Steering rack

Author
Discussion

sdio

Original Poster:

287 posts

130 months

Monday 15th May 2017
quotequote all
I have a small issue with my steering rack and would need your advice.

The steering rack has no play at all, from steering input to the wheels the slightest move is transferred with no slack.
However there is a "clonk" quite often when initiating the turn to the right and i can see the little spline sticking out of the rack where connected to the UJ is having a small play in and out but also to the side when the clonk is heard.
To me it is clear there is some slack there.

By lifting the front wheels of the ground i tried to tighten the preload by the 36mm bolt and allen key.
By tightening the allen nut by about 20degrees the steering is slightly heavier (with the wheels off the ground) but now i notice that when turning the wheel from full left to full right i can feel at some places it lightens up a little bit. Something which cannot be felt it the preload is set up properly.

As expected the "Clonk" noise only happens when the wheels are on the ground and there is some resistance.
Obviously i need a new rack, after contacting Titan they offer no service and no parts to caterham racks so i have only the option of replacement frown

1. Are you aware of a place i can source a repair kit?
2. Is it dangerous to drive the car as is?

Cheers

sdio

Original Poster:

287 posts

130 months

Tuesday 16th May 2017
quotequote all
boy said:
The Titan racks are a Caterham only part, they wont deal with you direct or recon them.
Correct so the options are either buy new now or postpone until the funds allow.
Would you say it is still safe to drive the car?

sdio

Original Poster:

287 posts

130 months

Tuesday 16th May 2017
quotequote all
boy said:
sdio said:
Correct so the options are either buy new now or postpone until the funds allow.
Would you say it is still safe to drive the car?
With all respect that's your decision....
Absolutely and no offence taken.
The question was with the intension of getting other people experience of similar description or a better understanding of the mechanical issues in hand.
😊

analog_me

Original Poster:

287 posts

130 months

Friday 19th May 2017
quotequote all
sdio said:
I have a small issue with my steering rack and would need your advice.

The steering rack has no play at all, from steering input to the wheels the slightest move is transferred with no slack.
However there is a "clonk" quite often when initiating the turn to the right and i can see the little spline sticking out of the rack where connected to the UJ is having a small play in and out but also to the side when the clonk is heard.
To me it is clear there is some slack there.

By lifting the front wheels of the ground i tried to tighten the preload by the 36mm bolt and allen key.
By tightening the allen nut by about 20degrees the steering is slightly heavier (with the wheels off the ground) but now i notice that when turning the wheel from full left to full right i can feel at some places it lightens up a little bit. Something which cannot be felt it the preload is set up properly.

As expected the "Clonk" noise only happens when the wheels are on the ground and there is some resistance.
Obviously i need a new rack, after contacting Titan they offer no service and no parts to caterham racks so i have only the option of replacement frown

1. Are you aware of a place i can source a repair kit?
2. Is it dangerous to drive the car as is?

Cheers
Hi all,

As more information is now available I would like to consult your wisdom for further feedback.

As mentioned the "clonking" noise when turning to right can be reduced but not remediated by tightening the preload nut a tiny bit.
I removed the nut of the preload bolt and tried to take out the nylon thrust pad shoe with no success.
I then realised the rod end of the rack on the side where the steering column attached to it is having a huge play. See below

https://www.youtube.com/watch?v=AAVTrUKYBN4

https://www.youtube.com/watch?v=0dGFfQaZGww

https://www.youtube.com/watch?v=XiZiIkDS73Y

After further checking and comparing with the opposite side it seems the bush number 7 from titan is installed from the other side but is missing from the side being closer to the steering column.

This is the drawing for an elise steering rack which i do not know to what extend this might be similar

http://www.titan.uk.net/_/uploads/casestudies/67/l...

Is this normal for a caterham rack?
All the slack is now taken by the preload nut!
Is this how it should be?
This is where the "clonking" noise is coming from, there is no slack nowhere else.
Thanks

sdio

Original Poster:

287 posts

130 months

Saturday 20th May 2017
quotequote all
Thank you david
That explains the alignment markings on the spline and the new track rod ends in combination with it's secret race life...

analog_me

Original Poster:

287 posts

130 months

Monday 22nd May 2017
quotequote all
Hi all,

I took a couple of videos which really summarize the lot.
Both videos where taken with the wheels on the ground as i was turning the steering wheel to the right.
One can clearly see the spline moving in and out when the "clonk" sound is heard. The pretension nut is now properly adjusted.

https://www.youtube.com/watch?v=bu0bts8Llp8

https://www.youtube.com/watch?v=T8TWlu1uM0k

The in and out movement is of the order of 0.3mm as measured with a filler gauge higher up on the steering column where passing through the dashboard.

What can be done at this stage ?
If i put a circlip to keep the spline in place would that be any better?

Cheers
Vagelis



analog_me

Original Poster:

287 posts

130 months

Tuesday 23rd May 2017
quotequote all
Hi,

Ok, Ok i am convinced and will have to bite the bullet and buy a new one.

What is the disadvantage of replacing my current rack which is a 22% with a 8%
Caterham was telling me on the phone that they do not encourage people to install the 22% for road use but only for track use.
The disadvantage they mentioned in that the effect of bumpsteer on the wheel is more pronounced with the 22%, however my car feels like having no such effect...
I was thinking that wear as a result of parking will be more on the 22% thus not recommended this for road use ???

On the road the 22% is not too quick, in my opinion it feels just right but really i havent tried another caterham to compare it with.
The 22% is about GBP368 vs 312 for the 8% but the main disadvantage is the 22% has nearly 1.5 month of waiting time vs on stock for the 8%!

What are your thoughts and opinion?
Which one should i order?

Thanks