wheel alignment/tracking

This is the Forum for all your Citroen Technical Questions, Problems or Advice.

Moderator: RichardW

deian
Posts: 1729
Joined: 26 Feb 2006, 11:53

wheel alignment/tracking

Post by deian » 21 Mar 2006, 19:59

I took my car to ATS Euromaster yesterday to get the tracking done £23.50 for 4 wheel laser tracking!

As it was before I took it in, the steering was just not in the middle, a bit to the right, not pulling. I left it there while i was at work for a few hours.

First time they messed it up, it's like the guy adjusted it the wrong way, the steering wheel was more to the right and pulling to the left upon centering, and it felt light! I was fuming, so today after work I took it back...

Credit where it's due... this other guy who did it today said the guy yesterday was crap, so he had a go, and i stood there and watched him doing it. And it was better, he got it corrected, tighter, straighter, but i can't help but feel it's still not good enough for £23.50. The steering wheel is a few degrees to the left now, but doesn't pull in anyway. SO is ATS crap, not heard good things about them locally.

Anyway what i want to ask here specifically about the mark2 xantia is: is there anything 'different' on a Xantia that can give a false reading or make the job harder on a 4 wheel laser tracking?

(tyres are all evenly worn, all up to correct pressure, and there is no madness ofthe steering/suspension components).

Is it easy enoguh for me to do the final tweaking myself. It's not hard at all really is it, a couple of hours with a spanner and my tracking dream can come true yea?

Any comments would be great. Thanks.

citronut
Posts: 10939
Joined: 29 Apr 2005, 00:46
x 3

Post by citronut » 21 Mar 2006, 20:31

your best going to a small company rather than a big national,they might have checked it with it up on the highest susp setting,why was it out in the first place
regards malcolm

deian
Posts: 1729
Joined: 26 Feb 2006, 11:53

Post by deian » 21 Mar 2006, 21:05

they didn't touch the suspension settings, i doubt they even knew about the suspension type on a xantia, even if they do, I doubt they know enough about,
i only got the car 2 weeks ago and it was like that
... i just CANNOT stand little annoyances, tracking included! I'm sure many agree with me. Everything HAS to be perfect, hence all the fiddling on the way to perfect my machine.

User avatar
Mandrake
Posts: 7790
Joined: 10 Apr 2005, 17:23
x 194

Post by Mandrake » 21 Mar 2006, 21:47

Hi,

If they didnt know anything about the suspension there is a possible problem right away - the suspension MUST be accurately (+/- 10mm) at the normal ride height to get an accurate wheel alignment.

This means they must leave the engine idling, and try to avoid getting in and out of the car during the test/adjustment to avoid the height corrector making corrections. If they don't know anything about Citroen's you need to point this out to them.

Secondly, if the steering wheel centering has changed, it means they are not adjusting the tie rods equally. If they want to increase or decrease the toe out, they should be making equal adjustments on both sides. If they only adjust one side it will alter the steering centering. They should be taking the car for a quick drive around the block after an adjustment to confirm the steering wheel centering is correct, and that the self centering feels right, if not they are doing a crap job.

Thirdly, did you get a printout with before and after measurements ? Make sure they are choosing the right car otherwise they may be setting it to the wrong parameters. If they don't have the exact model listed in their computer, they may be unsure which is the closest match. Xantia's use toe out, not toe in like some older cars.

If the steering is too light they have probably reduced the toe out too much. The place that set mine reduced it from -2.5mm to -0.9mm and I noticed the steering got significantly lighter, a bit lighter than I prefer but still ok.

If the self centering from full lock turns is really crap now then they may have even set it mistakenly for toe in instead of toe out.

The correct parameters for your car are:

Toe out 0 to -3mm, Caster 3deg +- 30min, Camber 0deg +- 30min, KPI 13deg 15 min +- 35min. Only the first one is adjustable, the others are just checks to make sure there isn't some alignment damage in the suspension somewhere...

Also have you got your new tyres yet ? You really should get the wheel alignment done on the new tyres rather than old, as new tyres with new tread tend to give better self centering for the same toe out amount.

