Rear hub

[Roger K]

Just changing my Bastuck rear hubs back to a pair of reconditioned originals.  My question is, can I simply remove (ha ha, 'simply') the hubs, and slide the replacements on and tighten as before?  Or will removing the 'old' ones disturb seals, bearing position etc. on the axle shaft?  In other words, do I have to strip the whole thing and setup again, or can I just* swap the hubs over on the tapers?

 

* there I go again, 'just'.... I got them off, genuine 70's Churchill tool and a bit of heat and bashing later.

[RogerH]

Hi Roger,

what car are they fitted to.

 

Roger

[Roger K]

Non-roto late GT6 Mk3, sorry. 

[RogerH]

Thanks Roger.

Just asking in case it was a TR rear hub.  Rebuilt ones are getting dangerous.

 

Roger

[Pete Lewis]

me i would just refit the hub and torque the nut with wheel wheel on the deck 

recheck after a good few miles 

yes the hub pulls the shaft thro the bearing but you have no idea the taper tolerance  so cant determine its final resting position 

Pete

[Roger K]

Thanks Pete, of course it’s also a different hub now so it may not be tight against the bearing. Not sure if that will matter or not, but I’ve taken the axles out so many times in the last couple of weeks I can’t face it yet again. 

[Roger K]

Typical, might have guessed I wouldn't get away with it. 

Fitted the original hub back on, and there's a 3/4" gap between the brake drum and the backplate.  The trunnion and bearing have moved on the axle shaft, don't know how as the puller doesn't touch it.  So it was out with the puller yet again to remove the axle and am working on the bench now.  Had to remove everything to start again with the flinger, as pushing it all further in has opened it up a bit and it's loose.  Needs tapping back into shape or fitting another, then start again.

I still can't quite get my head around the fact that the bearing and trunnion are pushed into place by the hub on the taper, and only retained in position by friction against the axle shaft running through it.  Basically, I guess that means that it's the combination of the radius arm and the shock absorber location that hold the vertical link in the correct position.  Why couldn't Triumph have fitted a nice, simple little live axle at the back?  The front suspension, steering, drivetrain (diff excepted) are almost masterpieces in such a small package.  Pity the back end is so poor as it really lets down what is otherwise a brilliant design.  Really bored with this now, and still don't have great confidence in any of the wheelstuds that started all this.  Rimmers still haven't told me who makes their replacements.  I'll be glad when the XK is back from the paintshop and I can push this to the back of the workshop!

[johny]

Once set up the design does work though, honest*

 

*Turning the car over through axle tuck under not included in garantee...

[Roger K]

Don't worry, I'll push it very slowly, with wide-radius turns only.

My paranoia has even made me drape a heavy cloth over the LH front wheel now that its wheel nuts are done up (only to 30ftlbs), as I don't want one flying off and denting the Cooper S* parked next to it...

 

*That's a thought - the Cooper S also has 3/8" wheel studs, and the figure for those is 40-45ftlbs.  Something badly wrong with these studs, as if I didn't already know that.

[Pete Lewis]

I find it amazing the forces of things like roundabouts and the like are all contained by the bearing grip on the shaft ...its nuts    but only lasted 50years  

and the fact it cant go far as the diffs in the way 

not strictly true but its a odd way by design 

Pete

[Gully]

40 minutes ago, Roger K said:

 Why couldn't Triumph have fitted a nice, simple little live axle at the back?  

Because the PR team was focused on Triumph's marketing claim that all their cars had independent suspension... There's a story in one of the Triumph history books of a live axle Spitfire being built to address the tuck under - it needed some small chassis changes and raided the TR4 parts bin, but was quickly crushed as it handled fantastically well, but was 'off message' in PR terms...

Gully

[NonMember]

1 hour ago, Pete Lewis said:

I find it amazing the forces of things like roundabouts and the like are all contained by the bearing grip on the shaft

But they're not! Really not. The bearing only supports weight; all the lateral forces are transmitted along the shaft to the diff. The thing that should amaze you is that the UJ survives this!

[PeteH]

1 hour ago, NonMember said:

But they're not! Really not. The bearing only supports weight; all the lateral forces are transmitted along the shaft to the diff. The thing that should amaze you is that the UJ survives this!

Via 4 x 7/16 Bolts?.

Pete

[Roger K]

2 hours ago, NonMember said:

But they're not! Really not. The bearing only supports weight; all the lateral forces are transmitted along the shaft to the diff. The thing that should amaze you is that the UJ survives this!

On my old Vitesse, in 1976, it didn't.....

I had all the traditional Triumph things go on that, at just 9 years old.  Absolutely rotten door bottoms, chassis outriggers non-existent, front trunnion failure with car immovable at a junction for 24hrs, rear axle UJ snapped in half.....  can't really complain, I only paid £5 for the car and another £25 for the Sharp radio cassette.

[Pete Lewis]

2 hours ago, NonMember said:

But they're not! Really not.

yes i did say.............. the diff gets in the way   

Pete