Yanmar — Checking Fuel Injection Timing

Adjustments · Fuel Injection Pump

From a Yanmar service manual covering: YDG2700, YDG2700EV-6EH, YDG2700EV-G6EH, YDG2700EV-GEH, YDG3700, YDG3700EV-6El, YDG3700EV-GEI, YDG5500, YDG5500EV-6El. Check it applies to your exact model before use.

Applies to: Yanmar YDG2700, Yanmar YDG2700EV-6EH, Yanmar YDG2700EV-G6EH, Yanmar YDG3700, Yanmar YDG5500, Yanmar L70V engine, Yanmar L100V engine, Yanmar L4sV L70V L100V engine

Procedure

1. Verify actual piston TDC.
2. Ensure the fuel injection pump is primed with fuel.
3. Remove the cooling fan housing and recoil starter.
4. Highlight the TDC timing mark on the cylinder cooling fin.
5. Highlight the TDC and target timing marks BTDC on the flywheel timing grid.
6. Remove the high-pressure fuel injection line.
7. Set the throttle control lever to the minimum speed position.
8. Remove the injection pump inspection window cover plate and gasket.
9. Install the fuel adjustment jig (Yanmar P/N 114771-92310) in the inspection window.
10. Install the spill-timing tool onto the fuel delivery valve.
11. Turn on the fuel supply and rotate the flywheel clockwise until fuel is pumped.
12. Slowly rotate crankshaft until the fuel level just begins to move, then stop.
13. Wedge the flywheel and check alignment of the target timing mark to the TDC mark.
14. If marks do not align, adjust the fuel injection timing.

Full service-parts list: Yanmar YDG2700EV-G6EH →

Source: Yanmar 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.

More Yanmar repair guides →