Suspension Adjustment to try and stop the car wandering

[Martec]

Sometime ago I used a few heavy duty screwdrivers to see which bushes were knackered and so were causing the wandering on main roads above 60mph. Only the front lower wishbone front 'Hydraulic' bush seems to have a lot of movement, but there were no thumps or bumps over rough roads.

I read of XJK and their state of the art alignment gear, so being cheeky I emailed them for advice, below is their reply.

''If you are happy that there is no play in the suspension then there must be an issue with the set up of the alignment. Yes you are correct toe in is a positive reading and toe out a negative. You can adjust the rear toe but not rear camber (no caster angle on the rear as its used to self centre the steering wheel). First of all if the vehicle has not been aligned before on this age of vehicle is not fitted with adjusting bolts. The steering rack will have to be dropped and adjusting cam bolts fitted to both the front lower suspension arms. Currently you will have standard bolts in slotted holes.''

I used the suspension spec to find the limits, but Ian Kelsall included these in his email reply anyway, there is a difference between pre and post 2002.25 (surprise!!).

I borrowed an old tired 'Dunlop' alignment setting tool from a friend (he offered his 4 wheel alignment gear but I don't know how to us it). After recalibrating the 'dunlop' gear I tie-wrapped a laser to a straight edge (two leveling devices together).

At the rear the toe in was too much and off to one side, so using the adjustable tierods I moved the rear wheels to less toe in and central( dunlop gauge to give total toe in and the straight edge lying along the tyre and the laser shining on the front tyre to give central position). Camber was within limits (I couldn't find my home made measure so used a small(9") level on a piece of wood and measured the gap at the top.

The front camber was out, passenger wheel was OK. but the drivers wheel was 1 degree negative camber (mid point should be 0.1 deg neg.). So I slackened the rear bolt of the lower wishbone and using a small screwdriver levered it in in by 0.25" (all very slack and easy) and bolted it up tight. This will affect the caster a little, but the toe in also had to be reset, again to mid range and central (steering wheel central when driving, but is not tooo critical as I don't have 'Dynamic stability control').

The car needed driving up and down the road to let the suspension to settle to get accurate!!!!! readings. I also raised the tyre pressure up to 'normal spec' of 32/34psi. So far the car feels better on the motorway if a little floaty, but less steering correction but time and the journey to Brum will tell.

This is obviously not on a par with the sophistication of XJK's gear and expertise, but I think is an acceptable home made effort. I'm still looking for a broken 'dunlop' gauge to repair for myself. I recently had my garage floor relayed to my levels so can rely on a level surface.

I have also replaced the 'spacesaver' thing with a classic alloy wheel and a part worn unidirectional tyre(£57 total) and have now packed the centre with jack and tools.

Brian

[oldtimer]

Hi Brian,
Have read through the above twice but I am struggling to understand as I'm not that familiar with the S geometry - older stuff ok

I read that you intend a test drive from Sunny Scunthorpe to Brum on Saturday, would that be to a certain Seminar? If my presumption is correct then I shall see you there. I have decided to do a night stop next door to avoid an early start.

Regards Phil

[J44EAG]

I`ll be there for bacon butties by 08.30am. I like the early start and traffic free conditions at that time in the morning.

Look forward to seeing you chaps there.

I`ll not guarantee a clean car. J44 is a working car and it tends to show nowadays.

Mike

[oldtimer]

Snout out the window and follow the scent ah Mike

[Martec]

Yes I'll be at a certain seminar so look forward to meeting you all nodoubt with a dirty car as well............are you supposed to wash them!!!

I asked Ian Kelsall of XJK if he would be including something about the 'hyraulic' bushes in his talk but he said he hadn't written it yet!

Brian