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MG MGA - Front hubs and bearing fit

I know this is and old Chesnut but I am new to MGA.
so i need a lot of help.
Bought all new hubs and bearing from the USA and supposedly they are British made and of good quality, but ... new outer bearing just slips right out of the hub too easily following installation. Certainly not a really good interference fit.I have fitted the large bearing and the old brake drum studs, so not an easy return to sender for a replacement situation.Failing the use of Loctite ,what should I do?
R.L. Olsen

You need to determine if the nearing OD is too small or the hub bore too large. I doubt the bearing is the problem. Who was the supplier? At least contact them and explain the problem and see what they offer to do.
Art Pearse

RL, when I fitted new front hubs I also found that the outer bearings almost slipped in and were not an interference fit like the originals. Funnily I could hardly pick up the difference in diameter between the new and the original bearings with a micrometer. I went down the loctite road but couldn't get it placed properly and was left with hard lumps of loctite that potentially would get into the races. I tried various other makes of ball race with no difference. At the time I talked with Barney about this and it was good to stop me fretting. My hubs have a small but constant play when rocked in the vertical plane. It doesn't get any worse and I've stopped worrying about it because I'm not sure there's anything you can do. Interestingly I think the manual warns about too much refitting of this outer bearing, perhaps because it can suffer v.small deformation. The real problem is that the MGA does not have tapered bearings. Read Barney's site and see if your play is within the limits he quotes. I'm assuming here that your bearing is not grossly slack. I think that is difficult not to have some play with a traditional ball race since the race has to have some small amount of tolerance.
J H Cole

there is a difference between running clearance between the balls and races, and the fit of the bearing in the housing and on the shaft. The latter should be slight interference for sure.
I found that you need to order these bearings with tighter than normal clearances. Standard is a C3 which will give a definite looseness at the rim. Order a C2 or C1, or ask you supplier.
If the bearing falls out of the hub on its own, you do need to fix it! One possibility is get a shop to knurl the inside bore, which causes raised ridges and will tighten the fit. Not ideal but a choice.
Art Pearse

Thanks Art and JH,
New Hub with Moss P/N sent to Australia from US.
Not worried about sideways movement or slight wobble,but I am concerned that the small outer bearing could spin in the hub because it is not a tight interference fit.My supplier is looking for a solution, maybe a new hub is coming my way...maybe!!!.Still would have to punch out the large inner brg and the brake drum studs to refit.
this I do not want to do.
Perhaps a beautiful 59 MGA is worth the pain.
thanks ...Richard
R.L. Olsen

http://www.ntn.ca/fits.htm

Try this site!
Art
Art Pearse

The TIMKEN part # for the MGA 1500 front wheel bearings are 304WB (NAPA part # 6304J)for the smaller, and 306TB (NAPA part # 6306J) for the larger.

The NAPA parts manager said that the larger bearing is a fairly common bearing used in manual transmissions. The quality, finish and feel of the Timken bearings is definitely superior to what I received from my supplier, (who otherwise has shipped very good quality parts.

Some of the bearings now are made with a metric being the priority. Mike the bearings and see if the smaller diameter is closer to an even metric number than SAE.

Part Number 304WB
Bore 0.787
OD 2.047
Width 0.591

306tb
Bore=1.1811", Outer Diameter=2.8346", Width=0.748"

Russ
Russ Carnes

The original post timed out. Update:
The TIMKEN part # for the MGA 1500 front wheel bearings are 304WB (NAPA part # 6304J)for the smaller, and 306TB (NAPA part # 6306J) for the larger.

The NAPA parts manager said that the larger bearing is a fairly common bearing used in manual transmissions. * The quality, finish and feel of the Timken bearings is definitely superior to what I received from my supplier.

Some of the bearings now being made in the Orient with a metric being the priority. Mike the bearings and see if the smaller diameter is closer to an even metric number than SAE.

Part Number 304WB
Bore 0.787
OD 2.047
Width 0.591

306TB
Bore=1.1811",
Outer Diameter=2.8346",
Width=0.748"

* For example:

http://www.rockauto.com/catalog/x,carcode,1316833,parttype,8300

1998 : NISSAN : PATHFINDER : 3.3L V6 : Transfer Case : Input Shaft Bearing Price $22.79 Add to Cart
TIMKEN Part # 306TB More Info 0.748 in. Width; 0.748 in. Width



Russ
Russ Carnes

I had a similar problem with a (Nuffield) Riley many years ago. I suspect that the bearing carriers were a malleable material and thus never go back as tightly as they do the first time! I had the interior faces of the hubs knurled which overcame the problem.
Barry Bahnisch

Russ, all the bearings are made to whole mm dimensions primarily.
Art Pearse

This thread was discussed between 18/11/2011 and 26/11/2011

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