Merc 260 high oil pressure---Is it a problem or not?

[dwojo]

I have a Merc 260. My oil pressure is 75 psi @ 4000 RPM but the engine seems to be running fine. First, where is the sending unit located? Besides the sending unit, is there anything else I should look at to fix the situation? Can I get the sending unit at an auto parts store by asking for a Chevy 350 sending unit and will that work? Also, if I replace the sending unit and the oil pressure is still high, what should I do? <br /><br />Thanks a lot for any help you can give me!

 

[snapperbait]

Re: Merc 260 high oil pressure---Is it a problem or not?

The oil pressure sender usually needs to be from the same manufacturer as the gauge... <br /><br />Is it at 75 psi with the engine up to operating temp and has it always been that way?<br /><br />What is the psi at idle?

 

[dwojo]

Re: Merc 260 high oil pressure---Is it a problem or not?

The psi at idle is about 40 psi at operating temp. As for it always being that way...I couldn't tell you because I just bought the boat.

 

[magster65]

Re: Merc 260 high oil pressure---Is it a problem or not?

Those pressures are typical for a high volume oil pump and 'snug' bearing clearances. I don't think it's a problem.

 

[dwojo]

Re: Merc 260 high oil pressure---Is it a problem or not?

I'm new to I/O's, so I don't know if they're supposed to have oil pressures like a car, so I apologize if some of my questions seem dumb!<br /><br />Back to the topic..at WOT the oil pressure is sometimes off the gauge (80+ psi)-should I be worried about this? Before I freak out, besides changing the sending unit and/or gauge, is there anything else I should check to see if something bad is going on in there?

 

[kenimpzoom]

Re: Merc 260 high oil pressure---Is it a problem or not?

Try changing the oil. Someone could have put straight 50 wt oil in it. Also check it for water.<br /><br />How old is the motor?<br /><br />Did you ask the previous owner about the oil pressure?<br /><br />Ken