A friend of mine has a matching numbers 69 Dart GTS 383 4 speed car. Since he put the car away last winter,the car has had no oil pressure on start up after sitting. If he pulls the coil wire off before starting it up,and cranks it over until it shows oil pressure on the mechanical guage,then its fine until the next time it sits,then it's the same scenario. He has replaced the oil pump three times,with three new,different pumps,and it does the same thing. This summer he drove it to a few shows that were a couple hour rides,and after diving the car alot,it didn't have the problem,until it sat for the last two weeks,then after trying to fire it up again,it was knocking and clacking until he shut it off,and primed it with the coil wire off again,then it was fine. He needs help figuring this out,as the car has the matching numbers engine,and he dosen't want to hurt it. He is getting ready to drop the pan to see if there are problems with the pickup to the oil pump. Any ideas as to what else could cause the loss of prime issue,after sitting?

It has to be something in the path between the pickup and the pump, pulling the pan is the best idea , let me know how that works out for him since I need to do the same thing on mine to clean out the pickup of the pieces from the original cam gear breaking up.

try a different filter. Wouldn't be a Fram would it

I just spoke to him on the phone,and he said he changed the oil and filters every time he swapped oil pumps. The filters were WIX filters.

that eliminates the filter as the culprit

After what I read about the Fram filters I run WIX filters on all my cars.

Have him pull the oil pan and clean the valve seal pieces out of the pickup tube screen, it must be nearly clogged.

I suppose it's possible,but the engine was rebuilt about ten years ago. It dosent puff any oil on startup,like most cars would if the valve seals were bad.

I reread your (original) post. I'm assuming it wasn't always like this but now (after this particular extended storage) it clatters real bad & it didn't b 4? How long does he now have to crank it w the coil disabled b 4 the psi come up? OT but I'd suggest he ground the coil wire rather than making an open circuit but if we can fix the prob that'll take care of that .

The oiling issue started this June,when he broke the car out of winter storage. After the engine cranks about twenty turns it starts showing oil pressure on the guage. once it gets prime the car is fine no matter how many times he runs it. After it sits overnight,it has the same problem the next time he trys to fire it up. If the problem persits after he pulls the oil pan,I will suggest a kill switch,so he can crank it safely,without it firing until it's primed. Plus it may stop a potential thief too.

Yeah it's gonna be interesting to find what happened (what got stuck/or cracked open) while it was sitting immobile in storage and whether it's downstream or up stream from the pump as it isn't the pump or filters will all of that changing out that he did

Yeah,thats not the easiest task in a big block A body!