Isuzu 4le1t — Inspection and adjustment of injection timing
Adjustments · Injection pump
For the Isuzu 4le1t, from the Isuzu service manual.
Applies to: Isuzu 4le1t, Isuzu 4LE1 engine
Before you start
- Adjust the shims for each injection pump of four cylinders at the same time.
- Be careful with dirt getting inside when removing/installing the delivery valve or spring.
Procedure
- Remove the No.1 cylinder injection pipe.
- Remove the delivery valve holder, valve and spring of the No.1 cylinder injection pump.
- Reinstall the delivery valve holder and tighten leaving the valve and spring removed.
- Rotate the crankshaft slowly feeding fuel, stop when fuel stops flowing/bulging.
- Check the timing mark position of the crank pulley mark groove.
- Adjust injection timing with the shim between injection pump and cylinder block.
- Reassemble the delivery valve and tighten to specified torque.
- Install the injection pipe and tighten the sleeve nut.
Tools required
- Wrench Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Injection timing: BTDC 2°
- Delivery valve holder: 39.2 — 44.1 N·m {4.0 — 4.5 kgf·m/28.9 — 32.5 lb·ft}
- Sleeve nut: 14.7 — 24.5 N·m {1.5 — 2.5 kgf·m/10.8 — 18.1 lb·ft}
- Shim: 0.1 mm changes timing approx. 0.6 degree
Full service-parts list: Isuzu 4le1t →, Isuzu 4LE1 engine →
Source: Isuzu service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.