorP558000Fuel Filter, Water Separator Spin-On Twist&DrainCATERPILLAR 2266561, CATERPILLAR 3I1305, NAPA 3405, NAPA 3693 KuduParts $24.00 FridayParts $25.66
Fuel / water separatorP550316Fuel Filter, Water Separator CartridgeCATERPILLAR 3I1169, CATERPILLAR 8N205, NAPA 3401, BALDWIN PF316 FridayParts $48.12

Maintenance & consumables

for the Caterpillar 3304B
ItemSpecCapacityPart #Interval
Air filterAir filter housing1M7250 eBay $19.48 KuduParts $18.00 FridayParts $19.90
Fuel filterFilter fuel1R0750 Amazon eBay $33.80 eBay $33.80 NAPA $21.82 NAPA $21.82 KuduParts $17.00 FridayParts $29.50
Oil filterFilter oil1R0719 eBay $20.00 FridayParts $31.32 KuduParts $58.00
BeltV-belt7M4705 eBay $45.95 NAPA $48.82 FridayParts $82.99
Coolant32.0 L—
Hydraulic filterFilter hydraulic1R0741 eBay $22.00 NAPA $25.37
OilCaterpillar DEO 10W30 or 15W4022.0 L—500 hr

Service specifications

21
TypeItemValueUnitCondition
ClearanceCrankshaft end play.178 to .635mm (0.0070 to 0.0250 inch)measured with dial indicator
ClearanceCrankshaft end play after assembly0.178 to 0.635mm (0.0070 to 0.0250 inch)after assembly
ClearanceEnd play at heat sink after assembly0.076 to 0.635mm (0.0030 to 0.0250 inch)after assembly
ClearanceGap at 3, 6, 9, 12 o'clock positions0.03 to 0.13mm (0.001 to 0.005 inch)between
ClearanceGap between generator and flywheel housing at locations (E), (F), (G), (H)>0.03 and <0.13mm (0.001 inch to 0.005 inch)more than 0.03 mm and less than 0.13 mm
ClearanceGenerator forward offset from midpoint of end play+ 0.50mm (+ 0.0200 inch)while generator supported by crane
ClearanceRotor end play3.81 to 7.62mm (.150 to .300 inch)approximately
ClearanceShim thickness divisor for number of shims0.8mm (0.03 inch)divide Letter L by this value
ClearanceSupport deflection during bolt tightening0.13mm (0.005 inch)maximum allowed movement
TorqueBearing Nut Torque (129-3253 Spanner Socket, 121-9871 Bearing Nut)2375N·m
TorqueBearing Nut Torque (129-3254 Spanner Socket, 119-3711 Bearing Nut)2375N·m
TorqueBolts (10)100N-m (75 lb ft)Tighten in pairs at 180 degree intervals in three stages
TorqueBolts (7) for shim pack and plate assembly525 + 45N-m (390 + 30 lb ft)Tighten bolts (7)
TorqueCoupling plate assembly bolts (5)525 + 25N-m (390 + 20 lb ft)Tighten in 180 degree intervals in three stages
TorqueFan mounting bolts (11)200N-m (150 Ib ft)Tighten in pairs at 180 degree intervals in three stages
TorqueGenerator mounting bolts (half of standard torque)450N-m (332 lb ft)one half of standard torque
TorqueGenerator support bolts (half of final torque)450N-m (332 Ib ft)half of final torque
TorqueLocknut torque (260-0626 Spanner Socket Assembly, 1T-0229 High Torque Locknut)985N·m
TorqueSolenoid nut torque (FT3198 Solenoid Tool, 352-2733 solenoid)3.75Nm+/- .75
TorqueTightening torque for 369-5916 Lifting Eyebolt (M12 Hex Bit)115N·m
TorqueWorking torque capacity of locknut spanner wrenches (126-6608 / 126-6609)950N·m

