Problem removing front wheel bearing retaining nut

[SteveHall64Healey]

I'm having difficulty removing the bearing retaining nut from the right-front hub. Normally these castelated nuts are only on with 5-7 ft.lbs., but this one seems immovable. I have removed the cotter pin cleanly and, through the hole in the hub, I was able to insert a rod completely through the nut - showing that there is no debris in the hole which might be holding the nut in place. Before I apply King Kong force to this, has anyone ever encountered this before or have any idea as to why the nut might be stuck on so firmly?
thanks,
steve
BJ8p1

 

[HealeyRick]

Factory recommended torque for the wheel bearing retaining nut is 40-70 ft/lbs If you're only wrenching 5-7, could be your problem.

 

[SteveHall64Healey]

Thanks Rick. I set the torque wrench to 80 ft.lbs. and the nut came off around 80 lbs. The driver's side hub came off around 5-7 lbs., and since My TR4a was also 5-7 lbs., I assumed they were similar.

My manual specifies a rather elaborate shimming process, and since I have no shims handy, I am wondering if this is really necessary. Can anyone comment on this?

thanks,
steve
BJ8p2

 

[bob hughes]

It has been said by a garage mechanic working on Healeys that similar bearing nuts on the Wolsley, Morris and Austins do not have shims etc. they rely on the lugged washer and tighten the nut to let the wheel rotate without play or catching then fit the split pin. However I have not tried it on the Healey and I know that the practice in the Healey work shop is to fit the shims. Surly when you removed the nut there were some shims behind the lugged washer?



Bob

 

[HealeyRick]

My manual specifies a rather elaborate shimming process, and since I have no shims handy, I am wondering if this is really necessary. Can anyone comment on this?

thanks,
steve
BJ8p2

John Twist explains why you need the shims for axle strength:

 

[SteveHall64Healey]

Thanks Rick, that's an excellent video. As I disassembled mine, I did find some shims, so I will see how it goes with them. If I understand correctly, the objective is to shim such that you have very little end-play, about 60 ft.lbs. on the castellated nut, good wheel spin, and the nut is aligned with the through-hole in the stub axle?
Steve

 

[Keoke]

Thanks Rick, that's an excellent video. As I disassembled mine, I did find some shims, so I will see how it goes with them.
If I understand correctly, the objective is to shim such that you have ZERO end-play, about 60 ft.lbs OR MORE. on the castellated nut, with FREE wheel spin, and the nut is aligned with the through-hole in the stub axle BY TORQUING THE NUT IN A POSITIVE DIREcTION IF REQUIRED
Steve

 

[John Turney]

I wonder if not doing that is why so many Healey stub axles have cracks?

 

[steveg]

Thanks Rick, that's an excellent video. As I disassembled mine, I did find some shims, so I will see how it goes with them. If I understand correctly, the objective is to shim such that you have very little end-play, about 60 ft.lbs. on the castellated nut, good wheel spin, and the nut is aligned with the through-hole in the stub axle?
Steve

Norm Nock (p57) recommends cleaning and lightly oiling the bearings, then setting up the shims with spacer but without oil seal. When you've got that right, grease the bearings.
Note there are two through-holes -- one vertical and the other horizontal. Since the threads are 16 tpi, one turn = .0625". That means with the relationship of the castellated nut to the 90degree holes you have 1/12 of a turn increments - .005" between hole/castle alignments. Moss tech can suggest how many of each thickness you need.

 

[Keoke]

i wonder if not doing that is why so many healey stub axles have cracks?

yes !!--Jhon
That spacer was added to stiffen the axel by forming a colum in compression. The shims are required to compensate for minor differences in the spacer's length due to minimal manufacturing tolerances and properly load the spacer.