Rear toe setting

cobraboy

Well-Known Member
Evening all.
Have string lined the car and found that the OSR has some toe in, NSR is straight ahead.

Any one have an idea on how to correct this ? I can only think of shimming the rear hub to elbow, but with 6 bolts it wont be easy.

Cheers for any pointers.
 
I can't think of any way that provision for adjustment was built in, your idea to shim the hub would work, but you'd need a pair of tapered shims, one on the outside one on the inside, but I think I'd look elsewhere for the cause of the problem first. If the car has been kerbed the elbow or the trailing arm could be bent and that could cause it.
 
I had a similar problem. Too much toe out at the rear. Of course as Harvey says, the first attempt should be to replace the bent parts, elbows or DeDion tube, but as i hadn't access to replacement parts, the alignment shop shimmed the hubs to elbows. It was a trial and error procedure, but in the end we got there, and i have never had any problems since.
 
Thanks chaps
I don't think it will need much at the hub to make it come right at the wheel so trying to find a tiny miss alignment in an arm or elbow will be nigh on impossible. I don't have any other parts to swop in.
I will give it a looky and see how much it needs at the hub then have a think on how to go about it.
I remember years ago I had a rear tyre on an Astra van cutting out on one side, this had a beam axle and the hub was on four bolts, I put washers between hub and beam on two of the bolts and it came spot on and never wore the tyre again.
Harvey, I wondered if there was a wrinkle from back in the day ?

Thanks all
 
I don't think that the arms could affect the rear wheel alignment. It is all down to the tube and elbows. And although it is rather easy to check the tube for straightness, this is more complicated for the elbows. For someone determined, i guess it could be possible to correct the bent part. However, this is way too complicated compared to just shimming the hubs. My car was rather tired and maltreated from the previous owner, so i guess this is where the damage came from.
 
If the trailing arm was bent it would effectively be shorter, pulling the elbow toward the front and toeing the hub inwards in my mind..but if the de dion was still sound and perpendicular the other wheel would then be toed out surely.

For some reason this has reminded me of a car years ago which had a failed diff mount or two. When taking off, the rear wheels would lurch forward an inch or so, in reverse it would do the same lurching backwards. At the time I couldn't get my head around how a fixed structure was moving like that, and why the independent diff mounting would have an effect.
I'm sure I remember the diff mounts correcting it, but it still doesn't make sense to me.
What makes sense is if the upper arm top mounts were moving and the de dion was actually rolling forward and back in an arc with the drive torque, moving the wheel location

Sorry for the "tangent" :D

Take up circle racing?

Jim
 
I am determined that this will not have me going round in circles :D
Diff mounts, lower arm bushes, upper link bushes, crossmember bushes, are all fresh.
Elbows have been thoroughly inspected with the lower arms off and then waxed up. If I thought there was a serious issue with a component then I would not hesitate to replace it.

Cant lose any sleep over it, car has probably been slid into a kerb or something in the past and sustained a knock. Tis only out a small amount so shimming will sort it.
I only put string down it as I am going to be doing some work to the front to improve a steering issue and wanted a base setting.

Jim if you want to borrow the string when I am done you are more than welcome, I'll leave it set for a left turn track :p
 
Haha, the string probably needs to be recalibrated!
Did you check it was twice as long as one end to the middle?
:D
 
Yup indeedy thanks.
This afternoon got it straight, 2 x 0.030" washers at the front, zero at the back and then inserted horse shoe shims made from brass shim stock to take up the gaps in the others and the job is a good in.
Cant believe all the bolts came undone, the worst part was having to glue the nuts to the washers to get them back on, bit fiddly. Have now retired for tea and medals - a good day.
 
This afternoon got it straight, 2 x 0.030" washers at the front, zero at the back and then inserted horse shoe shims made from brass shim stock to take up the gaps in the others and the job is a good in.

Only time will tell of course, but I reckon the hub's going to start moving on the elbow.
 
The locating register is still sited in the elbow, I have not pulled it out so far that it is solely relying on the bolts. I will keep an eye on it. Thanks for your thoughts.
 
My worry would be that you're now holding the hub on with 6 5/16" bolts loaded in tension, with just a fraction of the clamping area to resist shear. At the very least I'd think about replacing the bolts with grade 8 or better and filling the gap with some kind of faying compound that sets up hard.

Yours
Vern
 
As per Demetris' post above I am not the first person to have to deal with this. Yes ideally there should be a replacement part to swop in, but one cannot pop down to the local Rover dealer and pick up an elbow any more. I am reluctant to buy an unknown part off ebay.
I am always ready to learn and take advice so keep the dialogue coming, there must be a solution for this that works and I am quite happy to listen.
I had thought of changing out the bolts for 3/8" high tensile to provide a bit more clamping. Perhaps it seems a bit more drastic thinking about it than it is in real life, the Rover is so over engineered anyway that compared to modern stuff there is no way the thing is going to fall off.
I am also mindful of the much wider rubber I have fitted and the increased loading from that, so perhaps I had better do some stress testing on the hub at my local airfield ;)
 
I am having second thoughts on this, and it seems that if someone has the tube and elbows bolted tothether out of the car and on the bench, it is very easy to measure for squareness and adjust accordingly. So this is probably a proper long term solution without having to swap parts.
 
As anyone any idea what the toe should be on the back , I cannot find any published data? The assumption above seems to be that it should be zero.
 
Demetris
I can see putting the tube on a surface plate in some V blocks then squaring up from the plate to the hub mounting faces would work, but alas that kit eludes me. If an error is found then elbow replacement is likely.

I know the elbow is probably at fault, hey it might even be within factory tolerance ? How many of you have had a four wheel alignment ? If your tyres are not wearing uneven would you give it a second thought ?
I don't have any tyre wear from this but I would like to get it sorted one way or another. Speaking with learned friends today the impression seems to be to fit some decent bolts tightened to FT and monitor for a bit.
 
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