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
CoolantCat DEACDiesel; 3,000 Service Hours or Three Years; annual S·O·SSM Level 2 coolant sampling and analysis
CoolantCat ELCDiesel; 12,000 Service Hours or Six Years; add Cat ELC Extender at 6,000 service hours or one half of service life; annual S·O·SSM Level 2 coolant sampling and analysis
CoolantCat NGECNatural Gas; 16,000 Service Hours or Three Years; use interval that occurs first
Engine oilCat NGEONatural Gas
Engine oilCat Arctic DEO SYN SAE 0W-30-40°C to 30°CEngine Crankcase; Industrial Engines
Engine oilCat DEO SYN SAE 5W-40-30°C to 50°CEngine Crankcase; Industrial Engines
Engine oilCat DEO SAE 10W-30-18°C to 40°CEngine Crankcase; Industrial Engines
Engine oilCat DEO SAE 15W-40-9°C to 50°CEngine Crankcase; Industrial Engines
GreaseCat Generator Set GreasePart Number 108-8611

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

Procedures

8
Alignment Of Electric Sets With Supports At The Flywheel Housing / Installation Of A New Generator Or Flexible Plates adjustment

Tools: crane, dial indicator, shims, torque wrench

  1. Loosen all bolts connecting base to foundation; loosen all bolts fastening engine supports and generator supports to base.
  2. Ensure enough clearance between bolts and bolt holes in base, engine supports, generator supports at all locations.
  3. Check clearance between base and foundation at all mounting locations; use shims to prevent deflection; tighten base-to-foundation bolts to final torque.
  4. While generator supported by crane, loosen all bolts (2) fastening generator to flywheel housing; tighten alternate bolts to final torque; check clearance between base and engine and generator support
  5. Tighten all bolts fastening engine supports and generator supports to base to half of final torque; loosen all bolts (2); measure gap between generator and flywheel housing; ensure bolts centered in c
  6. Gaps at (E), (F), (G), (H) should be more than 0.03 mm (0.001 inch) and less than 0.13 mm (0.005 inch); adjust shims or move rear of generator right or left.
  7. After shim correction, tighten generator support bolts to half of final torque 450 N-m (332 Ib ft); check gaps; repeat until 0.13 mm (0.005 inch) or less; begin with Step 5.
  8. Install dial indicator on base with tip next to support mounting bolt (4); put tip on support (3); check while tightening bolt to final torque; if indicator moves more than 0.13 mm (0.005 inch), insta
Alignment Of Electric Sets Without Supports At The Flywheel Housing adjustment

Tools: shims, torque wrench

  1. Loosen all bolts connecting base to foundation; loosen all bolts fastening generator supports and engine supports to base.
  2. Ensure clearance between bolts and bolt holes in base, engine supports, generator supports at all locations.
  3. Check clearance between base and foundation at all mounting locations; use shims to prevent base deflection; tighten base-to-foundation bolts to final torque.
  4. Check clearance between base and engine, base and engine supports, base and generator supports over entire length; use shims to prevent support deflection; tighten all mounting bolts to final torque.
Rechecking The Alignment adjustment

Tools: torque wrench, shims

  1. Loosen the sixteen close coupled adapter bolts (2); visually ensure they are centered in clearance holes.
  2. Check gaps at 3, 6, 9, and 12 o'clock positions; use 2, 4, 8, and 10 o'clock if 12 and 6 are inaccessible.
  3. If gaps are between 0.03 mm (0.001 inch) and 0.13 mm (0.005 inch), tighten all bolts; alignment check complete. If not, loosen bolts fastening generator to base frame; adjust shims; move rear of gener
  4. After adjustment, tighten generator mounting bolts to one half of standard torque 450 N-m (332 lb ft); repeat procedure starting with Step 1.
Installation Of The Generator For Generator Sets That Are Equipped With A 3500 Engine installation

⚠ Damage to engine and generator can result if electric set is operated with a plate assembly that does not have proper clearance.

⚠ If N or O is less than initial A, disassemble and check coupling plate for bowing; replace if bowed.

