No oil pressure. Appears the gauge is functioning and the line isn’t clogged. A&P says might be issue with oil pressure relief plunger, but wanted to do some more research.
been sitting for awhile? IF it has been carefully take the oil temp bulb out and shoot it full of oil and lift the tail when doing this, to prime the oil pump.
Reason I asked about the oil filter is we put the Tempest adapter on a C85 and after that, no oil pressure. After much trouble shooting we found it was not the cause. The engine was just worn out and we got unlucky that it gave up after the change.
We put a “tee” in that line below #1 that goes to the oil pressure gauge. I like to pressurize the entire engine after a bottom end repair, but for the 65/75, one can attach an older oil can with a good trigger pump to the tee, give the engine 35 shots of oil, then crank and have good oil pressure.
A-65 pumps are notorious for needing this - they can be repaired. But just pump it up and go fly. Let it sit for more than a couple days, you will have to pump it up again.
Thanks Bob and others. I found my earlier copies of the manual and now have the 1968 and 1971 revisions in electronic format. This one did indeed sit for a bit and I'm hoping we can find the right result that keeps it going well past it's 100th year (coming up in only 17 more years).