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MG Midget and Sprite Technical - hub seal

hi all.
oil dripping out of rear brake drum, am i right in assuming that its the half shaft o ring and gasket and not the hub seal.?
thanks bob.
bob taylor

I would say that if you haven't recently had the wheels off or done anything to the brakes then its likely the hub seal.
But if you have done any of those things then it possible you disturbed the gasket seal and its coming from there.

I would buy one of each to have at hand for when you have a look...

Not expensive .

Have you heard any extra noise from the rear? looking on the pessimistic side could your bearing have collapsed....
Andy Phillips (frankenfrog)

Bob
Usually if it is running down the backplate it is the seal. A leaking hub gasket is usually evidenced by oil dripping out of the brake drum.
Alan
Alan Anstead

thanks alan, yes its running down the backplate.
bob taylor

As the backplate has been mentioned (slight thread drift here), I've recently beeen trying to remove the backplates from the axle.

The plates appear to be secured by four bolts with the (nylock?) nuts on the inboard side of the plate (the exploded diagram in moss's parts book shows them the other way round)

Are they captive nuts?, as they don't want to budge and there is so little clearance between the nut and the axle case that it is difficult to get a spanner on them.

Dave
D MATTHEWS

how much grease do you have to put in the hub when you put new seal in. do you just fill the bearing up.
bob taylor

If you are stripping out the hub, be prepared to replace the half-shaft seals (paper gasket and o ring) as they will be disturbed.
If you jack up the car on the hub side (rather than in the centre under the diff) the oil will drain away from the hub so you shouldn't need to drain the diff. If you keep the axle level you will need to drain some oil out the diff.
Also, remove your brake shoes! You will probably get oil on them otherwise.
Graeme Williams

The hub bearing doesn't get greased. It is lubricated by the gear oil in the diff. When the half shaft turns, oil rides up it and on to the bearing. When you're installing it you can apply gear oil to the bearing to get it pre-lubed but that's all you need to do. Many people treat these the same as front wheel bearings but the design is different and has worked for many years on many cars without greasing them. Grease actually blocks proper lubrication of the bearings as per the original design. If you look at any manual for a car with a differential set up like this not one of them will tel you to grease the bearings.
Martin Washington

Dave, if l recall the nuts (or bolts if fitted from the other side) won't turn as one of the flats fits against a machined lip on the axle casing. They have to be undone from the drum side of the backplate
GuyW

What Guy said...but it does help if you can also get an open-ended spanner on the nut, as if they are tight/seized, it helps to stop the nut from trying to turn and getting chewed up.

I would also use a six-sided socket on the bolt head, if possible.
Dave O'Neill 2

Martin,

The Leyland workshop manual (AKD 4021),Section H4 Hubs - notes
'before refitting, repack the hub bearings with grease'

I agree that they are lubricated by the diff oil as on strip down its always only oil that is present, so can only assume it was/is to ensure lubrication until car angle/speed splashes it around.

R.
richard boobier

Guy//Dave,

Thanks for the advice.

Dave
D MATTHEWS

I fitted sealed for life bearings in the rear hubs. No problems.
That will start a run of comments but we used bearings like that in industry for years. And they took far more of a hammering that sprite hubs do.
Graeme Williams

I stand corrected, partially. I have a Bentley manual and an old Floyd Clymer manual and they both say to grease the bearings. But I'm used to American cars and unless they have special bearings, they don't require greasing of the bearings. I installed my Frogeye bearings without grease many years ago and haven't had any problems so who knows what is the "right way" to do it. I guess it all depends on the particular manufacturer.
Martin Washington

This thread was discussed between 31/03/2016 and 02/04/2016

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