Tools: dial indicator, straight edge, magnetic bases, crane, torque wrench, 17 5N-4478 Plates

  1. Ensure generator is disengaged from engine; clean generator support and base contact surfaces; remove protective material from flywheel pilot bearing bore and coupling contact surface.
  2. Remove two engine side covers; rotate engine until no. 1 crankshaft throw is perpendicular; measure crankshaft end play with dial indicator; record as A and divide by two for B.
  3. With crankshaft at extreme forward position, measure distance from straight edge to flywheel housing mounting surface (C) and flywheel pilot surface (D); subtract D from C for E.
  4. Remove coupling bolts and washers; remove plates, shims, and exhaust fan; lift rotor; locate rotor so air gap equal; move rotor to extreme rear.
  5. Place dial indicator on vertical surface of heat sink at rear of rotor shaft; measure rotor end play (approximately 3.81 to 7.62 mm); record F and divide by two for G.
  6. Move rotor to extreme rear; position straight edge across mounting ring diameter; measure distance to mounting ring surface (H) and hub mounting surface (I); subtract H from I for J.
  7. Bolt a standard set of 17 5N-4478 Plates together; measure thickness in two locations along contour; average as K.
  8. Determine number of shims: subtract B, E, G, K from J for L; divide L by 0.8 mm (0.03 inch) for M; round up.
  9. Put coupling plate in flywheel bore; check clearance between coupling plate outside diameter and flywheel bore inside diameter.
  10. Install coupling plate assembly, bolts (6) and calculated shims; tighten bolts (5) in 180 degree intervals in three stages to 525 + 25 N-m (390 + 20 lb ft).
  11. Install guide bolts in flywheel; put generator on engine; install bolts (10); tighten to 100 N-m (75 lb ft) in pairs at 180 degree intervals in three stages.
  12. While crane supports generator, place dial indicator on heat sink vertical surface; push generator forward within + 0.50 mm (+ 0.0200 inch) of midpoint of end play.
  13. Install fan mounting bolts (11) into flywheel; tighten to 200 N-m (150 Ib ft) in pairs at 180 degree intervals in three stages.
  14. Place dial indicators on no. 1 crankshaft throw and heat sink; push crankshaft forward; check crankshaft end play 0.178 to 0.635 mm and heat sink end play 0.076 to 0.635 mm; record N and O.
  15. If N or O is less than initial A, disassemble; check coupling plate for bowing; replace if bowed; check calculations; install generator and repeat steps 13 and 15.
Installation Of The Generator For Generator Sets That Are Not Equipped With A 3500 Engine installation

⚠ Damage to engine and generator can result if electric set is operated with a plate assembly that does not have proper clearance.

Tools: dial indicator, indicator assembly, bar, torque wrench, guide bolt, crane

  1. Remove dirt, burrs, paint from generator support and base contact surfaces; remove protective material from flywheel pilot bearing bore and coupling contact surface.
  2. Remove timing pointer cover; install indicator assembly on front of engine; tip contacts crankshaft pulley face.
  3. Position plate assembly in flywheel bore; check clearance between plate outside diameter and bore inside diameter.
  4. Install full shim pack and plate assembly on generator with bolts; tighten bolts to 525 + 45 N-m (390 + 30 lb ft).
  5. Install guide bolt in flywheel; put generator on engine; install bolts (9) and (10); tighten but do not bend locks under bolts (8).
  6. Use dial indicator to check crankshaft end play; if reading differs from initial, remove generator and enough shims to get original end play.
  7. Install generator again and check crankshaft end play; after correct shims, bend locks under bolts (8).
Installation of two-piece seal into slack adjuster piston (209-6381 Seal Installer Group) maintenance

Tools: 207-3440 Loading Mandrel, 207-3442 Ring Pusher, 207-3444 Seal Sizer, 8F-8178 Bolt

  1. Place 207-3440 Loading Mandrel over small piston.
  2. Place inner portion of two-piece seal onto mandrel and push onto piston using 207-3442 Ring Pusher. Repeat for outer portion of seal.
  3. With both sets of seals installed, push piston assembly into 207-3444 Seal Sizer.
  4. Allow seals to compress for one minute and then install small piston into large piston.
Sprocket wheel removal - 8T-5243 Adapter Group installation maintenance

Tools: 8T-5243 Adapter Group, 7B-2499 Ring, 6H-4158 Pin, 5F-9306 Arm, 8S-9975 Ram Adapter, 9S-8900 Cylinder Group

