TRExp

Spitfire & GT6 Forum

Drive shaft shims. A few questions

Moss Motors
AutoShrine Sponsor
AutoShrine Sponsor
AutoShrine Sponsor
AutoShrine Sponsor

JohnW63 John Williamson
Apple Valley, CA, USA   USA
We put in our CV style rear axles today, but it spawned a few questions regarding the shims at the end of the hub where it buts against the face of the axle.

1) I looked at a few places and found these shims are no longer available. I found one still on my old Rotoflex half axle, but it was pretty deformed. I found a bad in our boxes of parts labeled " Shims ? " that have various sized vert thin metal circles. Only 3 would be the right inner diameter for the shaft on the axle.

2) Do I NEED any with the CV style axle ?
3) How do you know how MANY you need ?
4) Rimmers has about 4 or 5 different thickness shims that they used to sell, but are all no longer available. How would you know how thick of a shim or combination of them to use ?
5) It looks like the shims go on the drive shaft before you slide the whole thing into the back bearing of the rear hub. Do I have that right ?
6) Do the shims need to be in very clean condition, or can I reuse what came off the old Rotoflex shims ?



Home of the 1969 GT6+ MK II resurrection project
and a sorry looking 1968 GT6+ parts car trying to stay whole.

. Hide banner ads & support this website by becoming a > Gold Supporting Member <
Bpt70gt Avatar
Bpt70gt Brian T
Westmoreland, NH, USA   USA
John, there are bearing shims and bearing spacers. No one I've found has these spacers. The shims are rare as hens teeth also. I did my CV conversion a couple years ago. There is a very detailed procedure to set the bearing end float. To tight and you'll burn the bearings up quickly, too loose and over a little longer time the bearing will likely fail. There are a number of good articles online showing the procedure. There were Churchill tools available in the old days but you don't need them. You will need a good dial indicator, some patience and you'll take it apart and put it back together at least 3 times. You also have to make sure the vertical link casting clears the new outer CV boot. Usually takes a bit of grinding to make the necessary clearance. If you looked at the Canley Classics website, they caution you to do this carefully or you'll have problems. They used to sell the CV kits but no longer. Rimmers has them but strangely don't sell the spacers. You need a variety of them to get the end float correct. You don't really need the thin shims if you take dial indicator readings carefully, you can use just the bearing spacer but that's why you need variety of them to select from. You will also need to bend the frame flange down to clear the inner boot. As I said, lots of good articles online. You only have a .002 to work with here. Do your reading first. Sounds a little daunting but it really isn't that bad a project. British Leyland put out a procedure as I show in the picture but they of course used the Churchill tools. I show some of the sizes in the photo. It's very unlikely that you could re-use your old shims and get the critical end float for the bearings. Precision is the critical word here. Do you have a workshop manual? You really should read that carefully.



Edited 1 time(s). Last edit at 2018-02-24 09:18 PM by Bpt70gt.


Attachments:
GT6 rear axle manual.JPG    31.1 KB
GT6 rear axle manual.JPG

shaft%20comp.jpg    8.4 KB
Sign In or Register to view this photo
RotoFlex Bearing Spacer Assortment.JPG    40.6 KB
Sign In or Register to view this photo
Bpt70gt Avatar
Bpt70gt Brian T
Westmoreland, NH, USA   USA
John, here is the quote from Canley Classics below. Your wheel bearings longevity will depend on doing this right.

Please note

Setting the wheel bearing end float on a rotoflex car (standard or CV conversion) is critical. If you haven't done one before and aren't armed with a factory workshop manual, a pile of shims, spacers, and a decent set of tools then we would suggest getting a professional involved. Please check with your preferred garage/workshop that they regularly carry out rotoflex rebuilds before entrusting this work with them.

. Hide banner ads & support this website by becoming a > Gold Supporting Member <
JohnW63 John Williamson
Apple Valley, CA, USA   USA
Yes, I have the shop manual. A quick scan of the index and checking the sections didn't tell much at all. What page does the detailed instructions start on ? Anyone have a good link to an online article, as you mentioned ?

" No one I've found has these spacers. The shims are rare as hens teeth also. "

So how can I possibly install these axles ? If I need to use them and be very precise, but these parts practically do not exist, then it sounds like we are well and truly S*** out of luck.



Home of the 1969 GT6+ MK II resurrection project
and a sorry looking 1968 GT6+ parts car trying to stay whole.



Edited 1 time(s). Last edit at 2018-02-24 09:50 PM by JohnW63.

Bpt70gt Avatar
Bpt70gt Brian T
Westmoreland, NH, USA   USA
John, in the thick (2" thick) red book---start on page 3-124 through 3-127. Study "Hub bearing end float". Page 3-126 shows the assortment of spacers. You don't need the shims, they are for fine tuning but if you measure very carefully and have the right spacer you can eliminate the shims. I never did like using shims on anything. Study page 3-124 Fig. 63.

If you have the dinky little Autopress blue book. Look at pages 77 thru 80 for similar instruction. 7:5 "Hub and axle drive shaft assembly".

