Bent stub axle front left

[Euler]

I was replacing my front rotors when I noticed the left front rotor was hitting the splash guard and wearing through so much that is touches the carrier (see image). The old rotor does not seem to be warped as there is contact as I turn it 360 degrees. Can this be anything else other than an bent stub axle? Just loosening the nut didn't release it - I'll need to find a slide hammer and risk damaging the nut and stub axle, so I'd like to hear if there are any other ideas out there as to what can cause this clearance problem.

left front axle 65 S-type rotor rub on guard at 12 oclock

IMG_1662.JPG (2.3 MiB) Viewed 1974 times

[JCS]

Euler
You may well have a bent stub axle, or even one on which the inner wheel bearing has spun and damaged the stub axle; I came across a similar foul situation caused by other components.

In my case I have an XJ steering rack conversion and although it is rarely, or never mentioned, this means the original steering lock stops are dis-guarded. In that case the geometry of the steering / suspension allows potentially the rotor (disk) and dust shield to foul on full lock unless a new lock stop arrangement is fitted. That situation can be avoided if the dust shield is removed or is trimmed, HOWEVER there is then a very strong possibility that the end of one of the bolts clamping the top suspension joint will contact the rotor on full lock.

The potential to result in a foul condition is dependent upon the spacers fitted each side of the top joint to control the castor angle. It is just possible to obtain the correct castor, trim the shield and avoid the end of the top joint bolt.
In order to check the clearances it is necessary to support the suspension in its normal position and envisage potential contact as the suspension moves through its range whilst the steering is taken to left and right full lock.

Normally you would not expect major fouling conditions to occur after changing the castor angle but I can assure you that is the case with this suspension when a rack is used. Unless the top joint is viewed from above, with the road wheel removed, and the steering moved to full lock this foul condition is unlikely to be seen. The dust shield covers the offending area from below…….and if you have experienced a light squeak or squeal near full lock check for this foul condition.

I fortunately have a four post lift, travelling jack and a Dunlop optical gauge and some time ago I spent some hours experimenting with castor spacers to examine this problem.

I suggest that you check the castor spacer blocks and see that they are roughly equal on both sides of the top joint and ensure the shields are secured firmly.

Although this problem has come to the fore by increased steering lock after having rack and pinion steering it might occur if original lock stops are not adjusted correctly.

Norman

[Glyn Ruck]

Lock stops. S Type PAS. Beefed up drop and idler arms over manual items.

lock stops.JPG (75.38 KiB) Viewed 1946 times

IMG_20180722_165324 (2).jpg (595.54 KiB) Viewed 1946 times

[Euler]

Many thanks to both Norman and Glyn

I will definately check the lock stops and shims, but I should have emphasized the scraping of the shield lower down in the photo - over the right part of the stub axle carrier. That clearance doesn't seem to be effected by the castor angle. Yet worth checking out. I have new rotors that I will test fit to see what clears and what doesn't, and calipers from Coopercraft are on the way. When this gets figured out, I'll re-post.

I probably should have pointed out on my first post that the shop I used to get the front brakes rebuilt, just after I bought the car last year, replaced the calipers such that the inner pads seemingly never touched the inner side of the rotor. Except for the scrapings on the left, both inner surfaces of the rotors looked pristine. Glyn pointed out in a prior subject line about leaking calipers, that it could have been a caliper piston problem, but I am fixing this problem by replacing with Coopercrafts.

Again, thanks-
Roger Young (Euler)

[Euler]

Thought I'd provide an update.
I tried to gracefully remove the stub axle with a bit of help from a slide hammer. but after a few medium forceful hits, decided I was more at risk for damaging things then fixing things, so I rethought the whole process. The stub axle itself looked good after I took off all the grease, and the bearings seemed to seat nice and firmly.

It now looks like the problem was caused by a series of events. First, the steering is not stock - there are no steering stops - and the unit that is on there doesn't look like it can accept any stops either. Hence, over time, the rock guard repetitively fouled between the disk and the upper axle carrier bolt. This caused the guard to pull away from the mount at the caliper and essentially wrinkle a bit. The guard then fouled between the disk and the right rising part of the axle carrier.

So - I straightened out the guard and got some clearance with the carrier. I am now awaiting arrival of new coopercraft capilers and I'll try to put the whole thing back together with better shimming of the calipers. I'll check the camber, but best I can tell with an unsupported coil, the camber is 0 degrees. Before I put the guard back on I'm going to cut out a small piece to clear out the spot where it was rubbing. I'm thinking about manufacturing a soft aluminium "tell" that will sound when the rotor hits it, but won't damage much. Alternately, I'll have to get creative with some steering stops
Roger

[JCS]

Euler

You will need to trim the dust guard if you are fitting Coopercraft units, but you will find them very good and not regret fitting them.

As a matter of interest what thickness are your rotors (discs)?

I think you will need to get creative with some stops, so will I, as I need to do the same on my car.

Norman

[Euler]

I just got a pair of the the Moss C27024 standard rotors.

I am having a bit of a problem hooking up the flex hose to the coopercraft calipers, though. The instructions seem to indicate doing strange things.
Roger