half shaft flange oil leak

[steve c]

hi, ive changed the gasket twice now on my half shaft flange, but cannot stop the oil leak, ( when i first took it off there was no gasket at all) i am now going to strip out the complete hub and renew every thing, to try and stop this leak, how much oil should be behind the flange? as just one small bolt holding it in position seems a bit flimsy to say the least, lastly are the rear hub nuts handed, ie left rear comes off to the right? thanks steve

[bmcecosse]

Yes - the left hand nut is left handed. The wheel studs hold everything together - the single screw is just there to align everything as you assemble it. You need to decide if the leak is from the half-shaft/hub joint - or from the oil seal at the back of the hub.

[oddbod]

Its important to change the Paper Gasket as well,but you MUST clean all the old paper gasket off both mating faces.Did you change the rubber O ring gasket too? I know some older Moggies dont use this gasket though.

[steve c]

the leak is definatly from the halfshaft/hub joint, as i said when it first started leaking there was no gasket on it at all,as for the one screw just to align it and the wheel studs holding it all in place, i understand what you are saying, but that was when mine first started leaking, with the wheels off to adjust the brakes

[bmcecosse]

When the O ring is used -I can't see the point of the paper gasket......

[steve c]

what and where does this paper gasket go ?? as i said mine had nothing at all to start with, and all i fitted was the standard card type gasket between the flanges.

[bmcecosse]

That's it - paper/card - although all I have seen were definitely more paper than 'card' !

[kennatt]

I tried everything to stop this on my 55,as soon as I took a wheel off it leaked ,new gaskets (Has no O ring grove which I belive was a later mod)Gasket cement,even took the half shafts out and cleaned the faces up with wet and dry.I have found that the only thing to do is make sure that the side you are working on is jacked up high enough to let the oil drain away from that side,before removing the wheel.Was talking to chris at tom roys about this and he says that that is why the early models have a groove at the botom of the back plate so that any oil that does get in runs down and out and dosent get onto the shoes. often wondered why that particular shape was put into the backplate just shows that they anticipated the leakage.

[oddbod]

I could only fill my Diff via the half shaft route,and made sure one side was Oil seal/O ring and paper gasket tight,put the wheel back on without the Brake pads,dropped that side,lifted and stripped the opposite side filled the diff with the recommended 0.85l of EP.90 via the now raised axle stub,had my tea then chcked there was no oil visible behind the back plate on the side already assembled,put everything back together,put the second wheel on,again without the brake shoes,dropped the car onto its wheels,had a brew,then checked both sides for evidence of oil,put the brake shoes back on,trimmed up the back brakes and went for a spin. I kind of figured out that if the axle was level and I removed the half shafts then oil would spill cos the oil goes to the end of the half shaft,or you wouldn't need an oil seal seal. But if one side was higher than the other,and the seal on the lowest side was sound,then the oil should stay in the axle and Diff.

[steve c]

new rubber sealing ring and paper gasket, no leak for two days, but now started leaking again, realy have had enough now, MOT in two days, never rains but it pours.

[steve c]

last desperate attempt to seal the half shaft flange to morrow, ready for MOT on tuesday, any body got any ideas or secret tips on how to do it, ?? both of my surfaces are clean, straight, and clean, i have been using a new gasket and rubber seal, should you use either the paper gasket or the rubber seal but not both together?? any help on this would be greatly appreciated, getting desperate now, ( had to cancel the MOT last week because of the brake light switch) regards steve.

[MarkyB]

You said

when it first started leaking there was no gasket on it at all

And

mine first started leaking, with the wheels off to adjust the brakes

It sounds like the wheel nuts were holding it together OK before you disturbed it, they do at least have the benefit of putting pressure on equally unlike the locating screw, which shouldn't be done up very tight.

I'd examine the mating faces for any issues, over tightening can sometimes raise a ridge around threads.
Maybe put a clean sheet of paper between the surfaces to work out where they meet and where there may be a problem?

[bmcecosse]

Perhaps the final drive is over filled ? And/or the breather on the casing is choked ? Is the rear hub perhaps moving in/out even with the 'big nut' done up tight?

[Declan_Burns]

I have always used sealant as well as the paper gasket and the O-ring and never had a leak. Did you replace the lip seal at the back of the hub?
Regards
Declan

[kennatt]

stick a load of gasket cement round the flanges and bolt the wheels on while its still wet,that cured mine from leaking but as soon as you remove a wheel its liable to leak again,so may need to redo,(Mine did)

[Chris Edgar]

As previously mentioned...make SURE that the breather is not blocked with gunge.
& the diff not overfilled.

[mowogg]

I had the same reoccurring fault for 10 years. I tried most things -gasket, sealant, no sealant both seals, bearings but it kept returning.

Eventually I have solved it by stripping everything down and cleaning it. to do this you need or remove the hub, and back plate to effectively clean the area –the rear seal will not work if this area is damaged. I understand corrosion in this area can be an issue, but it was fine on mine. I replaced both bearings for new in the process, although these did not have any detectable wear

I suspect the two key issues I had was

1.blockage of the breathers on the back of the hub -these are a very small hole on the underside of the car
2. Cleaning the hub assembly around where the back plate is.

I have heard a theory that lateral play in the bearings, can result in repetitive sideways movements. without effective breathers, the oil can be pumped to the bearing end and eventually leak?

Hope this helps