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MG Midget and Sprite Technical - Play in rear hub/half shaft

Right, this morning: new oil seal into hub, new bearing into hub, hub on, tab washer on, hub nut on and tightened up with three heaves on 2 ft bar.

O ring and gasket on, half shaft in. Holding the half shaft and hub together tightly there seems to be a bit of fore/aft play in the hub/half shaft assembly.

Is this cause for concern, or will the play get taken up when everything is bolted up tight with the brake drum/wheel etc. on?

Looking at it all now, the whole lot just gets held together by a couple of weedy countersunk screws whilst the wheel isn't on, right?!

Thanks all,
Malcolm
M Le Chevalier

Just some more thinking whilst I wait for the collective genius of the BBS to post. I am wondering if the gasket is too thick...? They seem quite chunky, I am sure I read somewhere they are supposed to be very thin. I can't remember exactly what came off the car.

Either that or if the hub is worn (it looked OK). Will get down to the garage again tomorrow and crank it all up tight and check again.

Malcolm
M Le Chevalier

You are correct.

Put a wheel on there and see how it feels.

The gasket should be no more than .010"
Dave O'Neill2

The BMC workshop manual says that the bearing should protrude from the bore in the hub by 0.001"/0.004" (0.025mm/0.1mm) to make sure that the bearing is clamped properly when the halfshaft is in place.

Yes, the real clamping is done by the wheel nuts.
Richard Wale

So when you take the wheel off, what theoretical stops all the oil weeing out as the clamping force on the gasket and seal are released?

Anybody ditch the gasket and just rely on the o ring?

Cheers,
Malcolm
M Le Chevalier

They do sometimes weep a lttle, although the gasket tends to stick to both surfaces.

Don't do away with the gasket, it is a vital component, as it also serves as a shim.
Dave O'Neill2

There should be a countersunk screw through the flange on the halfshaft (or hub extension for wires)which holds it all together when the wheel is undone.
G Williams

Its possible that the bearing outer race may have been spinning in the hub and has worn the recess so the fit is loose, even when the flange is tightened firmly. If there is indication of wear then I would try using some bearing seal which should take up any slack. If it hasn't already worn the hub too much, then it should clamp up tight when you add the wheel nuts.
Guy W

My way of ensuring a weep free hub is as follows:
Always use a new O ring AND gasket. Clean the hub face and half shaft very carefully. Its useful just to run fine 8oo grit paper on the half shalt face. but clean it well afterwards. I personally use blue hylomar on the joint faces but its optional. Put the half shaft in and tighten the hub and shaft in with the counter sunk screw. I then put a couple of large spacers or old nuts on the wheel studs and then nip up a couple of wheel nuts to make sure the hub is pulled up tight, I then retighten the small countersunk screw. It often goes another 1/4 or even 1/2 turn. Take off the wheel nuts and spacers and refit the drum. Make sure the drum is fitted so you can get to the head of the existing countersunk screw already in the hub. There is a hole in the drum for this.Tighten the two countersunk screws holding the drum on and re tighten the screw in the hub through the hole in the drum.
Bob Beaumont

Hi Bob,

The more I thought about it all last night the more convinced I became that doing exactly what you described was what I needed to do. You have kindly confirmed said thoughts for me.

I will crank things up snug with the wheel nuts tonight and check again. I suspect I was just tired and prematurely panicking!

Cheers all,
Malcolm
M Le Chevalier

Played around tonight.

1. Put spacer washers and nuts on the wheel studs and nipped them up. Still loads of play.

2. Removed gasket (but not o-ring) and tried again. Seems OK.

I compared the gaskets to some 0.8 mm gasket paper I have. They look about the same thickness. Definitely >> 0.01" (0.25 mm) Dave recommends.

Conclusion: the gaskets are crud. Sound reasonable?

Cheers,
Malcolm

M Le Chevalier

Malcolm.
I had the same trouble when I replaced a leaking O ring and gasket the new gasket was so much thicker than the old I ended up with play the same as you. Made a gasket from thin paper and used Hylomar and lost all the play. Been OK for the last 3000 miles

Mike
Mike J Pearson

Interesting. I have not experienced this problem. The gaskets I used came from a well known supplier and were certainly not thin paper. I assume the bearing has bottomed out properly in the hub?
Bob Beaumont

I can affirm that original gaskets were thicker than the modern repro ones, however I suspect the material was designed to crush more, filling uneveness and imperfections thus giving a better seal. I have small stocks of both and the BL ones are more like very thin card or composition, not just stamped from a sheet of paper.
David Smith

I forget, does the inner edge of the paper gasket overlap onto the outer race of the bearing? If it doesn't, then I would have expected a thicker gasket to reduce the clamping / nipping up of the bearing, rather than the other way round.
Guy W

Don't think it does Guy.

I have ordered new gaskets to see if they are any different. Might get some 0.15 mm gasket paper too but perhaps that is treating the symptom not the illness and actually I need to look into some new hubs :-(

Will try to get the other side together sometime this week and see if I have the same problem.

Malcolm
M Le Chevalier

Just another thought.

Would it matter if I had swapped the hubs side to side?

I made sure to mark the half shafts left/right but not the hubs and they may have been swapped.

Would matching them back up help? Not entirely sure why, but just a thought.

Malc.
M Le Chevalier

No, swapping hubs side to side should make no difference.
Dave O'Neill2

The hubs make no difference. On my frogeye the left axle shaft has a green dot in the middle of the shaft the right one has none
Flip
Flip Brühl

This thread was discussed between 16/02/2014 and 19/02/2014

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