I have had this problem before......
The problem is that the rear wheel bearing has been spinning on
the machined surface that is part of the rear axle housing. It is not
supposed to spin, it is supposed to be a press fit, and be held in place
by the 120+ footpounds of torque that holds the hub nut in place. The
book says to weld on material and remachine to spec, but I don't know how
to do that without taking the entire differential housing out of the car,
stripping it, and finding a machine shop that has the proper equipment.
You would have better luck buying a good used housing, and replacing it,
(a big job).
Or.............Try this:
The goal is to reduce the clearance between the inner surface of the
bearing and the machined surface to the point that it is once again a
press fit.
1. Buy a new bearing. Pack it with grease, before you install it. That
will help extend its life. You want to reduce the clearance between the
bearing and the machined surface as much as possible, and the old bearing
is going to have some wear on its inner surface.
2. At this point, if it takes some effort to push the bearing onto the
housing by hand, then go to the auto parts store and buy a tube of
Loctite Bearing locker. Apply liberally to the machined surface and the
inner surface of the bearing and install the bearing. Tighten the nut to
at least 120 ft.lbs. (Use a torque wrench) Allow the Loctite time to set
up.
3. If the bearing still slides on and off by hand, and takes little
effort to make the inner surface spin by hand, then take a sharp small
chisel, and carefully, and uniformly, rough up the machined surface by
taking the chisel and hammer, and make tiny nicks in the surface. Think
of it as trying to apply a knurled surface by raising the metal up from
the worn surface. When you do this, apply the "nicks" in a set pattern,
all the way around, trying to make the surface as uniform as possible.
Don't make the nicks any bigger than you have to. You can always add a
few more deeper nicks later, if needed.
When you get it to the point that the bearing needs to be tapped on with
a hammer, then do step number two above, and you are done.
I have done this successfully a number of times. The only drawback is
that if you ever have to replace that bearing again, it may not work a
second time. So, if you plan to keep the car, be on the lookout for a
good used differential housing and put it up in the garage rafters, just
in case.
Good Luck!
Randy Kegg .
On Tue, 4 Aug 1998 21:21:26 EDT Wildbil923@aol.com writes:
>In removing the rear hubs on my MGA, I found that the left rear hub
>was very
>loose on the machined surface of the axle tube housing. Apparently
>the nut
>securing the hub had never been tightened correctly at the factory.
>(A little
>too late for a warranty claim!) I know this because the car has been
>in the
>family since new and the rear hubs have never been off. Anyway, one
>of my
>books warns about the hazards of not tightening this nut up
>sufficiently and
>indicates the result will be wear on the machined surface and a loose
>fit with
>the bearing. The book further warns that a loose fit here can put a
>strain on
>the axle half shaft and can cause it to break. My MGA has well over
>135,000
>miles on it with a loose securing nut and the axle has never broke,
>but I can
>understand a loose fit here could put a strain on the axle half shaft
>and
>could cause it to snap. The book says the axle tube should be welded
>oversize
>and machined down to spec.
>
>At this point, I'm inclined to reassemble the thing as is and give a
>good
>tightening to the securing nut. Seems like this should hold everything
>reasonably in place, but I'd like the wisdom of the list. The bearing
>slips
>on and off by hand, but there does not appear to be so much slop that
>it rocks
>back and forth.
>
>Anyway, my question: Has anyone had experience with this problem and
>has
>anyone found solutions other than the weld-up-machine-down route?
>
>TIA for all help!
>
>Bill Wilkman
>1960 MGA
>1960 AH Sprite
>1961 AH 3000 BT7
>
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