You don't need the Churchill tools. Use a dial indicator, more accurate. Tolerance for bearing end float is .0005 to .0025. without grease , then you have to take it all apart again and pack it with grease and then put it all back together. The first side will take you a Saturday morning, the other side about half of that. Someday I'll write up a technical article when I have the time.

JohnW63 John Williamson
Apple Valley, CA, USA   USA
I found those pages on an online PDF. I will check the manual out, tomorrow.

Problem #1 ) We already greased the bearings and fitted the axles once. We stopped when we started discussing the spacers and shims and whether the parts boxes for this car had any. We found with paper thin shim on one old Rotoflex axle end.

Problem #2) I still have no idea where to get spacers, not matter how many afternoons I have to fit and measure the end float.



Home of the 1969 GT6+ MK II resurrection project
and a sorry looking 1968 GT6+ parts car trying to stay whole.

JohnW63 John Williamson
Apple Valley, CA, USA   USA
Are shims needed on the front hub too, as this TR6 web page ? We installed our fronts like we would with old American cars. Tighten down enough to move smoothly , then find the nearest hole with castle nut and put in a pin.



Home of the 1969 GT6+ MK II resurrection project
and a sorry looking 1968 GT6+ parts car trying to stay whole.

. Hide banner ads & support this website by becoming a > Gold Supporting Member <
Bpt70gt Avatar
Bpt70gt Brian T
Westmoreland, NH, USA   USA
No, you are fine on the front. That's old school and you're OK up front exactly as you have done.

jimgt6 Jim E
Seekonk, MA, USA   USA
This might help. There is a radius on the CV joint that will not allow the stock shims to properly seat.



Edited 1 time(s). Last edit at 2018-02-24 11:00 PM by jimgt6.

. Hide banner ads & support this website by becoming a > Gold Supporting Member <

Attachments:
GT6 Hub Bearings with 1 Spacer.pdf    138.4 KB

JohnW63 John Williamson
Apple Valley, CA, USA   USA
Thanks, Jim.

I wish there was a diagram with the specs, for clarity. I'll see if I can find at least a picture of one for reference.



Home of the 1969 GT6+ MK II resurrection project
and a sorry looking 1968 GT6+ parts car trying to stay whole.

Bpt70gt Avatar
Bpt70gt Brian T
Westmoreland, NH, USA   USA
Jim is very correct, during the manufacturing process of the CV axles, they left a small radius so if the spacer isn't chamfered, it won't seat and you won't get an accurate reading. I put that chamfer on my spacers. Just have to make sure the chamfer faces the radius. The stock axles are different and didn't need that chamfer.

Hopefully more GT owners in your part of the country John, and will chime in here and give you a hand.

John, in the morning I'll take a close up of the spacer so you can clearly see what we are talking about.


Bed time.

JohnW63 John Williamson
Apple Valley, CA, USA   USA
Is this one of the shims ?

http://www.angclassiccarparts.co.uk/home/triumph-5981/gt6/suspension/rear-hub-bearing-shim-0.003-gt6-mkii-iii-to-kekf20000



Home of the 1969 GT6+ MK II resurrection project
and a sorry looking 1968 GT6+ parts car trying to stay whole.

jimgt6 Jim E
Seekonk, MA, USA   USA
Yes, They were used up to two in conjunction with spacers

The factory only had 5 spacers

Pt# 152483 .139"
Pt# 152484 .141"
Pt# 152485 .143"
Pt# 152486 .148"
Pt# 152487 .155"

This gave thicknesses from .139" to .161"

Shim was Pt# 142340

Note: 142340 was superseded by 140793.

The roadster factory lists this number as current also for $2.48



Edited 1 time(s). Last edit at 2018-02-24 11:27 PM by jimgt6.

JohnW63 John Williamson
Apple Valley, CA, USA   USA
I want to verify something that I believe I have correct in my head, but exploded diagrams don't help.

The spacer and shims go between the nose end of the hub that slide into the rear upright and the machined end of the CV axle and can not be slid in before the hub goes on the shaft AFTER the bearings have been installed, right ?

Is it easier to remove the upright and pull it off the drive shaft or leave it in place and remove the driveshafts ?

We have them all in place but have not put the washer and nut on the end of the drive shafts and tightened them down.



Home of the 1969 GT6+ MK II resurrection project
and a sorry looking 1968 GT6+ parts car trying to stay whole.

jimgt6 Jim E
Seekonk, MA, USA   USA
The outer bearing seats against its shoulder, but the inner bearing is not driven home. tightening the CV joint and correct spacers is what sets the end play. You must sneak up on it by using a larger than needed spacer and measuring the end-play to get it correct with the final set of spacers. the outer oil seal is placed on the hub and can be forced into place on the vertical link after the hub is tightened

I remove the vertical link and lock it in a bench vice.



Edited 1 time(s). Last edit at 2018-02-24 11:39 PM by jimgt6.

. Hide banner ads & support this website by becoming a > Gold Supporting Member <

To add your reply, or post your own questions




Registration is FREE and takes less than a minute!


Having trouble posting or changing forum settings?
Read the Forum Help (FAQ) or contact the webmaster