Front alignment

[John L]

I want to reset the front wheel alignment on my 5,  The steering arm inner rods have different lengths of threads showing at the track rod ends. There is a very useful item on the old classic mini, where you can insert a pin in the steering rack to get the steering centralised,  so my question is there such a thing on the TR's steering rack?  There are so many splined connections on the steering gear shaft, that will come into effect once the rack is in the central position. 

So is it purely a matter of setting the steering joints an equal amount on either side, and setting the tracking to parallel or slightly toed in, and then setting all the other splines to get the steering wheel and indicator notch into the right place?

Is there is a simple may to determine the rack central position mechanically?

John

[BlueTR3A-5EKT]

1 hour ago, John L said:

I want to reset the front wheel alignment on my 5,  The steering arm inner rods have different lengths of threads showing at the track rod ends. There is a very useful item on the old classic mini, where you can insert a pin in the steering rack to get the steering centralised,  so my question is there such a thing on the TR's steering rack?  There are so many splined connections on the steering gear shaft, that will come into effect once the rack is in the central position. 

So is it purely a matter of setting the steering joints an equal amount on either side, and setting the tracking to parallel or slightly toed in, and then setting all the other splines to get the steering wheel and indicator notch into the right place?

Is there is a simple may to determine the rack central position mechanically?

John

Yes Triumph did have a steering rack centring pin that screwed in the hole where the grease nipple goes.  It located in a pilot hole in the rack bar.  Not all rack bars seem to have that hole, so you are back to setting the lock with degree turntables under the front wheels.  I have posted a picture of it here previously.

 

I can go digging in the garage for it if you need sight.  It is a simple threaded thing with a spigot pin that locates in the top of the rack bar.

Cheers

Peter W

[Bfg]

1 hour ago, John L said:

Is there is a simple may to determine the rack central position mechanically?

John, assuming your car's toe in is approximately correct, and the track-rod-ends are the same on either side .. the simple way is to mark the thread where the track-rod-end is adjusted to (a junior hacksaw blade scratching into the thread groove is easy). Do this on both sides. Then undo them and count the total number of threads that were wound onto, on both sides.   You can try counting as you unwind them but I find it awkward to count on my fingers at the same time as unwinding each track-rod-end.   Anyway it's the total number of threads from both sides you're interested in.  Half of this number is how how many threads each track rod end needs to be wound on - for when the steering is central.

Pete 

[BlueTR3A-5EKT]

Triumph Steering Rack bar centraliser.

 

[John L]

Thank you Peter,  if I take out the large plug that holds the filler plug, and the bush and spring, I didnt think the sliding bush had a big enough hole to let that tool thru, so perhaps I don't have the dimple in the shaft to locate into,  I should be able to see the hole in the rack bar if there is one?

Just looking now at the sliding bush 12046 in parts it does seem to have a hole to suit the tool, so will see now if I have the dimple in the rack shaft.

John

Edited May 4, 2023 by John L

[BlueTR3A-5EKT]

1 hour ago, John L said:

Thank you Peter,  if I take out the large plug that holds the filler plug, and the bush and spring, I didnt think the sliding bush had a big enough hole to let that tool thru, so perhaps I don't have the dimple in the shaft to locate into,  I should be able to see the hole in the rack bar if there is one?

Just looking now at the sliding bush 12046 in parts it does seem to have a hole to suit the tool, so will see now if I have the dimple in the rack shaft.

John

The alignment pin is designed to fit in the lubrication hole and pass through the sliding bush and spring.   Many new racks that we sold in the 1970/80’s from Triumph included this alignment pin instead of the basic plug, which is how I ended up with this one.   I swapped it for a grease plug.   That plug does of course secure the rack electrical earthing cable.

[John L]

Further investigation, and thank you Peter, I do have the hole in the rack bar, so just need to do the job now.....

I still don't really understand why my right wheel would turn much more on a left turn, and scrub the gravel, than it does on a right turn.  the wheels are held by the steering rack, and if the tracking is correct why should it do this? 

The steering rack moves the wheels the same to the left as to the right,  not like a system with an idler box in between.

The lock stops are there and working, the large ones without the offset hole.

Or does this mean there is something else adrift that I'm missing?

I see now the steering rods do have different amounts of thread on each side, the right side has only about 2 threads showing at the steering joint, and much more on the left, the car drives straight without touching the steering wheel.

John

[Motorsport Mickey]

Sounds like the vertical link is bent on one side of the car.

Remove the vertical link strip and place the threaded end into a chuck (if on a lathe) or a large vertical drill or miller, grasping the bottom threaded end lightly without damaging the threads. Place a DTI (clock) in a drill chuck mounted in the tailstock, adjust the DTI needle to read inside the ball joint tapered hole at the top of the neck. Turn the chuck and measure how much the ball joint hole moves out of centre, within about 50 thou one side to the other is an expected amount. In use they do tend to pick up bumps from kerbs etc which imposes a bending load to them...and they bend. That then affects the amount of steering input that gets to that wheel...or not, I've checked 4 or 5 when racing before selecting a pair to use.

Here's a thread from the British Car Forum where CJ shows how to test them, it's how I've done it...but never made a point of taking photos of the process. CJ (John Durant) does a good job of measuring and selecting vertical links.

https:www.britishcarforums.com/community/threads/triumph-spindles.98354/

Mick Richards 

[stuart]

16 hours ago, Motorsport Mickey said:

Sounds like the vertical link is bent on one side of the car.

Remove the vertical link strip and place the threaded end into a chuck (if on a lathe) or a large vertical drill or miller, grasping the bottom threaded end lightly without damaging the threads. Place a DTI (clock) in a drill chuck mounted in the tailstock, adjust the DTI needle to read inside the ball joint tapered hole at the top of the neck. Turn the chuck and measure how much the ball joint hole moves out of centre, within about 50 thou one side to the other is an expected amount. In use they do tend to pick up bumps from kerbs etc which imposes a bending load to them...and they bend. That then affects the amount of steering input that gets to that wheel...or not, I've checked 4 or 5 when racing before selecting a pair to use.

Here's a thread from the British Car Forum where CJ shows how to test them, it's how I've done it...but never made a point of taking photos of the process. CJ (John Durant) does a good job of measuring and selecting vertical links.

https:www.britishcarforums.com/community/threads/triumph-spindles.98354/

Mick Richards 

Direct link here https://www.britishcarforum.com/community/threads/triumph-spindles.98354/

Stuart.

[Z320]

Hi John,

with your front wheels and steering wheel straight ahead,

how much turns of the steering wheel do you have to full right and to full left?

Ciao, Marco 

[John L]

Marco,  It seems to be very nearly the same both sides at not quite 1 and 3/4 turns.  Will this tell you something?

John

[Z320]

Yes,

everythink seems to be OK with your middle position.

The reason must be something else..... 

And the problem is only the right wheel on a max left turn?

The left wheel on a max right turn is inconspicuous?

Marco