Pinion Seal Questions

[HealeyRick]

Just replaced a leaky pinion seal (BJ7 rear end) and it's still leaking. What did I do wrong? I packed the area around the spring with vaseline so it wouldn't pop off and coated the inside lip with oil. I also coated the outside rim of the seal with hylomar. I installed the seal with the spring side facing the rear of the car and drove it in until it bottomed out, approximately 1/8" from the edge of the housing. It looks like it's leaking at the bottom edge between the outer edge of the seal and the housing.

1. Did I install the seal correctly or should the spring face toward the front of the car?

2 Should I have not driven the seal in until it bottomed out and only driven it flush with the housing?

There's no scores or scrapes in the seal housing, so if it isn't one of these two things, what else should I look at?

Thanks.

 

[Keoke]

Sounds like it was reversed to me Rick. But get a new one and use heavy grease in the spring side no vaseline.

 

[Bob_Spidell]

2 Should I have not driven the seal in until it bottomed out and only driven it flush with the housing?

Yes and no. The extended end of the diff housing--the end of the 'cone'--has about a 1/8", 45deg chamfer on the inside at the end. You should drive the seal in until its outer edge is even with the inside edge of the chamfer (use a large socket for a drift to get the seal 'square'). Your seal is not riding on the machined part of the yoke, or it's riding on the very end (hold the yoke up next to the housing at its approximate installed location, and imagine where the seal would ride on it). Otherwise, you did everything correct.

Don't feel too bad, I did this once myself. Unfortunately, you'll probably destroy the seal getting it out, so you'll need a new one. Check the yoke where the seal rides, it should be OK but check to be sure.

BTW, the chamfer is otherwise unnecessary as far as I can tell; I think it's reasonable to assume it's there mostly to assist correct fitting of the seal.

 

[HealeyRick]

Still confused on the seal installation. This is a similar seal.

Side A:

Flat across face

Side B

Recessed with spring around the opening.


Which side faces to the rear of the car?

 

[Bob_Spidell]

Side B. You had it right (don't think the vaseline is necessary, though).

 

[Ed_K]

Hi Rick,

Side B goes toward the rear of the car...

Check the surface of the yoke shaft where the seal rubs on when the yoke is installed. The yoke surface can be scored / rough and may need to be smoothed with very fine sandpaper or steel wool.
If it cannot be smoothed up, then a ready sleeve can be slid over the yoke shaft to put a new / smooth surface up against the new seal. A slightly larger size seal will need to be used with the ready sleeve. I have not had to use any ready sleeves but they should be available at local auto parts stores.

Ed

 

[HealeyRick]

Thanks guys, I'll give it another go. I thought I had the seal in right, but was beginning to doubt myself.

 

[Ed_K]

One more thing I remembered..
It has been a while since I did this but I think you should put a dab of sealer onto the threads about where the nut will end up. I think I put a dab onto the bottom of the washer as well. Someone advised me at the time that they can leak around the threads. Mine did not leak after I replaced my seal. But once I fixed the big leak, I discovered that it was also leaking around the four bottom nuts that hold the pumpkin into the housing. I just loosened them up and added sealer and then retightened them. That fixed the rest of the leaks.

 

[HealeyRick]

Finally got it all buttoned up with no leaks. For future reference, the bearing retainer from a Ford T5 tranny, makes a perfect seal driver. Good thing I just happened to have a spare one around. Thanks for all your help, it's always great to have so much help at the tips of your fingers.