Whenever the tie rod or any ball joints are replaced, the alignment will need to be set and that is where you may need to throw yourself at the mercy of a professional.

The steering on the recently bought red car didn't feel right and I decided it felt like it had too much toe out. The self centring was vague and it wouldn't stay in a straight line with hands off the steering, it would pull to one side of the other. Took it into a place I've used before and told them they didn't need to worry about the steering wheel alignment as I could do that myself, it was purely the adjustment of the tie rod that needed doing. Unfortunately they have a newer alignment system than they previously had and a technician who wasn't familiar with the steering box type system on the P38. Firstly he wanted to adjust the alignment on on the rear which, as I pointed out, will be correct unless I have a bent axle. Both wheels are going to be pointing the same way obviously. Once he had got his head around how it worked, he realised what he needed to do. Only to find the adjuster was rusted solid. After struggling with it for almost an hour, he gave up and told me that if I could get it freed off, I could bring it back and he could adjust it.

But, as I was about to leave, an older member of staff suggested an alternative method. If I was to use a laser tape measure and measure the distance between the rear and fronts rims of the front wheels that would tell me how much toe in or out I had. As it happens, I've got one of these https://www.amazon.co.uk/Measurement-131ft-40M-Rechargeable-Pythagorean/dp/B0D7PYSRQT/ref=sr_1_22_sspa, so tried it. The front wheels should toe out by 0.6 - 1.8mm. Checked it and found they were toeing out by 4mm! Checked my car, which tracks perfectly, and found it appeared that the wheels had neither toe in or out, but the laser tape measure only goes down to a millimetre so I wasn't able to see if they really were parallel or slightly toeing out as they should but it gave me a target to aim for.

Freed off the adjuster (Plus Gas, heat and a 24" pair of Stilsons), took it right out, cleaned up and greased everything then started. By measuring the difference between the rear and front of the front wheels, I got it so the distance was the same, then gave the adjuster a 1/8th turn in to give it a bit of toe out. That gave me a difference of 1mm, smack in the middle of the setting.

A quick road test showed that the steering wheel wasn't central when going straight ahead. Checked the centre marks on the steering box and that wasn't centralised when steering straight ahead so adjusted the drag link. With the steering lock off and the wheel in the position where it was when going straight, as you adjust the drag link, the steering wheel will move so once it is straight, the job should be done. If the steering box is centralised but the wheel isn't, then it needs the steering wheel moving on the column so they are both central.

A proper road test showed that now the wheel is central when going straight ahead, it self centres properly when straightening up and drives in a straight line with hands off the wheel so that's another job ticked off the list.

Sounds like a reasonable way to get close enough. Interestingly most of the Amazon brands quote 1/16" accuracy, whereas others like DeWalt, Stanley, etc. all say +/-3mm.

Makes me wonder how accurate the tyre centre systems really are ?

The cheap one I have is normally used to measure the size of a room when working out what size AC unit it needs (volume of room in cubic feet x 5 = Btu of the unit required, the same calculation is used for heating) so it doesn't need to be perfectly accurate. Same with checking the wheel alignment, you aren't looking for an absolute dimension, just the difference between the measurement at the front of the wheel rim and the back.

I suspect the tyre centre systems are as accurate as the man that attaches the sensors to the wheels. They gave me a printout of what it thought mine was. It showed 2.1mm of toe IN on the front, when my measurement showed it was toeing OUT but more interesting it showed my LH rear wheel having 8.1mm of toe in and the RH one having 2.9mm toe in. Quite how you can have a total of 11mm of toe in on a solid axle I've no idea and suspect the sensors weren't properly seated on the wheels. The phrase 'all the gear and no idea' springs to mind.

Unless the axle housing is bent, I’m pretty sure you can’t have any toe in or out on the rear axle.

Harv wrote:

Unless the axle housing is bent, .

Can't see how it can bend !! Isn't it a casting ?

I have also had guys with no idea how to setup a steering box system, or why he couldn't adjust one end of the track rod !! Luckily I found another place nearby with an older & wiser alignment guy.

Yes it is, and I may have found all sorts of bodgery that has been done to this car but I can't see an axle being bent, particularly not that much!

there is only 2 adjustments on a rover
align the back wheels with the front wheels so the track is right , this is done with the Panhard rod at the front
and the toe in or out with the front steering arm thats between the wheels
straighten the steering wheel with the arm of the steering box
if you don't have a laser for measure, you can put a chalk mark on the back side on the tread of the tyre , measure and roll forwards 180deg and measure the front to get the toe in or out. this is a little crude, but it will get you in the ballpark so to speak
some of the alignment equipment is very accurate to the point 0.1mm
just a note, there is no adjustment on the back axle, if the axle will not align you most likely need new bushes fitted.

But there's no adjustment on either of the Panhard rods? The Panhard rods cause the axles to move from side to side slightly as the car rises and falls on the suspension but they both move by the same amount relative to the chassis so always remain parallel with one another.