yanmar 4 lha not starting

[keith c]

My port engine yanmar 4 cylinder was not starting. I had a bad battery which I replaced and then replaced the starter solenoid which appeared to be bad. Still no start. My mechanic is now saying the starter shut off system between the engine shut off switch and fuel pump has 12 volts in it which should not be there and is shutting off the fuel pump. I am no expert and I fear my mec. is over his head. I need any help the mainship forum brain trust can provide!!!

 

[DavidM]

Your mechanic is definitely over his head if he has put in a new battery and starter solenoid and still hasn't fixed the problem. How can a starting solenoid "appear" to bad. Two minutes with a voltmeter will tell you for sure.

Try jumping the starter motor with a screwdriver. That bypasses the solenoid. If that works then the problem is in the starting solenoid circuit.

David

 

[Dougcole]

Did you check the start relay? Common point of failure on the 4lha. Its on the opposite side of the motor from the starter.

 

[Comodave]

Not familiar with Yanmar but on our last boat we had a stop switch go bad and stop the engine from starting. The mechanic found it in literally 5 minutes.

 

[Ski in NC]

So is the stop solenoid energized? That will keep it from starting. It is energize to stop engine, if energized on start, engine will not start, just crank over.

 

[High Wire]

Does it crank but not run or just not crank at all?
No crank, try Neutral safety switch. Hold start sw and wiggle the FNR lever. Or just bypass it with a jumper.