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MG MGB Technical - rear wheel bearings

hi
need to replace the thrust washers in my diff and will change the wheel bearings at the same time. Is there anything particular i need to look out for, or is likely to be a major problem?
gary
G Roberts

Assuming wire wheels

Not too bad but important to get the right tools to get 'em out and take them to someone with a press to take bearings off shaft and get bearings back on the shaft.

- 2 or 3 claw eight or ten inch puller with center screw to get the hub off
- impact slide puller to get the shaft out (I got loaner from auto parts store but don't know what's easiest in the U.K.)

The nut in the shaft has pin and there is hole in the shaft to reach it which is usually covered with grease.

Use correct torque putting nut back on - - 150 lbs. Had to stand on mine.
J.T. Bamford

I went through this a couple of winters ago, working in a friend's woodstove-heated shop. I set the new wheel bearings on top of the woodstove for a couple of minutes, and they slid onto the shafts with nothing more than finger pressure.
I also don't recall much difficulty getting the hub or axle out - put the brake drum back on the axle with the nut screwed back on a few turns and was able to slide it against the nut to urge the axle out. I'm sure there are more detailed descriptions in the archives.
All in all, it can be done with no special tools.
Doug
D. Fischerr

I agree with D. on this one. I was going to say something before but I was afraid of getting stepped on for being such a Primitve Pete. You can whack the old bearing off with a good size hammer. It's no good anyway. Putting the new one on takes a little more care. Use a big punch or something to direct the force to the inside of the bearing where it meets the shaft as you tap it into place. The idea about warming the bearing up a bit before putting it on is a good one.
Dana Wilson

Watch out, the new Moss bearing that thay supplly are junk!!!! Make sure the new bearing is R.H.P., this bearing will go a long way. I have run the rhp bearing 300,000 miles on my 4 cyl. & thay are just fine & still going. On my V-8s I have to change them around every 100,000 miles because I pull a trailer that weights 3,000 lbs all over the east 1/2 of the U.S. & I drive the car HARD. If there was no noise out of the bearing & thay look good I would use them over, I ck. all the bearings that come out of a B rear that I am changing to the 3.07 V-8 gears & I don't think I have seen a bad one. The new moss bearing is made in japan???? I think & it has 1 extra ball & it MIGHT go 10,000 miles, in a V-8. We make up a stainless steel thrust washer & toss the fiber washer away.
Glenn Towery

"Watch out, the new Moss bearing that they supply are junk!!!!"
Sheesh. That's just what I want to hear. I ordered a new rear axle bearing from Moss yesterday.
Dana Wilson

I realize it's a little late, but for the record - the rear wheel bearing is one part I was able to buy over the counter at the local import parts store. They didn't even have to call into the warehouse for it.

BTW, to get my axle out of the housing, I got a junk brake drum, mounted it back on the hub and hammered it outward. I did have a shop change the bearing. They were surprised at the force required.

I'm no metalurgist, so I wonder if heating the bearing on a stove and letting it cool slowly would anneal the balls or race - making the bearing wear faster?

Matt Kulka

I've found the best way to heat a part for assembly is to place it in a pot of hot motor oil. Learned this trick when rebuilding an Alfa 5 speed that I tore up.
R. L Carleen

Actually, I forgot that when the guy went to put the new bearing on the shaft the force was picking the press up and he coudn't find the press fitting to make it work against itself so......he looked around, found 2 foot piece of pipe that was bigger than the shaft and smaller than the bearing and using it pressed up against the bearing, pounded (shall I say "slammed"?)the pipe against the concrete garage floor, sliding the bearing on. So all in all, next time, guess I'll just do it all myself. Nice to know you can just buy 'em locally.

JTB
J.T. Bamford

Bearings have a number on them which can be referenced by a bearing supplier. You can then buy top brands like Timken or Fag. There are bearing suppliers in every major town and some not-so-major ones, too.
Charles Edwards

Perhaps here is a good point to mention
lubrication. While the Diff is lubricated by
EP90 gear oil it has been my experience that
very little of this gets to the side shaft
bearings. In fact both Bentley and Haynes advise
against over filling the diff for fear of oil
leaking past the drive shaft seals and contaminating
the brakes. Both Bentley and Haynes do not
have any specific lubrication indicated under the Lube
sections of the manuals but in the 'Reassembly'
sections advise 'Pack the bearing with a suitable
grease....' I assume that this should be wheel bearing
grease. As there is not a cavity space problem as
with the front wheel bearings the side shaft bearings
can be 'Well packed' Also ensure that the new seal
and collar are lubricated as a dry contact can tear
the new seal.
Len

While we're on the subject of lubrication, don't forget to check the vent on the axle. If this is blocked, the oil in the diff will be pushed out as it warms up. The brake linings will suffer!

Mike
Mike

Mike:

Where is "the vent on the axle"?
Boris

The vent I believe is a small little plastic cap and tube style sytem on the top of the diff housing, if I recall rightly. But like Charles said, if you look for the bearing number on the bearing, you should be able to purchase one at a bearing dealer, which in a lot of cases will be for less money than at an auto parts store. I've done this on other vehicles of mine, for both axles and transmissions.
Anthony Morgan

Right, Anthony, on the banjo axle at least, the vent sits on top of the diff housing a few inches away from the centre line of the car, towards the fuel pump. It is a bit of pipe half an inch long and about 1/4" diameter with a plastic cap on the top.

Mine was blocked so I removed the cap and prodded the debris through with a tooth pick. This reduced the leakage but I still had to change the pinion seal.

Mike
Mike

On a tube axle it is on top of the half-shaft tube just to the right of the diff casing.
Paul Hunt

This thread was discussed between 23/06/2003 and 01/07/2003

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