Also, you mention pulling to one side while driving - wheel alignment can't really cause that, and unless there is a geometry problem in the suspension due to a prang, there is most likely something uneven about your left and right tyres, such as uneven wear, so you may be throwing your money away trying to get wheel tracking perfection on the old tyres...often you can't visibly see any difference between the tyres but there will be something about them that will affect pulling to one side.

Finally, I get the impression that many wheel alignment places, upon being presented with a car which has nothing wrong with the alignment, will then deliberately change the toe out (add more if it doesn't have much or reduce it if it has a lot) even if it is well within spec and then charge a normal price when they should have really just decided it didn't need fiddling with and charged a simple checking fee. (EG, they feel a need to justify their charge) So beware.

Because of this its important you tell them why you're taking it in - in your case you wanted the steering wheel centering fixed, there was probably nothing wrong with the amount of toe out it had before.

Sounds like you need to try somewhere else, unfortunately you probably wont get a refund... :(

Regards,
Simon
Last edited by Mandrake on 21 Mar 2006, 22:09, edited 1 time in total.

deian
Posts: 1729
Joined: 26 Feb 2006, 11:53

Post by deian » 21 Mar 2006, 22:08

This is ATS Euromaster we're talking about, one of the big chains in the UK. They left the engine running and took it up on a lift. Anyway little by little i will do it myself, until i'm happy. I'm not scared. I'm 99% certain the car hasn't had any prangs, it's in a very good condition, and i had a good look at the suspension components on sunday (before taking it to get tracking done), they all looked spot on. If one wheel points out and the other straight then wouldn't that make it pull out?

jeremy
Posts: 3959
Joined: 20 Oct 2002, 16:00

Post by jeremy » 21 Mar 2006, 22:11

Nice and simple to diagnose. I bet if you mark the centre top of the steering wheel as the car is at the moment and then turn the wheel to full lock on one side - note the position of the mark and do the same the other side you will have found your problem as the mark will show that the wheel is turned more one way than the other.

The problem is that the rack itself is not centred. It is common for this to be hidden by the steering wheel being replaced aparently straight. The result is that while the wheels appear correctly aligned when straight, as soon as the steering is turned it all goes wrong and the thing will feel very strange.

Cure - centre the rack first, refit the wheel straight, then do the alignment both sides - and suddenly you will have a car that steers the way the manufacturers intended.

Finding someone who knows how to do it - well that will be fun!

User avatar
Mandrake
Posts: 7790
Joined: 10 Apr 2005, 17:23
x 194

Post by Mandrake » 21 Mar 2006, 22:18

deian wrote:This is ATS Euromaster we're talking about, one of the big chains in the UK. They left the engine running and took it up on a lift. Anyway little by little i will do it myself, until i'm happy. I'm not scared.
Do the adjustment yourself ? How are you going to measure it ?
I'm 99% certain the car hasn't had any prangs, it's in a very good condition, and i had a good look at the suspension components on sunday (before taking it to get tracking done), they all looked spot on.
Ok
If one wheel points out and the other straight then wouldn't that make it pull out?
Not on a car like a Xantia with conventional power steering, no. Because the power steering itself has no self centering - it relies on the self centering torque from the wheels to centre the steering.

So if it was adjusted so that the left wheel was pointing too far to the left, what you end up with is not pulling to the left, but instead the car will still find the straight line properly, but the steering wheel will now be slightly to the right, and you will have slightly too much toe out.

What CAN happen, which I forgot to mention, is that large amounts of toe out (close to the 3mm maximum) gives a very strong self centering action which can disguise any tendency for the car to drift sideways due to unequal tyres, or slack in suspension balljoints or in the steering balljoints, as the self centering torque keeps up the slack in the joints.

Reduce the toe out, and now the slack in the joints can start to play during straight ahead driving, and the car may drift off line - usually in the direction the road leans.

You'd need to look at the printed out report to see the before and after toe out to see if this is what happened.

