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To install or not to install Front hub spacer

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The bearing spacer is needed to support the stub axle and strengthen it by drawing everything up tight. That way under heavy cornering demands any flex occurs within the tapered bearing and not on the stub axle. The shims are used so that there is no end float in the hub when set up dry and tightened down with the castle nut and washer. If anything the brgs. should be slightly loose and definately not tight which will spin the fixed inner race over time. Kevin
 
I've been wondering this question for some time too. No other vehicle I have seen has the spacer and many use smaller bearings for heavier vehicles without any problem.

One thing I guess it does prevent is movement of the outer bearing on the stub, a common problem with conventional-design bearings which are just effectively sitting there on the shaft. The bearing inner race tend to slowly rotate over the years which wears the lower half of the stub so they never feel tight, even though there is no play in the actual bearing race.

Are AH stub axles renown for failing? Should I be getting mine crack tested I wonder.
 
The spacer is very important. When you torque the spindle bearing as per the service manual with the spacer & shim pack in place [ 40 / 70 FtLB with 0.002 bearing clearance ] you are putting the spindle in tensile load. This allows the spindle to take a larger bending moment load because it's not starting at '0' load but at a negative load and the spacer is a larger diameter than the spindle as well.
To answer the question about any other car using this spacer design, the Chevrolet Corvette utilizes this spacer concept, I wonder why ?
I was at Mossport in Ontario two [2] years ago when a Lotus 11 broke a front spindle, the wheel etc. departed modifying the body along the way. The spindle was pure BMC design and when I looked - no spacer. Asked owner if he purposely didn't install them and he said they were not required - I beg to differ and the repair price will bear it out. Cheap insurance.
If you don't know the reason, and you can't find the designer, be careful.
Regards, Bob
 
They do fail even when you're on of the best drivers in the world.............
 
Thanks for the input. The spacers will be going back in and as soon as I get a chance I will be putting them back in my MGB also.
 
Not to beat a dead horse, but - absolutely, positively, be sure to install the spacer (distance piece) and shim it properly. One note bout the shims. My experience, in the past, was that new shims from Moss did not come in the thinner sizes that the factory fitted, which makes it difficult to get minimal end play in your bearings. That may have changed, but just be aware that the original shims came in sizes from .020, down to, as thin as .003,.004 and .005 thickness so you could get just the right end-play.
 
Read the thread Updated my Healey web site by Robert560. It has a video showing the front axle stub and bearing assembly from an MGB and goes into details of the mechanics of it all. I will be rechecking my bearings for proper torque now that it has been explained how to properly shim the spacer piece for proper fit.
Bob
 
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