How tight to do up the wheel bearing nut?

I take it this is a front bearing?

If so, I always used to tighten these up very slightly with a bar (and I mean very slightly), back them off and then tighten by hand. It can help to do this with the wheel on and give it a wiggle as you tighten the nut, keep tightening until you can't feel any play on the wheel - this is literally to the point that the play stops, if anything leave some play rather than overtighten.

The message from snipped-for-privacy@myself.com contains these words:

My Haynes says 40-70 ftlb - which is a huge range. Between "Not terribly firm at all" and "Mdium tight". It also gives a long and complicated procedure for getting the right shims in the front bearings.

You could go buy a torque wrench - Argos do 'em for a tenner or so.

There shouldn't be any play in the suspension. A small amount of play in a taper wheel bearing is OK, though. But has an MGB taper bearings? Things like the earlier Austins that used the same type of suspension weren't.

However, if it is an adjustable type, tighten it moderately with a spanner to seat the bearings. Then slacken. Then tighten with your fingers as tight as you can and back off to the first hole. You won't be far out. Something like 5mm movement at the top of the tyre is OK.

Assuming they are Timken taper bearings, the nuts should not be tight at all. In effect the nut is only used to adjust, and set the play in the bearings. The aim is to have as little play as possible, so even after they're set, the nut is not actually loading the bearing at all. Up to 0.75mm play at the wheel rim is permissable. Which might be the difference between a setting that's too tight and a looser setting where the split pin can still be fitted. Initially they are lightly tightened to ensure everything is seating properly. Then backed off and adjusted as above. Mike.

Sorry to correct you Dave. but 5mm is definitely too much. Maybe you meant 0.5mm. :-) Mike.

Thanks for the pointers. I have found out why I could not tighten in up enough to stop the play, it is because the play is in the ball joints. Oh bother. I guess I shall have to take them apart tommorrow. Probably I will just have to change the shills?

Hi Again,

I replyed before I saw all these messages. Bloody google.

So, there is play at the top and bottom of the bit of metal marked 21 in the diagram at [1]. This is wrong I belive? This piece is known as the swivel axle?

I guess I need to carry out the procedure as described in the haynes manual as "Swivel axle and swivel pin (kingpin) assembly - removal, dismantling, reassembling and refitting". Bother again. That involves removing the coil spring, could be a bit of a job. What do you reakon about the chance of 2 relatively inxperienced but vaguely practical blokes doing it this weekend?

My mate reakons I will only need change the shims. What do you lot reakon?

Thanks all.

You should buy a set of axels and pins and replace the units - the bushes which are pressed into the swivel are reamed to suit the pin.

Both the pin and the bushes will be worn as well as the lower horizontal bush.

Assembly will have to be setup and shimmed then put into place.

Buy all the parts in the front suspension you should replace them all.

Some of the advice that has been given is misleading.

The factory setup on a MGB has a spacer between the bearings, and end float is adjusted by adding or removing shims. NOT by tightening and slacking the nut.

The correct end float is 0.002" to 0.004" This is obtained by adding a surplus of shims, tightening up to 40 lb.ft, measuring end float with a dial guage, and then reducing the shim thickness by removing shims to give the correct end float. You must ensure that there is sufficient shimming in place for the initial tightening and end float measurement. Having less that required may damage the surfaces of the bearings.

The correct torque is 40 to 70 lb.ft. This is obtained by tightening to

The whole process is best carried out with all components dry and clean, and the oil seal removed. Once the correct end float is obtained, dismantle again, grease the bearings, replace the seal and reasemble.

Ian F

That's what I would have expected given it's based on the '40s Austin A40 (Devon) front suspension, and all these had non adjustable bearings in the conventional sense.

I was assuming they were taper roller bearings. From what you say, it would appear that they are 'side and thrust ball bearings' which are more critical in their setup. Mike.

They are taper roller bearings, but they do have spacers and shims. I assume that whoever designed the setup had reasons.

While the system on a MGB would appear to be different from a 'normal' setup for taper rollers on other breeds, the use of a spacer was consistent with MG practice on the MG Y type, followed by the TD, TF, MGA, and also used on the AH Sprite/MG Midget, although all these cars used ball bearings. It may have also been consistent with Morris and Austin practice on other cars as well.

It may well be that the use of a spacer on the MGB was a carry-over from earlier practice, but the use of a spacer in compression adds greatly to the stiffness of the stub axle, ensures location and alignment of bearing inner races, and prevents rotation of the inner races.

I agree that it is easier to setup a MGB bearing without shims and spacers, but from a design point of view it should be kept in mind that this may not meet the requirements that the designer intended.

Ian F

Thanks for all the pointers. I decided I was not quite up for a complete suspension rebuild today, and I gave it a good greaseing and that stopped the movement. I guess that will do for the minute. I shall have to fix it properly when I have a bit more time.

Anyone any idea how long I could expect to drive it in this condition?

David

have a look at

Categories there for most groups of MG's. (General and Technical groups for MGB)

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Cheers Ian F

'normal' setup

Perfectly true - I used this procedure on my Midget. An article in the MGOC magazine detailed it once, and I still have it.

Russell