  1. Install adapter groups evenly spaced in the holes in the sprocket flange; install the hooked adapter (1) first, then the plate (2).
  2. Fasten plate to adapter with two bolts (3) and washers (4); plate retains adapter in sprocket wheel.
  3. Before installing remainder of tooling, loosen bolt (5) to leave about 6.35 mm (0.25 in) gap between retainer (6) and sprocket wheel.
  4. Install the hydraulic cylinder and the remainder of the tooling in the conventional manner.
STOR Plug Assembly application for disc brake piston retainer spring (174-5354) repair

Tools: 174-5354 STOR Plug Assembly, 134-2562 Guides, 9S-9334 Plugs, 6N-9155 Pin

  1. Insert four 134-2562 Guides and discontinued 130-8718 Springs as an assembly into brake group anchor exterior holes where 9S-9334 Plugs are normally located.
  2. Insert four 174-5354 Plug Assemblies into exterior holes and finger tighten.
  3. Screw in attached bolts until guide noses protrude through brake piston.
  4. Insert discontinued 6N-9155 Pin into each guide hole and remove bolts and plugs.
  5. Insert four 9S-9334 Plugs into vacated holes.

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

Common questions

How many kW is the Caterpillar 3304?

The Caterpillar 3304 is rated 125 kW standby (125.0 kVA).

What engine is in the Caterpillar 3304?

The Caterpillar 3304 is powered by the Caterpillar 3304B engine.

What fuel does the Caterpillar 3304 use?

The Caterpillar 3304 runs on diesel.

What's the oil capacity on a Caterpillar 3304?

The Caterpillar 3304B engine in the Caterpillar 3304 has an oil capacity of 22.0 liters.

What is the coolant capacity of the Caterpillar 3304?

The Caterpillar 3304 cooling system holds 13 liters (3.4 US gallons) for the radiator system including the engine, per the manufacturer specification sheet.

What is the prime power rating of the Caterpillar 3304?

The Caterpillar 3304 is rated 105 kW prime (113 kVA), against 125 kW standby.

What is the dry weight of the Caterpillar 3304?

The Caterpillar 3304 has a dry weight of 511 kg (1126 lb).

What voltages is the Caterpillar 3304 available in?

The Caterpillar 3304 is offered in 220 V, 440 V, three-phase-phase.

What alternator comes on the Caterpillar 3304?

The Caterpillar 3304 uses a 24V 60 Amp Alternator alternator.

What oil filter does the Caterpillar 3304 use?

The Caterpillar 3304 uses oil filter part number 1R0719.

What fuel filter fits the Caterpillar 3304?

The Caterpillar 3304 uses fuel filter part number 1R0750.

Which air filter part number does the Caterpillar 3304 take?

The Caterpillar 3304 uses air filter part number 1M7250.

