oil pressure control

[karlp]

I've been working on a '75 2.0 in my shop. I have it on an engine stand with a gas tank, battery, relay board, the works. I've run 3 or 4 gallons of gas through checking things out. Great fun, but at some point I've got to say it's ready and do the install.
The oil pressure concerns me a great deal. It will be in excess of 90 psi on start up at idle, go off the gauge when I rev it a little. It'll go down to 70 psi after it warms up but still goes 90+ psi on revs.
My haynes manual shows an oil pressure control plunger on the drivers side of the engine, below the filler cap. I don't see one there. I see the one next to the oil filter.
Am I missing something? I'm measuring the oil pressure at the port where the oil idiot light sender is usually installed. I'm afraid I'm going to blow a seal or filter or something.

Thanks for any help.

Karl P.

[Tidybuoy]

There should be two areas where the oil relief valves are located. One is just next to the oil filter and you can see it when laying under the car (it looks like a large round screw - very flat & about the sixe of a quarter). The second one is located on the side of the engine opposite sied of the oil filter & cooler & is just about the center of where the push rod tubes enter the engine. it's about 2" up from the bottom of the engine. This second one has a "torx" type screw head and is smaller than the one under the engine.

Vern

[Dave at Pelican Parts]

The second one is not present in some/many 914 (and other Type IV) engine cases.

90 PSI at idle is a bit high. What weight of oil are you using? Unless you have very thick and/or cold oil, we usually only see 55-75 PSI or so before the pressure relief valve opens up. That's with the oil up to operating temperature, though--212F.

These measurements are generally taken at the same location you are using.

--DD

[karlp]

I'm using 20w-50.
I'll look again for the second one, and pull the one out at the oil filter and see if it is gummed up.
I'm seeing oil pressures of 90+, fully warmed up. I think no relief is relieving.