today I made it to our MOT. Everything working, brakes perfect, but I met with a very careful examiner.
He found the right sill in the rear part rusty, the left rear wheel hub had excessive play and the left inner tie rod end worn.
The thing that shocked me most was that I couldn’t find any replacement part for the Adwest inner tie rod end (C.45303). Did I miss out on anything? Superseding part? Repair option? I wouldn’t like to swap out the entire rack.
If I understand correctly, to adjust the wheel hub end float I need to get the adjusting shims. The ROM cites spacers, and I take it they refer to C.38324. Is there any way to anticipate which one to buy? - They are way to expensive to buy them all!
As Robin said, you should establish if it’s the hub bearings, the half shaft U-joints or the output diff bearings.
Any leaks at the diff?
As for the hub shims, you could fabricate them from a brass sheet of the appropriate thickness.
Relatively easy to do.
I chose to set them with a slight preload by the way.
The ‘from scratch’ procedure involves hub carrier removal, Jochen and, using a calibrated collar, measuring endfloat. The calculate the shim size required to get the specific play, 0.002" to 0,006" - and install the proper shim.
On car; you may get away with push/pull on the hub - measuring the actual play with a micrometer. Best done with the drive shaft disconnected. However, you now need to remove and measure the shim fitted - which may have a letter stamped to identify its thickness. Then add the measured endfloat to the fitted shim’s thickness - then subtract the spec endfloat; this gives you the thickness of the desired shim…
You can then order the shim required - or fabricate your - own as Aristides outline. There is no way of anticipating the required shim thickness - you must measure the existing shim as a reference…
Of course, as others have stressed; verify that other factors than shim adjustment is what is required…
IIRC , if you have excessive play, you use thinner spacers so you can thin them on a file or sheet of glass with wet and dry paper. I found it easier to remove the entire halfshaft and do the measurements on the workbench. Helps if you have a micrometer so you can ensure you grind the spacer evenly around its circumference otherwise you might get an erroneous measurement. It’s a bit slow going, but better than waiting for a selection of spacers.
How much play is it? Try another TÜV and leave it, unless it is actually excessive. Some expect things that these cars weren’t capable of from the factory. I‘ve driven a car where you could rock the rear wheels a lot, and it definitely improved handling when fixed. But that was a lot, and it never felt dangerous.
If you can’t find one try an used one, but it has to be very good as this is sort of critical. There might be two versions, one with a nylon spacer and one with steel? Look in england, these must be available.
As for the rear hub play: I’ll certainly double check. Actually, I didn’t touch the wheel, but I could see while the guy rocked it, that it had clearly more play than the other wheels … even though my Spitfire has even more:-/
Unfortunately, if the play has increased I’m afraid I will need a thicker spacer, Kevin. So fabrication “in the shop” appears the only alternative unless I want to block a space in the shop for +3 days:-(
Thinking about Aristides’ suggestion I was wondering whether I just should order the biggest spacer and be ready to mill it down to the correct measure. While I have never touched a lathe myself I know someone who could do that …
Frank, do you have experience with measuring end float just with a micrometer? The ROM specifies a particular instrument which I don’t have access to. Do you remember how you got a simple micrometer to indicate the correct measure? - After all, we’re talking 0.005" …
As for the inner tie rod ends: I got misled by the headline on p. 1I 10R of the parts catalogue last night. In fact, my car is earlier and I need pt. # C.33423. All I found so far is JLM409 which is claimed suitable for SII cars. Although they are made for the Adwest type steering rack they have metric threads. I guess this is wrong, correct?
Besides the inner tie rod end there is also a certain problem about the tightness of the rack. So my intuition would aim at tackling the steering rack seriously, trying to get it tight(er) and replacing the inner tie rod end while keeping the ball lower on the rear hub … Then again, if I can’t source a suitable tie rod it doesn’t make much sense to reseal the rack … Questions abounding …
Thanks again for all of your help - always happy to read your advice and experience!
The only way to accurately finesse a spacer is on a surface grinder, these will get down to an accuracy of +/- .0001”
However I still think you need to check the other bearings before tearing into the hub.
I remember reading in someone’s post in the past, that the rear hub can develop some slop as you describe if/when the bearings are a tad worn and replacing the (Timken brand) bearings will bring things back into spec without messing with changing shims.
Are you sure about that? I did mine last year, and IIRC, thicker shims prevent the hub from pulling the inner and outer bearings together, so a narrower one reduces the endfloat. I am very possibly confused about this, but I did manage to remove my excessive endfloat and pass its WoF using the method described.
The JLM-409 will thread onto the earlier XJ6 racks. It is actually a nicer tie rod as the inner knuckle rotates in nylon so virtually no play. Earlier tie rods are shim adjustable and wear when there is any play which makes it hard to get them snug without play. The threads for the tie rod end and lock nut are metric so a later tie rod end and nut will be required. Other than that, the same lock plate JLM-172 is used to lock the tie rod onto the rack shaft.
Adjust the large nut with the grease nipple. Make it only so tight that it is still smooth and make sure you still have full travel. Check the two joints in the lenksäule for play.
The shim goes between the bearings inner races, so a thinner shim would reduce end-float.
Best, and more accurate, is to remove the hub from the car and measure play on the bench with a dial micrometer, no fancy tools needed.
As you need to remove the shaft from the hub to change/adjust the shim, I would invest in a set of new bearings as well.
As others mentioned, new bearings might bring the end-float to spec with the existing shim.
But again, being tapered bearings, I would recommend setting them at zero to a slight pre-load.
You can easily measure preload with the help of a luggage scale.
Depends on what ‘simple micrometer’ you have got, Jochen, but you need something that can measure horizontal, in/out, difference of the hub position…
You need to measure the difference in hub position, ‘in’ and ‘out’ relative to the hub carrier, and a ‘dial’ gauge can also show the actual motion. The spec motion being 0.002" to 0,006" gives some leeway; in theory measurable by a feeler gauge, but such a set-up is complicated and inherently imprecise…
The thickness of the existing shim is easily and precisely measured with a ‘standard’ micrometer - but you need both for deciding new shim thickness. And even done well; you may find things awry when retesting after new shim fitted…
Adding that the increased play may also be caused by wear, or whatever, of the bearings themselves which cannot necessarily be remedied by shim replacement. Requiring bearing replacement - which means carrier dismantling. But you know that of course…
I think what you need is a Dial Test Indicator (or DTI) rather than a micrometer in the first instance.
Clamp it to the aluminium hub body with the button on the back of drive flange as illustrated here and lever the flange back and forth to measure displacement (bearing clearance).
From memory the clearance to aim for is 0.001" to 0.003" but the ROM will say.
You may need a very strong puller to remove the hub as splines are usually coated in loctite like stuff on assembly.
I was lost about that spacer, sorry Kevin. You’re right - shaving the existing spacer should get me going again. Other than that, I’ve followed the advice and ordered a new Timken bearing. The pic with the DTI is very helpful!
As for the steering rack, I do have the gasket kit (see how far I will get) and have ordered JLM 409 with the respective ball joint. Now I’m curious whether the inside part fits the rack. The friendly guy at my suppliers helpline wasn’t sure either.
Unfortunately, I’m quite busy now and will get to tackle the thing only in two weeks:-(
