Rebuilding 428 Ventura Engine


New member
I have a '67 Pontiac Ventura with a 428 engine. The rear main-seal is leaking. I plan on replacing the seal. The question is: Do I replace it through the oil pan/crank or split the tranny from the engine and remove the flywheel? Can anyone please help?


Staff member
i have heard of people doing it thru the oil pan but you would have to search for a write up of the specific steps involved. I believe it involves using a hooked tool sort of like a dental pick and rotating the crankshaft. If I find it I will post it here. Did some further research, if you want to do this only once, you got to pull the trani. Seems this is the hottest new seal technology
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New member
HI,to replace the seal, you will have to remove oil pan drop, rear main cap, fish the rope seal out and install a new one. it takes a special tool to remove and install rope seal. There is a two piece seal out it is a viton seal they're about 40 bucks. its like a chevy seal, should be easier to may be better off to pull engine to get oil pan off. you have to jack engine up so far on a pontiac to get it off. Good luck on your project.