I have a strange problem with my 292 in my 63 F100. When I start the engine, the oil pressure will initially jump up to about 40 psi but over the next 30 seconds will drop to zero. There is no change I the sound of the engine when it goes to zero like you would expect with no oil pressure and raising the rpms does not bring the pressure up.

Any ideas?

Thanks
Drw

inlet tube to pump nut loose, or the seal is bad are the most likely

In the mean time, don't run it at all with 0psi.  You don't want to wait for a noise before you shut it off.  By that time it may be too late.


Lawrenceville, GA

Check with a  mechanical gauge,,,if the same thing occurs, pull the pump plate to see if rotor is moving. Or do this first.

I had exactly the same problem once, and it was the seal at the tube to the oil pump. It would hold just enough suction to get pressure from a full pan, but then pulled air as the pan level dropped.

miker
55 bird, 32 cabrio F code
Kent, WA
Tucson, AZ

Thanks for the advice. I will check the tube.

I am using a mechanical gage, and definitely not driving it like this!

Drw