• When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

Rear Main Seals

Al W

New Member
Local time
6:35 AM
Joined
Mar 10, 2014
Messages
4
Reaction score
0
Location
Albany NY
What is the best seal to use for a R.B. big block?
 
I use the OEM seal retainer, and the seals from the Fel-Pro gasket sets. Have not had an issue yet with leaking.
 
I've used the Mancini Racing seals and the stock seal retainer.

If you have studded main bearings make sure the back ones don't hold the pan off the gasket. I've had to shorten the left rear stud on 2 different engines ( I was using custom pans: one Milodon and one Chinese). The blocks weren't drilled deep enough.

Bryand
 
I just installed both of these...

mancini-racing-billet-rear-main-seal-retainer-31.gif




mancini-racing-viton-rear-main-seal-kit-5.gif
 
I've used the Mancini Racing seals and the stock seal retainer.

If you have studded main bearings make sure the back ones don't hold the pan off the gasket. I've had to shorten the left rear stud on 2 different engines ( I was using custom pans: one Milodon and one Chinese). The blocks weren't drilled deep enough.

Bryand

Had the same issue. I ground reliefs in my retainer to clear the studs. Found out the hard way and had to tear the pan and windage tray back off mid install and relieve the retainer. Boy was I REAL HAPPY about that haha. :mad::D
 
It is also important to "offset" the 2-piece style rear main seals slightly so that the edges don't align directly with the spot where the block & rear main seal retainer come together + add a drop of adhesive to the edges of the seal halves.
 
Interesting. Have you, or anyone here, installed that type of seal?
I haven't used this seal yet, but I will next time around. For one reason only. The factory style seal won't hold crankcase vacuum. The red seal never leaks when installed correctly.
Doug
 
Auto Transport Service
Back
Top