Yanmar 3ym20 won’t run (approx 450 hrs on engine)

[slorandy]

Had the drive gear for the injector pump come off (apparently the nut came undone). Had a diesel mechanic re-attach and reset the timing. The engine won’t start. We also removed and tested the injector pump, and bled. Still no luck. After $1500 in labor charges the mechanic gave up, so I’m looking for suggestions. Where I live there isn’t much in the way of mechanics.

One option is to mount an outboard engine so I can get the boat to a yanmar mechanic about 100 miles away. 2nd question is, has anyone mounted a outboard motor mount on this type boat?

Thanks for the help and ideas…

 

[dlochner]

Welcome to SBO, sorry for your woes.

Mounting an outboard would be an expensive proposition and would offer marginal help. In the end it might be cheaper to just hire SeaTow or TowBoatUS to tow the boat.

Have you changed the filters? Do you get fuel flow from the pump? Is there enough compression?

If the drive gear for the pump came off, I have to wonder if there is more damage to pump.

 

[slorandy]

Thanks Dave. We had the injector bench tested and it was ok. We did not check compression since I did not think that would have been affected. I’ll need to review the notes if he actually verified the injectors were squirting fuel.
I’m also wondering if maybe he set the injector pump timing incorrectly.

 

[dlochner]

A poor repair is a possibility. Did he have access to the shop manual for the engine? There are copies of some Yanmar manuals on the SBO site.