High Yanmar oil pressure

[sailorboy1]

My oil pressure pegs high even with the engine off! This started late last year but I didn't get to it but now that the boat is back in the water I need to fix it.

I don't see anything wrong with the wiring but haven't pulled the harness apart yet to look there (I've learned to start at the harness if the connector is OK).

But since I know that if the sender wire has an open the pressure reads low so the high reading would have to be a short. This is unlikely but the temp gauge was replaced last year and I think the problem started shortly after that so maybe in the back of the gauge the wires have slipped and are grounding from that replacement work (I didn't do it).

I'm going to pull the wire off the sender and see if the gauge then reads low before I get too carried away.

But anyone else have seen a high oil pressure on a Yanmar 4JH3E? (and it's not the oil or filter as I just changed those and it didn't make any difference and this wouldn't make it peg with the engine off)

[delmarrey]

Turn on the key w/o the motor running. If the gauge drops to zero. Problem solved.
If not, you have a short or bad sender/gauge.

[sailorboy1]

The pressure was high with the engine off (see orginal question). Took the wire off the sender and the reading went to zero. This was good news as it means it isn't a wiring problem.

Turns out the send isn't a Yanmar unit as it has a custom panel made by Seaward for Hunter 400 series boats. So if someone comes across this thread with a Hunter 400 series you need to get 1 from Seaward (who also has those start button rubber covers)

[barnakiel]

Yep. At post #2, common problem. Seen it on Westerbeke temp gauge.

Pulling the sensor out and cleaning it may help too.

b.

[sailorboy1]

So after sending a couple of weeks looking for and $60 buying a new pressure sender; it turned out to be a $6 gauge instead (plus $9.54 shipping).
next time I'm just going to buy a matched gage and sender from the start!

So my engine panel now has a new oil gauge, a new temp gauge, new push buttons, a soon to be new warning light. So I'm starting to think my tach issue is the tach as the panel seems to the common problem.

[FrankZ]

Originally Posted by Don Lucas

So I'm starting to think my tach issue is the tach as the panel seems to the common problem.

That would make it too easy.

[delmarrey]

I could have sold you a whole brand new panel with the oil sender, but Frank got it!

[Lancerbye]

With a name like Lucas you should expect these little electrical problems. lol Lucas Prince of Darkness.