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Oil pressure problems... Ideas?

Below is an over simplified oil flow schematic of an o320.
the vernatherm is essentially blocking flow thru rubber hoses when oil is cool,
Oil bypasses rubber hoses and continues thru the circuit. A blocked rubber hose will effect cooling, not system oil pressure. ADK states he removed oil temp bypass (vernatherm?) during trouble shooting. This would eliminate cooler and hoses as culprit.
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A cracked crankshaft or bad internal plug in the crankshaft can cause this type of symptoms (not sure if you have hollow crank or not). Bad bearings should drop pressure a lower RPM not higher.
DENNY
 
After a Harley engine O/H when I was a kid, that old mechanic(Thank you Eugene McMahon )told me to close the throttle every ten minutes or so to pump extra oil through the engine during the break in. So I have watched the oil pressure gauge on every engine I operated since then and every one momentarily increases 2 to 5 pounds when the throttle is closed. Why? I don't know. Just interesting trivia I guess. What's it have to do with this problem? Probably nothing as the increase is only the width of the needle.
 
Yah so I finally got the motor back from the shop and hung on the plane. Got about half dozen hours on it so far and one oil change. Seems to be running like it should.

Short answer I got from my engine builder is that he replaced the accessory case, new pick up tube and externally adjustable oil pressure regulator.

I’m GUESSING the accessory case made the difference. However he states that new gears and the old acc case tolerances were within spec. Now I have new gears and new case.

Pegs steady at 85 psi (very top of green arc) at 2400 rpm cruise. I spose I could back it off with the external adjuster now, but I’m still feeling it out. Hopefully this is the start of some great flying.

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There's no pickup tube in a Lycoming. It's cast into the sump. If you paid for a new pickup tube? Get your money back!
 
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My recent experience? My biggest fear was mis-alignment of the sump gasket at the pickup gallery. Really easy to do on a hanging motor. That and that I had Casper gaskets and Superior returned me a B&C adaptor spacer! I fashioned my own gaskets for that. Fun with airplanes continues!
 
Pegs steady at 85 psi (very top of green arc) at 2400 rpm cruise. I spose I could back it off with the external adjuster now, but I’m still feeling it out. Hopefully this is the start of some great flying.
Don't touch it. That's where mine runs all the time. Just watch it when starting in cold weather. It may go higher so let it run to warm up a little before you open the throttle. The high pressure will come down when warmed.
 
Good point skywagon.

I don’t have a oil cooler block off and it’s been around 20f here flying, so I haven’t seen temps over 140 yet.


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