I once had a 440 that refused to prime after filter changes. Packed the oil pump with grease and it primed fine. Drove through two oil/filter changes and in a row with it acting like this until it suddenly lost all pressure a few minutes after starting. Pulled the oil pump and found small rust pits on the reliefe valve stem. Scotch brited them off and have run the engine for ten years and no problem since. Just a thought... Let us know what you find.

I pulled the driver side valve cover off and found that I'm missing the #5 intake pushrod. Haven't taken the intake off to see where it went. I guess the lifter popped out and the pushrod went into the pan. I hope to get a better look this weekend. It has a wet sump stock oil system!

Well..... With a lifter missing..... It won't have pressure.

I guess the real question now is...... Why did that happen?

Really 500ciBee - look at your first post. Now you find you are missing a pushrod?

I think you left something out of the first post.

Amazing.

Thanks for the update and glad you tried the priming suggestion before starting the motor. So much for

Please keep us posted

And so is your comment

^^^ agreed, we're here to help, not to dump on people. what 68Plymouth said, now we gotta find what caused it to jump out.

Didn't the OP originally mention something about atunnel ram swap at teh same time as well?

I seem to recall that

Definitelly a missed lifter of the bore will drop the oil pressure BTDT. We can't say the missed pushrod will mean a lifter out of the bore ( I have bent some pushrods being out of its place and lifter still kept in place ), but it could be.

With a new oil pump, definitelly needs to pack up the pump rotors with grease or oil, but if it was already running, is not necesary

IMO, the two "most likely" scenarios for the pushrod coming out are.....

-if it has adjustable rockers, the adjuster backed off until the pushrod fell out.

-the pushrods are not quite up to the job at hand, and one of them crumpled under the stress

Before the oil change everything was fine,or so I thought. I had no idea that something was wrong before the oil change. Had oil pressure and the engine was running well. I warmed the engine up before changing the oil and it seemed normal. After the oil and filter change is when I had no oil pressure. This was a routine oil change. I've never had anything like this happen before.

Post some pics when you get to it. Something all would like to be informed about and to keep in mind. Certainly a huge anomaly.

Mr Murphys' handiwork, luckily he don't show up very often but he don't play when he does.

My apologies 500ciBee if I came across as criticizing you - I found it hard to understand how your engine didn't have a bad miss/vibration with a missing pushrod. I guess you can chalk it up to coincidence.

Was my initial exact thought when you made your post. Tough crowd!

Providing all was well before the oil change as stated the only way I could comprehend this happening is
A. the pushrod just happened to snap or bend at that particular time.
B. the lifter, if hydraulic may have collapsed enough before oil pressure pumped it back up.

I do find it a bit strange and even more so that the lifter jumped out of the bore unless one was winging it which is unlikely.

Finding the push rod may help determine the cause.

I found the problem! The lobe is wiped and the lifter is trashed. Must have been like this for awhile. Not sure if it was coincidence that after the oil change that the lifter wore through and collapsed the lifter and the pushrod fell out. New cam, bearings, lifters and pushrods I guess are in my future. Is it worth the effort to pull the motor out or do in car swap of the cam?

The best solution is pull the engine and clean all the debris out of it. There is a lot of metal floating around just waiting to cause problems.

Good luck.

Or there is already a lot of metal lodged in the bearings and piston skirts b/c you don't know how long this has been going on. Hopefully it isn't chewed up too bad.

x3