rear main seal question

[orangecrush]

1968 340 - the Fel-Pro kit has a rear main seal that has block half as half circle and cap half is half circle with "ears". Book shows both halves as half circles and ears ar separate, allowing for the "offset" placement of the seal (which is a better seal - so they say) Two questions - is this one fine and 2) Will a 360 seal (which I know comes in the two half-circles) fit my 340 crank ?

 

[mguner]

360 has larger main bearing diameter....

 

[mullinax95]

Post deleted

 

[340sFastback]

I put that same Felpro rear main seal in my 340 years ago. Still does not leak a drop. Make sure you clean the block and rear main mating surfaces with Brake Parts Cleaner and clean paper towels. Keep cleaning until its 100% oil and dirt free. Then apply a thin layer of sealer between the two. It will leak if you don't use sealer on an oil free surface. Lip of seal faces in and make sure seal has a small film of oil on it so its not dry the first time the crank turns. And don't worry about leaving the ears in place and not being able to rotate it. It will seal up as is.

 

[340sFastback]

360 has larger main bearing diameter....

Agree.

 

[mullinax95]

I put that same Felpro rear main seal in my 340 years ago. Still does not leak a drop. Make sure you clean the block and rear main mating surfaces with Brake Parts Cleaner and clean paper towels. Keep cleaning until its 100% oil and dirt free. Then apply a thin layer of sealer between the two. It will leak if you don't use sealer on an oil free surface. Lip of seal faces in and make sure seal has a small film of oil on it so its not dry the first time the crank turns. And don't worry about leaving the ears in place and not being able to rotate it. It will seal up as is.

What seal are we talking about? The oil pan seals?

 

[mguner]

I might not know what I'm talking about but the 273,318,340 use the larger rear seal and the 360 uses the smaller one. Both seals have ears but are smaller on the 360. Use the one that fits your oil pan the best... it should be the larger seal that wraps around the pan on the 340.

He was talking about the crankshaft seal not pan seal. Remember.... to make a 349 (318 stroker) you have to turn down the 360 mains to fit the 318 block.

 

[orangecrush]

Thanks guys.