The Isuzu 4LE1T is a 2.2 L 4-cylinder turbocharged engine rated at 1800 rpm, producing up to 46 kW. It powers generator sets from Energy Pac, Westquip and Winco, including the ML30IMRD, WQ35LT and DE30I4. It holds 8.6 L (2.3 gal) of oil and 50 L (13.2 gal) of coolant.
Also known as: Isuzu 4LE1T
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| Oil capacity | 8.6 L |
|---|---|
| Coolant capacity | 50.0 L |
| Displacement | 2.2 L |
| Cylinders | 4 |
| Aspiration | Turbocharged |
| Rated speed | 1800 rpm |
| Gross power | 46 kW |
Shared across brands: Energy Pac, Westquip, Winco
| Symptom | Cause | Remedy |
|---|---|---|
| Engine does not start — Starter does not run | Battery in discharging | Charge |
| Engine does not start — Starter does not run | Defective starter switch | Replace |
| Engine does not start — Starter does not run | Defective magnetic switch | Replace |
| Engine does not start — Starter does not run | Poor contact of starter bush | Repair or replace |
| Engine does not start — Starter does not run | Defective starter | Bring it to a specialty shop for repair |
| Engine does not start — Starter does not run | Loosened connector or broken wire | Retighten or replace with new wiring |
| Engine does not start — Starter runs but does not start | No fuel injected | |
| Engine does not start — Starter runs but does not start | Air mixed in fuel pump | Retighten, replace packing, bleed air |
| Engine does not start — Starter runs but does not start | Clogged fuel filter | Clean |
| Engine does not start — Starter runs but does not start | Low compression pressure | |
| Engine does not start — Starter runs but does not start | Defective valve, spring, gasket, etc. | Overhaul |
| Engine does not start — Starter runs but does not start | Poor operation of glow plug control resistance | Replace |
| Engine does not start — Starter runs but does not start | Abnormal injection timing | Adjust |
| Engine does not start — Starter runs but does not start | Defective nozzle | Repair or replace |
| Engine does not start — Starter runs but does not start | Stuck solenoid or poor operation of engine stop solenoid return | Repair or replace |
| Engine does not start — Starter runs but does not start | Defective injection pump | Bring it to a specialty shop for repair |
| Engine does not start — Starter runs but does not start | Stuck EGR valve (opened position) | Replace the EGR cut solenoid and valve case by the set; Refer to "EGR Control" in the Exhaust System section |
| Engine starts but does not run continuously. | Air mixed in fuel pump | Retighten, replace packing, bleed air |
| Engine starts but does not run continuously. | Disordered idling | Adjust idling |
| Unstable engine idling — Idling speed too high | Defective control lever adjustment | Repair or replace |
| Unstable engine idling — Idling speed too high | Defective injection pump | Bring it to a specialty shop for repair |
| Unstable engine idling — Idling speed too high | Defective idling adjustment | |
| Unstable rotation at medium speed (Hunting) | Governor spring deteriorated | |
| Unstable rotation at medium speed (Hunting) | Crash in fuel pipe | Replace |
| Unstable rotation at medium speed (Hunting) | Defective valve return | Adjust |
| Unstable rotation at medium speed (Hunting) | Cracked, clogged or bent high pressure pipe | Replace |
| Unstable rotation at medium speed (Hunting) | Defective nozzle | Repair or replace |
| Unstable rotation at medium speed (Hunting) | Uneven compression pressure | Adjust |
| Unstable rotation at medium speed (Hunting) | Defective injection pump | Bring it to a specialty shop for repair |
| Unstable rotation at high speed | Air mixed in fuel | Bleed air |
| Unstable rotation at high speed | Clogged fuel filter | Clean or replace |
| Unstable rotation at high speed | Uneven fuel injection | Adjust |
| Unstable rotation at high speed | Poor valve clearance adjustment | Adjust |
| Unstable rotation at high speed | Defective injection pump | Bring it to a specialty shop for repair |
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 Isuzu 4LE1T.
| Item | Spec | Capacity | Part # | Interval | |
|---|---|---|---|---|---|
| Air filter | Replaceable Element | — | |||
| Fuel filter | 8944015310 | Amazon eBay $86.33 NAPA $16.78 | |||
| Oil filter | Spin-on | 5876100080 | Amazon eBay $16.89 PartsGeek $7.98 NAPA $14.75 | ||
| Oil | Engine oil | — |
Pooled from every document that names this exact engine — confirm the interval and part number against your unit's serial number.
Step-by-step procedures compiled from the Isuzu service manual for this engine.
Cross-referenced via Donaldson + OEM/engine-maker interchange — options to verify against your serial number, not confirmed for every exact variant.
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.
The Isuzu 4LE1T engine has an oil capacity of 8.6 liters.
The Isuzu 4LE1T has a displacement of 2.2 liters with 4 cylinders.
The Isuzu 4LE1T powers 3 generator set(s), including Energy Pac ML30IMRD, Westquip WQ35LT, Winco DE30I4.
The Isuzu 4LE1T uses oil filter part numbers Isuzu 5876100080, Donaldson P550162, Wix 51334.
The Isuzu 4LE1T uses fuel filter part numbers Isuzu 8944015310, Donaldson P502166, Wix 33263.
The Isuzu 4LE1T uses air filter part numbers Isuzu 5864014350, Isuzu 8972599390, Donaldson P775687.
A commonly reported issue on generators using the Isuzu 4LE1T is: No AC output from generator. Cause: Defective Diode.