still leaking

[mikleins29]

Well 2 rear main seals later staggering the gaps this time and now it is dumping out at a constant stream not drip very discouraged buying another seal and redoing it again this Thursday don't know if there's a big difference in manufacturers seals with material but I am trying a felpro this time not a national. Any thoughts guys?

 

[Jeff73Mach1]

Well I would get it real clean, but I would also drop the rear main cap and check the bearing for wear. If the bearings are worn and allowing crankshaft wobble, the seal replacement is a temporary fix. And it is possible to put a mainseal in facing the wrong way. The "lips" of the seal that touch the crank should face into the engine. Make sure and lube the seal before use to prevent galling of the rubber.

 

[Wolverine]

Well 2 rear main seals later staggering the gaps this time and now it is dumping out at a constant stream not drip very discouraged buying another seal and redoing it again this Thursday don't know if there's a big difference in manufacturers seals with material but I am trying a felpro this time not a national. Any thoughts guys?

Had to do a rear axle seal 6 times before it sealed up properly...not as bad as your issue, but certainly as frustrating. I have never used anything but a NATIONAL seal.

I would try to get a micrometer on the crankshaft and make sure it is in spec for your seal. For example, your seal should list a crankshaft diameter of 2.000 to 2.040(not the actual numbers...just an example). Measure your crankshaft to make sure it is within the spec.

It is a little difficult to measure the seal diameter because it is rubbery...but if you can fit it onto a cone, and then measure the diameter at the cone, you can make sure it is within spec as well. Don't ask me where to get a cone...probably the art store.

 

[droptop73]

A dab of sealant between the ends of the seal halves help too.

 

[TommyK]

Are you trimming the seal to set the proper seal crush?

.010-.020

 

[marks73]

+1 on checking those bearings! For what it takes while you have the pan off. Great insurance. Pay particular attention to your thrust bearing and be sure to do it by the book.

 

[Darkhorse71]

If you are building up a lot of crank case pressure ie blowby from worn rings or high RPMs, and it isn't vented by pvc, vacuum pump or breathers, it will greatly accelerate a seal problem.