Fix for leaking oil pan

[Dartman61]

Hey guys need some help. I'm working on a 1970 340 Cuda. The engine is built to bracket race and is really quick. It has a Trimec 5 spd and aftermarket Bell housing (scatter shield type). The existing oil pan (8 qt) had pin holes and leaked significantly. The gauge indicates I'm pushing 100 PSI oil pressure on acceleration .



I pulled the pan and replaced it with a stock replacement (5 qt), from Summit along with a gasket kit. I installed and it still leaks at the ends where the pan is curved in a ½ circle. I removed the pan again and I got racing gaskets from Mancinni, Racing and replaced the cheaper set. The distance between the bell housing and oil pump makes for a really tight fit with the pan and gasket slightly wider than the opening. I trimmed the pan but still had to force the pan and gasket into place. I took it for a short run 15-20 minutes and it still leaks. I get a 3-5 inch puddle under the car and its coming from both the front and rear seal where its curved.

Anyone had this problem and if so did you find a fix?

Is the replacement pan just too cheap to make a good seal?

Classic industries has a replacement pan stamped 294 – would that be better?

Am I better off getting an original used pan?

Do I just need to get use to a leaky pan?

Any help is appreciated. I’m very frustrated at this point and not sure what to try next.

Thanks

 

[mygasser]

is it the sbm that can have a choice of rubber half moon seal thickness? if so you could have the wrong one fitted? or am i thinking of a different motor?
neil.

 

[Dana67Dart]

IMHO

Most seal failures are user error.

Sone seals need sealer some do not.

Letting the sealer cure properly is very important

Most rtv says to apply, let cure for some amount of time, then install and TORQUE to an amount.

Most people apply and torque and then fill and run it wondering why it's leaking.

I replaced a front timing cover on a 96 318. I did it right and not a drop in 5 + years. I let it sit overnight before refilling the fluids

 

[jazak5]

Hey guys need some help. I'm working on a 1970 340 Cuda. The engine is built to bracket race and is really quick. It has a Trimec 5 spd and aftermarket Bell housing (scatter shield type). The existing oil pan (8 qt) had pin holes and leaked significantly. The gauge indicates I'm pushing 100 PSI oil pressure on acceleration .



I pulled the pan and replaced it with a stock replacement (5 qt), from Summit along with a gasket kit. I installed and it still leaks at the ends where the pan is curved in a ½ circle. I removed the pan again and I got racing gaskets from Mancinni, Racing and replaced the cheaper set. The distance between the bell housing and oil pump makes for a really tight fit with the pan and gasket slightly wider than the opening. I trimmed the pan but still had to force the pan and gasket into place. I took it for a short run 15-20 minutes and it still leaks. I get a 3-5 inch puddle under the car and its coming from both the front and rear seal where its curved.

Anyone had this problem and if so did you find a fix?

Is the replacement pan just too cheap to make a good seal?

Classic industries has a replacement pan stamped 294 – would that be better?

Am I better off getting an original used pan?

Do I just need to get use to a leaky pan?

Any help is appreciated. I’m very frustrated at this point and not sure what to try next.

Thanks

View attachment 1716423470

View attachment 1716423471

oil pan leak

Now that I sealed the rear China wall leak, I see oil at the front of the engine. 360 magnum, '67 dart 2dr hardtop, slant six K frame with Schumacher conversion motor mounts. After some testing, checking, it appears that my oil pan is leaking at the front corners. I put a "diagnostic diaper"...

www.forabodiesonly.com

https://images.carid.com/permatex/items/82099.jpg?_gl=1*122407x*_gcl_aw*R0NMLjE3NTExNjIwNTQuQ2owS0NRand3TzIwQmhDSkFSSXNBQW5USVZSUXJ6RTlDMnlwSTF6VXBfNFo2M2ZVZGRnczdoWFRvbHQ2VndEeGdZaVIwODlWY21id2pDb2FBbVpCRUFMd193Y0I.*_gcl_dc*R0NMLjE3NTExNjIwNTQuQ2owS0NRand3TzIwQmhDSkFSSXNBQW5USVZSUXJ6RTlDMnlwSTF6VXBfNFo2M2ZVZGRnczdoWFRvbHQ2VndEeGdZaVIwODlWY21id2pDb2FBbVpCRUFMd193Y0I.*_gcl_au*NTg2NDkxMjMxLjE3NTExNjIwNTM.*_ga*MTk1OTY0NDQ2MC4xNzUxMTYyMDU0*_ga_V12BPQ778M*czE3NTExNjIwNTMkbzEkZzAkdDE3NTExNjIwNTQkajU5JGwwJGgw

 

[MV8]

Replace the pan again. If it is wider than stock at the rear main, do not cut the lip off the pan. If it is slightly too wide, the pan can be narrowed to stock width at the rear main.

