Trouble with Yanmar 4LH 240

[RattleandHumNC]

I own Capn Pats last boat, the Rattle and Hum. I am having some issues with one of the Yanmars. The oil pressure gauge is going haywire despite having good pressure. After running for a few minutes at cruise, the oil pressure gauge goes to zero and the engine pulls back to idle. We have traced the problem to a bad sending unit and that is getting replaced today. My mechanic has said that these engines are mechanical and should not have an auto shut off. Is this correct?

[Bruce]

Unless once the boat was delivered to Patrick, first owner, and then modified, I did the engine electrical and there was no such thing as auto shut down installed as both myself and Pat didn't believe in it. Pat more so after a sportfish he was running in Puerto Aventuras Mexico lost an engine on throttle down for low oil in the rough inlet and almost lost the boat up on the rocks. As the boat was spinning he was able to fire the dead engine and backed down thru the inlet.

They are mechanical engines and to throttle down, someone would have to bring the handle back, unless there was a fuel issue.
Those engines require power to fuel solenoid to shut down.

[RattleandHumNC]

Thanks Bruce. I was hoping you would reply as I did not know how to get up with you directly. I have another issue then because she has pulled back to idle and even shut down once as the oils pressure went to 0. We will keep chasing it. Thanks

[RattleandHumNC]

Oil pressure issue was fixed with new sending unit.

Throttling back was fixed by going through fuel system and tightening/resealing all connections. Also, went through the Racors really well.

She is running great!