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Cummins/Onan DYH 250 kW Generator Set

The Cummins/Onan DYH 250 kW is a 250 kW Diesel standby generator set powered by a Allis-Chalmers 21000 MKII engine. It is available at 120/208 V, 127/220 V, 139/240 V, 240/416 V, 254/440 V and 277/480 V, 3-phase, 60 Hz and rated 868 A. It holds about 11.25 L (3.0 gal) of oil and 16.5 L (4.4 gal) of coolant, with a maximum ambient rating of -4 °C. Starting uses 2 group-8 batteries rated 225 CCA at 24 V. The set measures 1851×1778×950 mm (72.9×70.0×37.4 in) and weighs about 72.88 kg (161 lb). An integrated tank holds 15 L (4.0 gal), roughly 10.5 hours of runtime.

250 kW
Standby
13.8 L
Displacement
11.25 L
Oil capacity
1
Document types

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Specifications

FuelDiesel
Frequency60.0 Hz
Standby power250 kW
Prime power208 kW
ControllerVoltage Regulator
Oil capacity11.25 L
AlternatorYB 17
Voltage options120/208 V, 127/220 V, 139/240 V, 240/416 V, 254/440 V, 277/480 V
Phase3
Rated current868 A
Power factor0.8
Circuit breaker868 A
Battery group8D
Battery cranking225 CCA
Battery voltage24 V
Battery quantity2
Coolant capacity16.5 L
Max ambient-4 °C
Dimensions (L×W×H)1851×1778×950 mm
Dry weight72 kg
Fuel tank15.0 L
Tank runtime10.5 hr

Engine

Allis-Chalmers 21000 MKII
Oil capacity11.25 L
Coolant capacity16.5 L
Displacement13.8 L
AspirationNatural
Rated speed1800 rpm

Filters for the Allis-Chalmers 21000 MKII

4

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.

SystemFilterDescriptionCross-references
Oil filterP550132Lube Filter, CartridgeALLIS-CHALMERS 00185691, ALLIS-CHALMERS 00188056, NAPA 1133, RENAULT VI 0003180836 buy
Oil filterP550493Lube Filter, CartridgeALLIS-CHALMERS 11955, ALLIS-CHALMERS 61814, NAPA 1554, MERCEDES-BENZ 0021840525 buy
Fuel filterP550522Fuel Filter, CartridgeALLIS-CHALMERS 0027040, ALLIS-CHALMERS 0227040, NAPA 3073, BALDWIN PF916 Amazon eBay
Coolant filterP554071Coolant Filter, Spin-OnALLIS-CHALMERS 04734562, ALLIS-CHALMERS 40200892, NAPA 4071, WALGAHN-MOTORENTECHN 00811412 FridayParts $397.60

Common questions

What is the power rating of the Cummins/Onan DYH 250 kW?

The Cummins/Onan DYH 250 kW is rated 250 kW standby.

What engine does the Cummins/Onan DYH 250 kW use?

The Cummins/Onan DYH 250 kW is powered by the Allis-Chalmers 21000 MKII engine.

Is the Cummins/Onan DYH 250 kW diesel or gas?

The Cummins/Onan DYH 250 kW runs on Diesel.

How much oil does the Cummins/Onan DYH 250 kW take?

The Allis-Chalmers 21000 MKII engine in the Cummins/Onan DYH 250 kW has an oil capacity of 11.25 liters.

How much coolant does the Cummins/Onan DYH 250 kW hold?

The Cummins/Onan DYH 250 kW cooling system holds 16.5 liters (4.4 US gallons) for the radiator system including the engine, per the manufacturer specification sheet.

What is the continuous rating of the Cummins/Onan DYH 250 kW?

The Cummins/Onan DYH 250 kW is rated 208 kW prime, against 250 kW standby.

How much does the Cummins/Onan DYH 250 kW weigh?

The Cummins/Onan DYH 250 kW has a dry weight of 72 kg (160 lb).

How big is the fuel tank on the Cummins/Onan DYH 250 kW?

The Cummins/Onan DYH 250 kW has a 15 liter (4 US gallon) fuel tank, giving about 10.5 hours of runtime.

What voltage does the Cummins/Onan DYH 250 kW produce?

The Cummins/Onan DYH 250 kW is offered in 120/208 V, 127/220 V, 139/240 V, 240/416 V, 254/440 V, 277/480 V, 3-phase.

What size battery does the Cummins/Onan DYH 250 kW need?

The Cummins/Onan DYH 250 kW uses 2 batteryies, 24 V each, 225 CCA, group 8D, per the manufacturer specification sheet.

What alternator comes on the Cummins/Onan DYH 250 kW?

The Cummins/Onan DYH 250 kW uses a YB 17 alternator.

Troubleshooting

6

Symptoms & remedies

SymptomRemedy
Overcrank fault lamp lights and engine stops cranking after approximately 75-seconds.See engine service manual for troubleshooting fuel system. After correcting fault, reset engine monitor relay by placing Run-Stop/Reset-Remote switch to Stop/Reset position, depressing Reset button, then to the required running position.
Engine runs, shuts down, cranks for 75-seconds, cranking cycle stops, overcrank light ON.1. See engine service manual for troubleshooting fuel system. After correcting fault, reset engine monitor relay by placing Run-Stop/Reset-Remote switch to Stop/Reset position, depressing Reset button, then to the required running position. 2. Check fuel supply.
Low oil pressure shutdown.3. Check — a. Oil level. Replenish if necessary. b. Sensor. Faulty sensor will shut down engine. c. Refer to engine service manual for troubleshooting guide for oil system.
High engine temperature shutdown.4. Check — a. Coolant level. Replenish if necessary. b. City water cooled sets. Check water flow, valves, etc. c. Check sensor; check thermostat. d. Radiator model, check fan belts, radiator for obstructions, etc.
Engine stops cranking and fault lamp lights, after cranking approximately 75 seconds.See engine service manual for troubleshooting fuel system. After correcting problem, reset engine monitor relay by placing Run-Stop/Reset-Retrieve switch to Stop/Reset, then back to the required running position.
Fault lamp lights immediately after engine starts.Check for: Overspeed condition as engine starts.

Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing.

Fuel consumption

RatingLoadL/hgal/h
Prime100%19.068.22
Standby100%15.558.7

Available documents

Operator's manual — 21000 engine (Cummins/Onan)

This page was generated from the 1 manufacturer document above by automated extraction; every figure shown is copied from one of them. How the data is compiled.

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