And as I say, it could be the tyres, so trying to get straight line tracking perfection on unknown fairly worn tyres is probably a waste of money.

Regards,
Simon

User avatar
Mandrake
Posts: 7790
Joined: 10 Apr 2005, 17:23
x 194

Post by Mandrake » 21 Mar 2006, 22:22

jeremy wrote:Nice and simple to diagnose. I bet if you mark the centre top of the steering wheel as the car is at the moment and then turn the wheel to full lock on one side - note the position of the mark and do the same the other side you will have found your problem as the mark will show that the wheel is turned more one way than the other.

The problem is that the rack itself is not centred. It is common for this to be hidden by the steering wheel being replaced aparently straight. The result is that while the wheels appear correctly aligned when straight, as soon as the steering is turned it all goes wrong and the thing will feel very strange.

Cure - centre the rack first, refit the wheel straight, then do the alignment both sides - and suddenly you will have a car that steers the way the manufacturers intended.

Finding someone who knows how to do it - well that will be fun!
Hi Jeremy,

I suspect this isn't the problem in his case, however you may have described the problem with my Dad's Xantia.... there is just something wrong with the way it steers, and it HAS been in a prang, and I didnt even think about the rack itself being out of position.

How can that be measured ? And what kind of position mounting does it have ?

Regards,
Simon

deian
Posts: 1729
Joined: 26 Feb 2006, 11:53

Post by deian » 21 Mar 2006, 22:40

no sign of computerized readings here, so no before or after printouts! and i didn't see them read any documents for computers for specifications to work against.

they use a laser on both the front wheels and line it up with the back wheels, it's that simple,
whether the 'trained' mechanic can read the laser/guides and adjust accordingly is another issue. they don't even take the car for a test drive before releasing it back to the customer.

i myself am confident there is nothing wrong with my car, except bad workmanship over the last two days and before that the usual wear and tear that gives the need to for 'wheel alignment',

i won't be measuring with any special tool, just on the end result, if it drives straight with steering in the middle then i'll be happy,
but if i can't achieve my 'tracking perfection' i will give up and assume there IS something else wrong, in which further investigations will begin.
My tyres aren't too bad, plenty of evenly worn tread on both sides, it's just I will buy a complete set of Michelin Energy towards the end of summer.

Thanks

jeremy
Posts: 3959
Joined: 20 Oct 2002, 16:00

Post by jeremy » 21 Mar 2006, 22:47

Simon - in fact generally you'll find that the real problem is simply that the tracking has been adjusted from one side and hence the rack is out of position. The marked steering wheel test gives a good idea of the problem without getting your hands dirty and indeed I got a substantial improvement on my BX using that method of measurement only.

What you are hoping to do is to find the centre position of the rack. Haynes says peel the gaiters back and measure but many of these gaiters don't peel back easily so another method must be found. I don't see any reason why the measurement shouldn't be made from one side - so if the rack is extended fully to one side and the trackrod end is placed against a suitable marker such as a pile of bricks or whatever is handy, then wound the other way and the distance measured - then the centre should be half the distance.

having established the centre the rest of the steering must be set up without moving the rack. probablt the best thing to do is to fit the wheel after centreing the rack - so that the centre can be found again easily - then do the track rods.

I appreciate that you appear to need a sophisticated gauge to ger the trackrods and hence the wheels accurate but in fact its not very difficult to sight this by eye correctly. Simply look accross the edge of the front tyre and look at the back wheel. get it the same for both sides, with a small amount of toe out then start measuring and you'll probably be right. If you've got a laser pointer it will probably be a bit easier.

Measuring the tracking can even be done with a tape measure. I've done it with 2 blocks of wood about 15 inches long. You would like to lay this on the ground and measure the front and back distances accross the front of the car. As the tyre bulges you need to fit 2 pads to each to get it to fit properly and avoid the bulge. Obviously the blocks must be the same size for each side.

