Rear axle oil seals - which way is out?

[CanberraBJ8]

Need to replace the seals in my rear hubs as they have been leaking - a lot. A friend said that he'd bet the currently installed ones were in the wrong way around... Its hard to see in the photo, but can anyone tell?


Which side is this on the replacement? this the side that faces towards the diff - or out?



Thanks

oh, and the best way to pull the bearing out of the hub/ and replace it?

Cheers
Simon

 

[steveg]

Your picture shows the inner side of the seal.

 

[BoyRacer]

Your first photo ... It's hard to tell, but is the seal still in the hub? If it is, it is in backwards.

 

[Bob_Spidell]

As a rule, the side with the spring should face the oil or grease you're trying to contain.

Best to press the bearing out with a hydraulic press and suitable drift (large sockets with same outer dia. as the outer bearing race work well).

 

[CanberraBJ8]

Just had a careful look at my hubs, and furnished with the info you've all given me I can confirm they are in backwards. Glad this is so, as they are still in good nick, so I was wondering why they should be leaking!

If I'm pressing the bearings out, does this mean that the bearings are not re-useable? There is no way I can see that you can press them out touching only the outer sleeve as its obscured by the hub? Putting them in using the outer sleeve makes sense.

If you were using the manual to guide you when working out which way the seal goes back in, you could be excused for getting it wrong...

 

[Bob_Spidell]

...

If I'm pressing the bearings out, does this mean that the bearings are not re-useable? There is no way I can see that you can press them out touching only the outer sleeve as its obscured by the hub? Putting them in using the outer sleeve makes sense.

Good question. I think most people plan on replacing anyway. My guess would be that you could press them out using the inner race, as you wouldn't be rotating the bearing and, being hardened steel designed to take a significant load they would be fine. When they're out, check them carefully for smoothness and no heat discoloration. If they have a 100K miles or more I'd probably replace them on principle.

 

[steveg]

If the seals leak and are the correct size, likely the bearings are worn.

I remember tapping the bearing out with my knockoff hammer, supporting the stud side on the garage floor with a PVC pipe fitting (ID larger than bearing OD) and seating a socket in the center of the bearing. It came out relatively easily. A bearing-house guy told me to check for two things: roughness and zero ability to rock the bearing hub back and forth on its axis relative to the outer ring. Check the manual for the amount the bearing needs to be proud of the carrier.

 

[CanberraBJ8]

Thanks Bob and Steve.

The bearings look pristine - the car was restored in about 2000 so I'd be surprised if they have more than 5000 miles on them. It was just that the seals were leaking, and given they are in the wrong way around I guess they are excused for that...

I'll try giving them an exploratory tap...

 

[jsfbond]

Make sure the rear end vent is clear, pressure can build to the point of making new seals leak or blow out.

 

[CanberraBJ8]

Thanks jsfbond

Do you mean the breather on the top of the axle case?

 

[CanberraBJ8]

I dropped the axle off to the diff guy yesterday. Interestingly he said the seals were in the hubs the right way around... Steveg, did I mis-understand "inner side"? Inner being the inner side of the hub, or the inner side of the car? That is to say, according to the diff guy yesterday, the spring side of the seal should face outwards away from the vehicle...

He seemed to think that the seal wasn't to blame for the oil leak - unless it was leaking due to the axle surface not being polished to a smooth enough degree (so the seal made good contact).

As for the health of the diff... we'll see next week (and that will decide my option of the 3.54 ratio diff being discussed on the other thread...).

 

[PAUL161]

The spring side of the seal faces the differential, the pressure side, the smooth side faces the brakes/drum. Reason, the more pressure of oil on the seal theoretically tightens the rubber on the axle surface. When you pull the old seals, trash them and put new in, don't just turn them around as they will be distorted. PJ

 

[CanberraBJ8]

Sorry guys, I'm confused. The oil contacts the seal from the wheel side, not the Differential side, surely? - out through the axle case, through the space/distance piece, and back into the bearings. And the seal stops the oil from continuing out of the hub inner opening and then filling your drum casing...

 

[Bob_Spidell]

Yep. The spring side of the seal faces the source of the oil, in this case the bearing.

 

[pan]

Sorry Paul161, Bob Spidell & CanberraBJ8 are right, and so is the workshop manual illustration. The side of the seal with the tensioning spring visible should face the lubricant. In the case of the rear hub seal, that is facing out, away from the differential. When the seal is positioned in the hub the blank side of the seal is visible prior to installing the hub on the axle journal.

 

[PAUL161]

My bad! I thought the lube was on the other side. Sorry. PJ

 

[Brinkerhoff]

Yes the spring on the seal faces the bearing and outward when fitted to the axle. The bearing needs to fit the stub of the axle with some interference when fitted and not slide on or off easily or the hub assy. will rock and not seal oil also. Kevin

 

[CanberraBJ8]

There seems to be seals, and seals... My diff guy is chasing NOK seals - I'd purchased seals from the local Healey parts supplier and they are NAK... apparently there are any number of variations. NOK, KOK etc. Have any of you come across all of these? Results? Mick (the diff guy) is chasing NOK or CS seals.

 

[steveg]

The seals on Healeys all seem to be basic fractional inch sizes. If you measure any seal you'll see it will be something like 2-1/4" or 2-3/8" and not, say, 2.30"
Any seal of the right dimensions will do. These NAK seals and bearings are just the Chinese or Korean ones Moss is buying. The dimensions are marked on the periphery.
As a generalization - when you measure things on the car, the designers never seem to use an odd size when they can use a "normal" quarter or eighth-inch size.