C/S prop surge, what oil pressure reading?

[Kahuna]

Im troublshooting an inverted oil pressure problem.
I noticed recently that during sustained inverted, oil pressure slowly drops to zero over ~ 6 seconds. I stay there for about 5 seconds at zero, then return to upright. Oil pressure returns when upright. Repeat. Same story. Try and give her a good whack while inverted to unstick ball valve. No joy.

There is no prop surge. RPM remains constant.

Last year I moved my oil pressure sensor from the uppper right to the upper left. Thread on that here.
Its been about a year since Ive done any sustained inverted work.

It would seem that perhaps I have a ball stuck in the valve (Raven system). The one piece of data that is throwing me off is the prop not surging.

The one thing I have changed since the last inverted working senerio a year ago has been the moving of the oil pressure to the upper left here.

Before I spend the better part of the day getting to and removing the valve assembly for inspection, I would like to know if you would expect the prop to surge at zero oil psi, at some time after zero? Some time before?

If the answer is at, before, or shortly after, then I am suspect of the oil pressure port location.

Raven Diagram. Last page
Raven system. How it works.
Its like the Christen and is a competitive product to them.

Thanks for your help.

[L.Adamson]

FWIW, the prop governor has it's own built in pump to increase oil pressure. At least it's not entirely dependent on the engine pressure.

L.Adamson

[frankh]

Never seen this with my Raven..Either you have a stuck valve..or..Ohh, you are using the proper vacuum pad take off adaptor I assume?

Have you called Raven? they are pretty helpful.

Frank

[Kahuna]

Originally Posted by frankh

Never seen this with my Raven..Either you have a stuck valve..or..Ohh, you are using the proper vacuum pad take off adaptor I assume?

Have you called Raven? they are pretty helpful.

Frank

Yes, all installed per Raven instructions with their parts.
Rob at Raven was not sure if the alternate sensor location could be the culprit. He said stuck valves are very rare, especially in a well used engine, which mine is, whether or not you spend any time inverted.