72 318 Scamp. Low oil pressure 1 minute after startup.

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Go ahead and paint that engine bay blue to match the car while the engine Is out!! :poke:
Lol
 
I might paint it. I am going to pressure wash everything today. Do a compression test and cylinder leakage test.
 
Well I have 60 psi oil pressure now when using the Summit Mopar oil priming tool. I read a post here on how to turn the harmonic pulley to get oil to the rockers. It worked great! Thanks everyone.

I don't have oil to the rockers for cylinder # 8. Turns out the left and right rockers are switched! So the pushrods are rubbing on the side of the head.
Also number 6 intake pushrod appears to be bent!

Taking off the rocker shaft no to clean and swap the two rockers.

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Very good detective work! Have you looked at the hex end of the intermediate shaft to see if the corners are rounded?
 
No I haven't. I didn't think about that. Could that cause low oil pressure? The engine has been rebuilt and except for using lots of silicone it doesn't look bad so far.
I will post a picture of the oil pickup. I think that it is too far up from the bottom of the pan. What do you think?

This is my first Mopar rebuild so sorry for asking obvious questions.

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Ah, yes... with that angle on the pickup, that is messed up! Makes sense to loose oil pressure. The stock pickup ought to be just touching the pan; it picks up through the side.
 
Great that makes me feel better! If you zoom in on the picture you can see that the siliconed the oil pump to the cap. I should probably remove that and clean everything on the oil pump and pickup. Would you bolt the oil pump directly to the main cap. Or with a gasket and maybe permatex #2?

I really do appreciate everyone's help with this problem.
Thanks everyone.

One more question.
I looked at the pistons with a camera and I say a .040 on one piston. They appear to be flat tops with 4 valve relief cuts. Would these be stock compression pistons.
I did do a compression test and all cylinders were between 120 to 125 on a stone cold engine. That doesn't sound like a lot of compression to me.
 
I prefer a gasket... others don't use them. If you use a sealer, it should just be a skim coat.

Both the pistons description and the compression readings say low compression; probably 8:1 or a bit less. Those compression numbers are stock /6-land. No doubt low compression replacements, but the stock 72's would be that low; smog era stuff.
 
nm9stheham said:
Why wait 2 days? THAT's the hard way....LOL
Click to expand...
I made mine out of a scrap chunk of round stock that came off an old boat trailer I scrapped out years ago.

While you are at it I'd replace the oil pressure sending unit if you have one...
 
Oh I have mechanical oil pressure gauge so I don't have a oil sending unit. Used the Summit racing mopar primping unit. It worked perfectly.

Zoom in on the oil pickup unit. It has grey silicone rubbed on the outside of the pipe. Maybe it had a fracture or leak in it. Think that I'll replace it and maybe the pump too.

Any brand or part numbers that I should get? I really don't want to pull it out again for the same issue.
 
The oil pump pickup should be completely parallel to the oil pan rails and almost if not just a little touching the bottom of the oil pan.
 
Scampi said:
Thanks RustyRatRod.
Get a new pickup? Or bend to fit?
Click to expand...

No need to bend. Just grab it and turn it counter clock wise until it's flat with the pan rail. It screws into the pump.
 
The threads are NPT. If it feels to loose when you turn it CCW to get it level, you may have to remove the oil pump and turn it CW a full turn so that it is snug. You don't want it sucking air or rotating out of shape again on it's own.
 
Scampi said:
Zoom in on the oil pickup unit. It has grey silicone rubbed on the outside of the pipe. Maybe it had a fracture or leak in it. Think that I'll replace it and maybe the pump too.
Click to expand...
OK, yes, replace the pickup, or at least scrape off the silicone and see what is going on underneath with the tube. I bet you are right, that it is covering a fracture.
 
Think that I will look it all over after work tonight. If I need a pickup or pump I will get that so the way. They was just some hard bits in pan. Looked like supper brittle rubber or plastic. No bearing shavings.
 
Scampi said:
Think that I will look it all over after work tonight. If I need a pickup or pump I will get that so the way. They was just some hard bits in pan. Looked like supper brittle rubber or plastic. No bearing shavings.
Click to expand...
The super brittle rubber is usually time hardened valve stem seals. That equals replacement time. They will continue to break down and plug the oil pump pickup and pump. Ask me how I know.
 
Jadaharabi said:
The super brittle rubber is usually time hardened valve stem seals. That equals replacement time. They will continue to break down and plug the oil pump pickup and pump. Ask me how I know.
Click to expand...

Looks like somebody did replace them. I can see bright blue umbrella type seal under the valve springs. They seem to be floating on the valve stem. It doesn't seem that they stay affixed to the top of the valve guide like on some over engines that I have worked on.
Thanks for the heads up.
Looks like they installed a double roller timing chain also. So that is a step up from the nylon coated timing gear.
 
Pull the pump and take the cover bolts off, and look for scoring between the gears, believe it or not those little pieces of valve stem seals will make marks in the gears, replacement chain, it might have spit the nylon gears.
 
That is the same one I always buy.
 
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