Parts

32
Part #DescriptionQtySystem
102-2828Filter oil1Oil filter eBay $15.00
111-8010ThermostatThermostat eBay $44.99 FridayParts $18.60
151-2409Filter water separator1Fuel filter Amazon eBay $14.95 FridayParts $40.99
172-7766Water pump1Pump eBay $412.44 FridayParts $205.99
1M7250Air filter housingAir filter eBay $19.48 KuduParts $18.00 FridayParts $19.90
1R-1740Standard Efficiency Fuel Filter1Filter Amazon eBay $21.00
1R0719Filter oilOil filter eBay $20.00 FridayParts $31.32 KuduParts $58.00
1R0741Filter hydraulicHydraulic filter eBay $22.00 NAPA $25.37
1R0750Filter fuelFuel filter Amazon eBay $33.80 eBay $33.80 NAPA $21.82 NAPA $21.82 KuduParts $17.00 FridayParts $29.50
1W1695Lift/transfer pumpPump eBay $779.96 FridayParts $56.00
3E2026SwitchSensor eBay $69.00 FridayParts $42.99
3S3875Filter fuelFuel filter eBay $49.99
3T9561Glow plugGlow plug eBay $20.50
3T9562Glow plugGlow plug eBay $9.50 SinoCMP $29.00 FridayParts $37.07
4N8969TurbochargerTurbocharger eBay $381.35 FridayParts $349.05 SinoCMP $449.00
4W3864Water pump sealSeal eBay $9.27
6I1346Oil pumpPump eBay $178.00 FridayParts $251.83 SinoCMP $309.00
7M4705V-beltBelt eBay $45.95 NAPA $48.82 FridayParts $82.99
7N5910Water pump impellerImpeller eBay $48.00
8N0205Filter water separatorFuel filter eBay $60.00 NAPA $79.10 FridayParts $35.00
8N9803Filter water separatorFuel filter eBay $33.99 KuduParts $43.00 FridayParts $45.65
9M9740Filter oilOil filter eBay $22.99 FridayParts $31.32 KuduParts $58.00
9N3717Filter water separatorFuel filter eBay $42.00
9T0973Filter hydraulic/transmissionHydraulic filter eBay $92.60 NAPA $151.86 KuduParts $75.00 FridayParts $77.02
9Y1979Gasket exhaust manifoldGasket eBay $5.00
DM-6J6915SEAL RING 3304Seal Amazon eBay
ESD5500ESpeed ControllerSpeed controller Amazon eBay FridayParts $50.53
M-1W3711Alternator, V, .69in (17.5mm) - 67.99in (1727mm)2Belt Amazon eBay
8N1721Connecting rodService part / kit Amazon eBay $96.99 FridayParts $113.40
8N1984Connecting rodService part / kit Amazon eBay $275.00 FridayParts $114.19
PEHP3036Cat Reman Short and Long BlocksService part / kit Amazon eBay
PEHP3036-01Cat Reman Short and Long BlocksService part / kit Amazon eBay

Service, wear & replacement parts referenced for this model and its engine — confirm the exact part for your serial number. See the full parts catalog to search and cross-reference.

Fuel consumption

RatingLoadL/hgal/h
Prime23%10.82.9
Prime29%11.93.1
Prime48%16.94.5
Prime53%19.05.0
Prime74%25.06.6
Prime76%25.16.6
Prime94%35.89.5
Prime100%22.716.0
Standby23%10.82.9
Standby53%19.05.0
Standby74%25.06.6
Standby94%35.89.5

Available documents

Engine spec — LEHM1536-00 (Caterpillar)Engine spec — LEHM1537-00 (Caterpillar)Engine spec — LEHM1588-00 (Caterpillar)Engine spec — LEHM1591-00 (Caterpillar)Engine spec — Spec Sheets - Cat 3304B DINA Auxiliary (Caterpillar)Engine spec — cat-3304-marine-spec-sheet-abby (Caterpillar)Engine spec — lfhh5447 (Caterpillar)Engine spec — lfhh5448 (Caterpillar)Engine spec — lfhh6261 (Caterpillar)Engine spec — lghh5447 (Caterpillar)Engine spec — lshh5447 (Caterpillar)Engine spec — lshh6258 (Caterpillar)Engine spec — lshh6261 (Caterpillar)Spec sheet — LEHM1230 (Caterpillar)Spec sheet — LEHM1231 (Caterpillar)Spec sheet — LEHM1534-00 (Caterpillar)Spec sheet — LEHM1535-00 (Caterpillar)Spec sheet — Spec Sheet - Cat 3304B DIT Genset (Caterpillar)Spec sheet — Spec Sheets - Cat 3304B DINA Genset (Caterpillar)Spec sheet — cat-3304b-dit-genset (Caterpillar)Reference (Caterpillar)Reference — LECW2462-01 (Caterpillar)Parts manual — 04-Power Train Tools (Caterpillar)Parts manual — Caterpillar Engines (Caterpillar)Parts manual — KMP-Brand®Parts-Guide-Suitable-for-Caterpillar®By-Product (Caterpillar)Service manual — Alignment of Single Bearing Generators (Caterpillar)

This page was generated from the 26 manufacturer documents above by automated extraction; every figure shown is copied from one of them. How the data is compiled.

Full service, cheapest listings

Priced items from this model's own parts manual.

Air filter 1M7250$19.48
Fuel filter 1R0750$21.82
Oil filter 1R0719$20.00
Belt 7M4705$45.95
Hydraulic filter 1R0741$22.00
5 priced items$129.25