steering rack set up

[cadetchris]

Whilst i am waiting for the sprouts to finish boiling, I thought I would ask a question that has been vexing me for some time.

I have totally disassembled, cleaned and reassembled the steering rack (as well as stripping and cleaning of the front suspension) and I am not having issues setting up the rack so its back to normal. So, how do I reset the rack back to its centred position? from which I can then do the tracking of the front wheels, but I just cannot get the thing centred properly.

Do I have to whip it off the car, remove the rubber bootings and count teeth on the rack to ensure its exactly centred or is there another method I am not aware of?

[Steve Phillips]

Simplest method I know is position the rack roughly in the centre position, its easiest if the boots are not fitted because you can see that the rack is roughly centered, but if they are then push it all the way away from you (from under the arch) take a measurement the pull it all the way towards you take a second measurement and halve it, it will now be somewhere near the centre, now loosely fit your steering wheel so its centered,

Now sitting in the drivers seat turn the steering wheel all the way left then all, the way to the right (or right then left whicher takes your fancy) but which ever you should end up with the steering wheel equally rotated to both the left and right when on full lock both ways,

So for example if you now find the wheel ends up 90 degrees to the left on full left turn and 100 degrees to the right on full right move the steering wheel 1 spline to the left, then repeat the turning left and right on full lock until the steering wheel is the same amount out of centre each way, sometimes you will find you can't get a perfect equal on a production vehicle, but if its within one spline it will be good enough,

Steve

[newagetraveller]

When the track rods are correctly adjusted, exactly the same length of thread should be exposed on each side.
Then I fit the steering wheel to roughly the right place, drive in a straight line, stop and centre the steering wheel.

[cadetchris]

Excellent, thanks for the tips. Once the car is back on 4 wheels, I’ll give it a bash and hopefully that will bring it back into line.

[kevin s]

I do it from the drivers seat, turn the wheel full lock one direction, mark the top on a piece of masking tape, turn it full lock in the oposite direction and do the same, now turn it roughly to straight ahead, or count half the number of turns lock to lock, with the centre point between the 2 marks you have just made at the top the rack should be centred.

[Sleeper]

+1 the above...

John ;-)

[cadetchris]

Right, slight issue.
So if I pull the rack so it’s fully extended on the passenger side, it comes to 12.6cm , so logically if I half that to 6.3cm I’ll end up with 6.3cm at the drivers side, thus the rack is centred.

But I don’t.....

I get 6.3cm on the passenger side and 5.45cm on the drivers side.

I’ve got the whole rack off, track rod ends off and rubber gaiters off too, so I should be able to get it rather accurately, but the difference in measurements has thrown me slightly.

[cadetchris]

I must also add, if I pull the rack all the way out on the drivers side, I have a length of 12.6cm and halving it gives 6.3cm on the drivers side 5cm on the passengers side, so which end do I rely on the rack being centred?

[kevin s]

If the rack housing isn't symetrical (ie the pinion housing is larger) you won't get the same amout sticking out of each side at straight ahead would you?

[cadetchris]

That’s what I thought too.

I consulted the workshop manual and it appears I have to count teeth on the rack and centre number 12 in the pinions hole. I’ve done that and whilst it’s not perfect by any stretch, it’s better than it was.

As the car is just being pushed in and out of the garage, I’ll leave it at that and fine tune it when it’s ready to go on the road again.


Whilst I’m here and out of curiosity, are the track rod arms both the same length?
If not, then it would be useful to know that now and not when the engine and gearbox are back in the car.

[cadetchris]

That’s what I thought too.

I consulted the workshop manual and it appears I have to count teeth on the rack and centre number 12 in the pinions hole. I’ve done that and whilst it’s not perfect by any stretch, it’s better than it was.

As the car is just being pushed in and out of the garage, I’ll leave it at that and fine tune it when it’s ready to go on the road again.


Whilst I’m here and out of curiosity, are the track rod arms both the same length?
If not, then it would be useful to know that now and not when the engine and gearbox are back in the car.

[jaekl]

There is a score line on the end of the pinion. If it was assembled correctly, it will point up when the rack is centered, but it's not crucial. You only measured the length the rack extended on the passenger side. You need to do that also on the drivers side. Then half the average of the two to set the center. Then align the steering wheel at this point. Now you can adjust the tie rod ends to get the wheels point straight while maintaining the position of the steering wheel. Based on what you stated, the tie rod ends are not equal and that is why the rack extends more on one side than the other. Whether the rack is symmetrical or not doesn't matter. The travel from stop to stop is and that is established by the inner ball joint hitting the end of the housing, which probably is symmetrical.

[cadetchris]

I’ll have another look tomorrow, hopefully it won’t be as cold as it was today.

[les]

I guess someone would have picked up on it by now, if I was right but I had the notion that there was a small hole in the outer housing and one in the rack, that when lined up, using a pin, gave you the correct position. Maybe I’m thinking of another application.

[Michiel]

I guess someone would have picked up on it by now, if I was right but I had the notion that there was a small hole in the outer housing and one in the rack, that when lined up, using a pin, gave you the correct position. Maybe I’m thinking of another application.

Yes ForJaguars XJ and XJS remove the grease nipple, insert a 5 (I think) mm drill and when that slides in to a hole in the rack it is centered. Same trick with bellhousing and flywheel of a Citroën 2CV, but then you have TDC