bought a 350 4 bolt main to put in my trans am and want to change all gaskets in it before i drop it in the car. the only thing i need help with is the rear main seal. what is the easiest way and what the the tq specs for the cap when i put it back on.

 

To change it, you'll hafta undo all 5 caps. Torque spec for stock bolts with oil on the threads is like 65 ft-lbs. If it's 4-bolt-main, the outer bolts get about 55 -60 ft-lbs.

 

why would he have to undo all 5 caps? i've never heard of that.

2 piece rear main seal - remove rear cap, remove the seals, insert new seals with rtv on the ends, install rear cap. Main caps are 80 foot lbs, rear main is 120-150 INCH lbs. i like to offset the main seals 1/4" from the mating surface.

1 piece rear main seal - remove rear seal, install new rear seal.

 

QuickStyle is correct, except that 9 times out of ten, you can't replace the in-the-block half of the 2-piece seal without lifting the crank away, and you can't do that without loosening all the caps. Maybe QuickStyle is one who doesn't glue the seals into position. I also glue the ends.

 

ok, i see what you are saying now. i have in the past had trouble removing the in the block half of the seal, it requires a bit more work to get out. what i do for that is use the bottom half of the seal and push the in the block seal through with it and get both seals half way meeting on the top of the crankshaft, then you should be able to pull both seals out with some pliers. by removing the other remaining caps i can see it making the job easier, i guess just sometimes you get lucky and only have to remove the rear cap.

 

GM didn't glue them, and I like that tip about getting both ends on top, thanks.

 

If you purchased a higher mileage used engine, you will definitly want to inspect the crankshaft hub that the rear main seal seals to. Higer mileage engines will often have a groove worn into the crank hub where the rear main seal lip makes contact, causing the seal to fit less snugly. If you replace the rear main seal and do not fix a grooved crank hub (if you have one), your engine will most lkely still continue to leak. If you have a grooved crank hub, look for a crankshaft sleeve, its an easy fix and works real well at sealing the rear main.