Yanmar 4TNE88 — Checking the L.O. pressure switch
Testing & diagnosis
For the Yanmar 4TNE88, from the Yanmar service manual.
Applies to: Yanmar 4TNE88, Yanmar TNE series engine
Procedure
- Remove the connector from the L.O. pressure switch.
- While running the engine, bring the tester probes into contact with the switch terminal and cylinder block.
- If the tester shows continuity, the L.O. pressure switch is defective.
Tools required
- Tester Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
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.