Front bearing inner oil seal install question

[frag]

I'll be doing my front axles in a day or two.

I already have all parts needed and hopefuly all tools.

Only one thing is still bugging me. I decided to replace the wheel bearing inner seals since it's the one that's most often responsible for bearing failure. I'm not touching the hub nor the bearing though.

I have this seal in front of me. It's LARGE, approx. 2 1!2 inches across with a very narrow crown.

First question. Aside from the hub tamer, what kind of tool should I use to install it without damaging it?

 

Second question: I have Subaru ramaned axles and the part of them that will be turning inside the seal's lip is painted green!!!

I was expecting this part ot the axle to be of a mirror like metal finish. Is it standard for Legacy's remaned axles to be prepared that way?

The guy where I bought them told me to sand this part lightly with ultra fine emeri paper but not to the bare metal.

 

Last question: is it necessary to pack some grease in there (remember I'm not removing the hub nor the bearing) to insure a constant supply of lubricant to the seal's lip?

 

Thanks in advance for all inputs.

[SevenSisters]

A seal installer would be nice but I've just used a block of wood to distribute the force over the whole circumference of the seal and tapped them into place with a hammer.

 

My original seals most likely failed because of rust formation on the axle which in turn chewed up the seal.

I have not seen a Subaru half shaft but remember thinking how nice it would be if the sealing surface of the axle was coated with teflon to aid lubricity and prevent rust. Maybe that's what it is. Does it feel slippery? A lot of PTFE coatings are green, but this may just be some Subaru color coding scheme.

 

If the coating is smooth though, I wouldn't sand it off.

[alias20035]

Originally posted by SevenSisters

A seal installer would be nice but I've just used a block of wood to distribute the force over the whole circumference of the seal and tapped them into place with a hammer.

 

My original seals most likely failed because of rust formation on the axle which in turn chewed up the seal.

I have not seen a Subaru half shaft but remember thinking how nice it would be if the sealing surface of the axle was coated with teflon to aid lubricity and prevent rust. Maybe that's what it is. Does it feel slippery? A lot of PTFE coatings are green, but this may just be some Subaru color coding scheme.

 

If the coating is smooth though, I wouldn't sand it off.

 

Agreed on the Teflon coating! Don't sand it off.

 

As for seal installation I find that the old bearing race is the identical size of the seal and therefore it works very well to push the new seal into place. Sometimes the wood block trick is required to get the seal started. The metal race will NOT damage the seal as the force is distributed evenly around the seal, only if you apply pressure to one area of the seal will it be damaged.

 

Be sure to install the seal in the correct orientation, note the installation of the original one! In fact I recommend marking the original seal with a paint marker (yellow or other bright color) along with the knuckle before removal. With the yellow mark on both the old seal and knuckle you will have a reference to go back to. I get in the habit of doing this with most parts that come off of the car, since after many hours and cups of coffee it is easy to forget how things go back together. I once reattached a transmission and engine, went back to the parts table and only then did I spot the release bearing that I forgot to put in.

[avk]

I believe the seal inserts into its bore from the axle side and the CV housing itself is what holds it in place. Not sure what the green coating is made of, but inner joint housings have it too. My guess would be paint.

[frag]

Thanks for your replies.

1) The green coating is paint. It's the same stuff and same color as is applied to both cv joints housings at each end of the axle. It chips rather easily and as far as I can see, there's a very smooth melal finish underneath the paint where the axle meets the seals.

Probably just to prevent the part from rusting on the shelf. On one axle this paint is mirror smooth. I think I'll leave it be ahd let the seal lip slowly make it's way to the smooth metal underneath. On the other, the finish is a little rougher and I think I will give it a light once over with ultra fine emery paper.

 

2) Since I'm not removing the bearing I will not be able to use the bearing race to insert the seal. I think I will use a wood block like Seven Sisters suggests.

3) Anybody has an opinion on what I should do to keep the seal/axle joint lubricated? If none I will try to pack synthetic grease (more water repellent than standard) BEHIND the seal and hope for the best.

Thanks again for your inputs.