The Cummins/Onan 4.0EGHW is a 4 L natural engine rated at 3600 rpm. It powers generator sets from Cummins/Onan. It holds 1.16 L (0.3 gal) of oil and 1.1 L (0.3 gal) of coolant.
Also known as: Onan 4.0EGHW
| Oil capacity | 1.16 L |
|---|---|
| Coolant capacity | 1.1 L |
| Displacement | 4.0 L |
| Aspiration | Natural |
| Rated speed | 3600 rpm |
How to read your Cummins/Onan engine serial & model number →
| Symptom | Cause | Remedy |
|---|---|---|
| Engine cranks slowly (electric start models) | Low battery | Check battery electrolyte level and charge |
| Engine cranks slowly (electric start models) | Bad battery connection | Clean and tighten all battery and cable connections |
| Engine cranks slowly (electric start models) | Oil is too heavy | Replace with lighter oil |
| Engine cranks slowly (electric start models) | Load is connected | Always disconnect load while starting |
| Engine won't start | Out of fuel | Add fuel |
| Engine won't start | Fuel supply valve closed | Fully open fuel supply valve |
| Engine won't start | Carbon deposits on spark plug | Remove and clean or replace spark plug |
| Engine won't start | Low oil level | Add oil as necessary |
| Engine won't start | Loose or worn spark plug lead | Check spark plug lead connection |
| Engine won't start | Faulty spark plug | Remove and clean or replace spark plug |
| Engine won't start | Dirty fuel filter or generator set at too steep of an angle | Check fuel filter and generator set angle |
| Engine won't start | Governor out of adjustment or lean fuel mix | Contact an Onan service center |
| Exhausting black smoke | Choke closed | Open choke |
| Exhausting black smoke | Dirty air filter | Clean or replace air filter |
| Exhausting black smoke | Rich fuel mixture | Contact an Onan service center |
| Unit runs then stops | Open DC circuit breaker due to an overload | Remove all loads, reset circuit breaker, check for an overload or shorted battery. Do not exceed generator set rated load specifications |
| Unit runs but surges | Out of fuel | Add fuel |
| Unit runs but surges | Low oil level | Add oil |
| Unit runs but surges | Excess oil | Reduce oil level |
| No AC output voltage | Open AC circuit breaker due to an overload | Remove all loads, re-set circuit breaker, check tools or appliances being used for defects. Do not exceed generator set rated load specifications |
| No DC output voltage | Open DC circuit breaker due to an overload | Remove all loads, reset circuit breaker, check for an overload or shorted battery. Do not exceed generator set rated load specifications |
Fault codes and symptom→remedy steps extracted from this engine’s service/owner documentation; verify against the official manual before servicing.
Compiled from service & troubleshooting documentation across every generator set that uses the Cummins/Onan 4.0EGHW.
The Cummins/Onan 4.0EGHW engine has an oil capacity of 1.16 liters.
The Cummins/Onan 4.0EGHW has a displacement of 4.0 liters.
The Cummins/Onan 4.0EGHW powers 1 generator set(s), including Cummins/Onan 4.0EGHW.
A commonly reported issue on generators using the Cummins/Onan 4.0EGHW is: Engine won't start. Cause: Out of fuel. Fix: Add fuel.