Bit tedious but it works!
tight the

deian
Posts: 1729
Joined: 26 Feb 2006, 11:53

Post by deian » 21 Mar 2006, 22:57

i like your style jeremy, i'll give it a go this weekend, you do all this with the front off the ground, so u can turn the steering wheel without risking the friction of the ground giving false readings. ok so i may have lost £23.50 (it is SLIGHTLY better than before, but not good enough for me), lesson learnt, if u want something done, do it yourself.

jeremy
Posts: 3959
Joined: 20 Oct 2002, 16:00

Post by jeremy » 22 Mar 2006, 00:12

Deian - you can do the work on the rack with the car raised - indeed you will have to. The wheel alignment must be done with the car on the ground and at normal height both front and back. When you've got it right you should roll the car 1/2 a wheel turn and check it again - just in case a wheel or tyre isn't quite straight.

The car should be rolled before any wheel alignment measurement is made to ensure that there is no stres on the tyres etc which may give an incorrect result.

User avatar
Mandrake
Posts: 7790
Joined: 10 Apr 2005, 17:23
x 194

Post by Mandrake » 22 Mar 2006, 01:02

deian wrote:no sign of computerized readings here, so no before or after printouts! and i didn't see them read any documents for computers for specifications to work against.
Sounds a bit shoddy if they didnt give you a report. Any time I've been for a full body wheel alignment they always give me a computer printed report (done automatically by the machine that takes the measurements) which shows a full set of before and after measurements.

Also they punch the model and year of the car into the computer and it tells them what the "normal" figures are. The report includes what model of car they selected as the reference, and what the "normal" figures are for that model.

Otherwise how can they know what to set it to ?

Regards,
Simon

User avatar
Mandrake
Posts: 7790
Joined: 10 Apr 2005, 17:23
x 194

Post by Mandrake » 22 Mar 2006, 01:09

jeremy wrote:Simon - in fact generally you'll find that the real problem is simply that the tracking has been adjusted from one side and hence the rack is out of position. The marked steering wheel test gives a good idea of the problem without getting your hands dirty and indeed I got a substantial improvement on my BX using that method of measurement only.
Oh sorry, I thought you meant the rack mountings were out of position. As could be the case on a car that has had a smash. I'm aware of the possibility of setting the tie-rods to unequal lengths and then disguising it by moving the steering wheel on its splines... but good point, I will check that on Dad's car.
I appreciate that you appear to need a sophisticated gauge to ger the trackrods and hence the wheels accurate but in fact its not very difficult to sight this by eye correctly. Simply look accross the edge of the front tyre and look at the back wheel. get it the same for both sides, with a small amount of toe out then start measuring and you'll probably be right. If you've got a laser pointer it will probably be a bit easier.
A bit too crude for my liking :wink: Parallax errors are very misleading things, and if the geometry is out in any other way such as incorrect camber, or incorrect camber or toe in of the rear wheels you will end up in a right mess...
Measuring the tracking can even be done with a tape measure. I've done it with 2 blocks of wood about 15 inches long. You would like to lay this on the ground and measure the front and back distances accross the front of the car. As the tyre bulges you need to fit 2 pads to each to get it to fit properly and avoid the bulge. Obviously the blocks must be the same size for each side.

Bit tedious but it works!
tight the
Yep,

Been there done that back in the days of my GS, but unless you're REALLY careful your accuracy of measurement is worse than the required setting.

A measuring tape isn't accurate to a mm, because of droop, and inaccuracy holding it, especially on the rear edge of the wheel were access is difficult..... the way we used to do it was we made bar that was slightly narrower than the wheels, and each end had a little sliding clamp and on the end of that an L shaped rod that went up and could rest against the tip of the wheel rim.

The whole thing could be swapped back and forth between the front and back edge of the rim. Still fiddly, but a lot more accurate than a tape measure.

Regards,
Simon

dnsey
Posts: 1543
Joined: 20 Oct 2004, 01:39
x 14

Post by dnsey » 22 Mar 2006, 09:23

Just to add that to measure tracking properly, by whatever method, the wheels should be rotated 180 degrees between front and rear measurement, to eliminate any variations in the rims.