Oil pressure.

[philtheskipper]

My oil pressure guage started to fall to 0 every now and then the other day. Engine seems to be running fine and there is oil squirting on top of the lifters as usual. Wires are good behind the guage. Where on the engine is the oil pressure sensor/wire located? It's a 1979 mercruiser 120. I have no idea what to check or what to look for.

 

[lenny2113]

Re: Oil pressure.

Oil pressure sender is located on the lower left side of your engnine.<br /><br />Check this link. There is a picture of the sender there. Yours might be slightly different but you'll get the idea.<br /> http://www.mindspring.com/~houlihan/merc/oilpress.htm <br />I hope it helps.

 

[Walter]

Re: Oil pressure.

Problem could be the oil pressure sending unit. However, I suggest you first check the wiring and connections in that circuit. Insure there is constant 12 volts to the ignition (positive) terminal of the gauge with the key switch on (you don't need to start the engine). To check the sender's wiring up to your gauge...connect one end of a jumper wire to the wire on the sending unit and the other end to battery ground. Turn the ignition key on. Your oil pressure gauge should be pegged at it's max reading (or a little above). While someone watches the gauges...check the connections at the gauge, sending unit, harness connector etc... Any fluctuation of the gauge will indicate a bad connection at that point.<br /><br />Walt

 

[philtheskipper]

Re: Oil pressure.

Thanks for the info! I'll check it out today and let you know what happens.