Are we talking about an oil pressure SWITCH or a sender?
I have had chronic problems with oil pressure switches, the one that works the yellow light.
I don't think I have had a Volvo with an OEM gauge - all mine have had idiot lights.
But the celery wagon did have an aftermarket gauge with copper line going to a "T" with the idiot light switch on the other side.
I have had engines that put up pretty high oil pressure. I put some washers under
the old-time pump's spring in my big-bore engine and had oil pressures of 130 psi or more.
Not sure how much more but it eventually did blow out one of the orange seals on the oil line in the crankcase.
That limited oil pressure to about 30 psi but it ran that way for a couple years before
I opened it up and diagnosed the problem. At that time there was no apparent engine damage.
After removing the washers the oil pressure ran from 25-65 psi until the short shaft fell out of the pump
and the loose gear milled a postage-stamp-sized hole in the side of the pump.
After that the oil pressure was zero and the engine was subsequently damaged, #2 rod bearing to be specific.
Other than possibly blowing the oil line seals I don't see much of a problem in
having a high oil pressure but I think 100 psi is probably enough.
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George Downs, Bartlesville, Heart of the USA!