Yanmar couldn't get it up

[arf145]

The oil pressure that is, and it's never happened before, I swear!

OK, really, it never has happened before. My 22 yr old Yanmar 2GM20F always starts right up--like less than a second. Little or no smoke, runs strong, the oil pressure alarm goes off after a couple seconds of running. But the other day, after starting the engine to bring the boat back in, the oil pressure alarm stayed on. Cut the engine, waited a bit and verified that the oil level was good. Restarted, then reved it up to 1000 and the alarm went off. It then stayed off at idle, through running for a half hour, and then idling some more.

I don't believe the engine has a huge # of hours on it, but don't know this for sure. Don't have an oil pressure gauge. I use the recommended 30 wt diesel oil. Could the sender for the oil pressure alarm be going bad?

Thanks.

[scottyt]

yes the sender can go bad, but for safety i would not run for now.

if you take the sender out a good auto machine shop should be able to test it. heck you might be able to get a new one that works at napa auto part, just make sure the pressure setting is the same

[hellosailor]

Those pressure senders DO go bad. Or, the pressure adjustment in your oil pump (often a spring) could be bad. There's usually a resistance check you can perform to test the sender but if a new one is $15-20 and the old one is already ten years old, it might be simpler to just replace it.

While it is out, you stick a mechanical oil pressure gauge into the port (or whereever an oil pressure gauge can be used on your engine) and double-check that you really have oil pressure. Better to be conservative when it comes to oil problems. This could also be the tie to consider plumbing in a real 9electric) oil pressure sender and gauge and "just do it".