MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGA - Rear Wheel Bearing

Following my locked wheel problem, I have eliminated brakes and diff.

Having removed the half shaft and started the replacement I discovered that the bearing in the hub gets quite notchy as I tighten the nuts holding the (wire wheel) half shaft onto the hub face. Back them off and it's ok.

It wasn't doing it before I stripped the shaft out because that was one of the things I checked.

I have measured the gasket and it is 0.01" which I believe is the recommended thickness and I am using an O ring which seats neatly in it's groove (and hasn't fallen out).

There appears to be a gap of a mm or so between the two mating surfaces in the area of the studs and this nips up as I tighten the nuts. The axle nut is tight.

Bearing failing or something else? The notchy feel is weel on the way to suggesting it could lock.
Graeme Williams

Is the bearing fully seated in the hub?
I would have thought that undue side loads would cause a tight but smooth feel, so if its notchy, the brg may be shot.
Art
Art Pearse

I had exactly your symptom when I had the splined hub replaced. The shaft was hitting the diff at the far end so I had about a sixteenth gap between the two mating surfaces. Tighten the nuts and the shaft locks up. If you put a broom handle into the hole it will bang up against the diff so you can get a fairly good measurement of what the length of the shaft should be to measure against your shaft. I had the splined hub pushed on by another sixteenth and all was well. If you haven't replaced the splined hub I cant think what else could have changed to prevent the two surfaces coming together.
AR Terry

Been on holiday for 10 days, so just picking up the thread. Not ignoring the kind replies!

Art: I wonder whether the the inner race is held off the step by a gnat's so tightening the h/shaft to the hub is forcing the outer out of line with the inner. But I agree it may well be shot but I thought I would look at the "doesn't cost £45 for a part" options first.

AR: I will check that just in case. The hub hasn't been replaced but you never know!
Graeme Williams

Pulled the bearing and it doesn't feel good so I have just bought a replacement. Something is "catching" sometimes when I rotate it, suggesting there may be a foreign body inside but it won't wash out. Alternatively I wonder whether the side of the ball track has been damaged which could explain the fact that when I tighten the half shaft it becomes more noticeable as the outer race becomes slightly pushed across compared to the inner.
Graeme Williams


In note above you say the gasket is 0.01 in thickness, maybe just finger trouble but here is the comments from Barney G on the subject.

'MGA rear axle bearing hub gasket must be 0.010 inch thick paper for proper clamping fit of outer bearing race. Paper too thin could lead to deformation of the rotating bearing housing and/or the halfshaft flange or splined hub flange. Paper too thick could leave the outer bearing race lose to walk around (orbit) in the rotating hub, ultimately causing hub housing wear and oil leak.

Hope this may help.
Regards
Alan
AR Terry

Alan: had checked with Barney's site, and I measured three gaskets together to get 0.03" or 0.01" per gasket (10 thou in)
Graeme Williams

This thread was discussed between 12/06/2016 and 28/06/2016

MG MGA index

This thread is from the archive. The Live MG MGA BBS is active now.