Yanmar 4TNE88 — Measuring the injection pressure of the fuel injection valve
Testing & diagnosis
For the Yanmar 4TNE88, from the Yanmar service manual.
Applies to: Yanmar 4TNE88, Yanmar TNE series engine
Before you start
- Thoroughly remove carbon deposits from the injection nozzle before measurement.
Procedure
- Thoroughly remove carbon deposits from the injection nozzle.
- Connect the fuel injection valve to the high pressure pipe of the nozzle tester.
- Pump the lever slowly and read the pressure gauge when injection starts.
- If measured pressure is lower than specified, replace the pressure adjusting shim with a thicker one.
Tools required
- Nozzle tester Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Injection pressure per engine specifications
Full service-parts list: Yanmar 4TNE88 →
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.