What is it with the seals?
Thread Starter
Le Mans Master
Joined: Oct 2003
Posts: 7,625
Likes: 4
From: Director of Bands
St. Jude Donor '08
What is it with the seals?
I have read more threads about rear seals (etc.) leaking... even new ones after an install. What is it with these seals? Why are they so prone to leakage? Are they made of glass or something?
Drifting
Joined: Jan 2005
Posts: 1,354
Likes: 325
From: San Antonio Tx
From my experience, Tap it in carefully with a hammer and it will still leak. Press it in ( I used a short piece of 4" PVC, longer bolts and the flywheel to press the seal in) no more leaks.
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
Most times it's incorrect installation that causes them to leak.
First, the seal should be oiled to minimize the friction created during installation.
Second, it must be centered and installed straight; not leveraged in.
Third, there should be no burrs present in the block.
Fourth, they should be installed a very little at a time, preferably with hand pressure only.
Two piece seals must:
First be oriented correctly,
Second, oiled
Third, applied with as little turing movement as possible; straight down is preferable. If changing the seal with the engine in the car, you'll need to use a shoe-horn installation gizmo to prevent cutting the seal as it's rotated into the block.
Fourth seal parting line NOT aligned with rear main cap parting line
Fifth, silicone sealant applied to the ends; both the cap and seal ends
Line bored 400 blocks call for a different two piece rear main seal (or you can use the old zip-tie method) to take up the additiional clearance.
For both types, the bolts must be cross-tightened, at little at a time, which equalizes crush.
This is how I attack the problem.
Jake
First, the seal should be oiled to minimize the friction created during installation.
Second, it must be centered and installed straight; not leveraged in.
Third, there should be no burrs present in the block.
Fourth, they should be installed a very little at a time, preferably with hand pressure only.
Two piece seals must:
First be oriented correctly,
Second, oiled
Third, applied with as little turing movement as possible; straight down is preferable. If changing the seal with the engine in the car, you'll need to use a shoe-horn installation gizmo to prevent cutting the seal as it's rotated into the block.
Fourth seal parting line NOT aligned with rear main cap parting line
Fifth, silicone sealant applied to the ends; both the cap and seal ends
Line bored 400 blocks call for a different two piece rear main seal (or you can use the old zip-tie method) to take up the additiional clearance.
For both types, the bolts must be cross-tightened, at little at a time, which equalizes crush.
This is how I attack the problem.
Jake