Put the pan upside down on a flat wood surface, screw a 6-8 inch piece of 2x4 into the surface, then another on top of that to support the full half moon of the pan, then tap with a small hammer on the rear lip so it will match the old, pin-holed pan.

 

[RustyRatRod]

Pull the pan. Remove all of the gaskets. Clean the pan and block 100% SPOTLESS. Run a bead of Right Stuff in the groove in the timing cover and main cap tall enough the pan will squish it down when installed. Run a bead down each side of the pan so the beads will come together in all four corners and install the pan. Say goodbye to leaks.

 

[340six]

Pull the pan. Remove all of the gaskets. Clean the pan and block 100% SPOTLESS. Run a bead of Right Stuff in the groove in the timing cover and main cap tall enough the pan will squish it down when installed. Run a bead down each side of the pan so the beads will come together in all four corners and install the pan. Say goodbye to leaks.

I agree. And a plus on the cleaning.
Only time this method did not work it was a new in box Mopar 318-340 Mopar Performance part made in a For-In land that was stamped bad. Was bent cross ways.
So would leak out front corner or if that sealed the opposite side in back.
Thank God we did it at a friend's placed who has a lift as he is a transmission man. We tossed the pan. Then got a dented up old pan ball peined the holes back flat on rails. Beat the few floor jack or road dents out. Sealed up first try.
New is the new bad.

 

[Dartman61]

Thanks for all the advice. I pulled the pan again and rear 1/2 moon gasket was torn, I ordered a different gasket set for older small block. 1/2 moon gaskets were different. Rear gasket was not as wide so fit with little interference between bell housing plate and oil pump. seemed to fit up nicely. I got it from Mancini Part # 2581 for Chry 273-360 MP-15. This is the 3rd set of gaskets and finally one that fits - I have sealant setting and will fire up tomorrow. Fingers crossed

 

[Dartman61]

Well sorry to say that didn't do it. After start up and warm up period I noticed leaking at the rear passenger side of the pan - not a lot but with the blue light and dye in oil you could see it. After an hour of driving the same rear corner seal blew out and I lost a quart on the driveway - fortunately I'd just pulled into home. I've started and maneuvered the car without further leaking, very short run time. Now I'm starting to question my oil pump. The gage tells me its putting out 110 PSI at max and cruses around 80-85 psi. My 440 in my Dart (425 HP) with high performance oil pump only puts out 65-70 psi and never spikes. Can anyone tell me what I should be expecting am I fighting a pump thats putting out to much PSI or do I just need to do a better job of install and sealing? In short HELP!

 

[Inertia]

I'll toss this out there.
I have experienced a hole worn into the back of the pan, where there is interference with the H/V pumps .
Look for interference/shiny spot inside back of pan.

Next time you do it, remove trans tin shield, . . - - I know, starter etc, but . . .

 

[Dartman61]

Okay I finally fixed it - as you might expect we had multiple issues. First I bought a oil pan from Summit - it didn't fit well and was not very sturdy. I replaced with an 294 Mancini replica (stock pan) that was stronger and better fit. Beyond that I found that the PVC valve was not connected to the carb ( closed all the time) and allowed pressure build up so I connected that. I replaced the high flow oil pump with a Melling standard M72 . Even with these changes the pressure was to great for the seals. I swapped out the 20W50 the owner was recommended to a 10W30 and every thing changed. The pressure at Idle dropped to 40 psi and under acceleration reached 65 PSI well within the seal parameters. Its been on several extended runs and no leaks or issues.

 

[Inertia]

Thanks for reporting back, good job.

Wishing you lotsa miles with lotsa smiles, cheers .