Steering shaft movement

[jordway]

My Caterham is a 2004 SV Roadsport.  I remove the Momo every time I get in and out.  I've had the car 2.5 years and put 3K+ miles on it since then.  I've gotten into the habit of giving the steering wheel a pretty good jerk when I put it on, to make sure it's seated.  A couple days ago, I did this and the post pulled out maybe a half inch or so.  The car was parked, of course.  I pushed it back in.  It feels secure and only pulls out if I jerk it pretty hard (which, of course, I will stop doing!).

 

I've driven it a couple times since then, and it steers fine and it keeps a straight line if I let go of the wheel on a level straight stretch.  The only thing I notice is that there now seems to be more play in the steering.  Granted, this could be totally in my head following a bit of an "Oh crap!" moment.  Now, there is maybe about a 15 degree give in the steering wheel before the wheels respond.  I don't recall that being the case before this happened.  Other than that, it seems to steer normally on 90 degree turns.

 

Should I be worried?  What all should I be checking?  Perhaps a bit of guidance from @slngsht to find the lock screw mentioned in the Sep 7, 2007 post below or any insights from @lowflyer regarding the Sep 10, 2007 street rod story might point me in the right direction.

 

Thanks again for any feedback!

Edited July 22 by JohnCh
Split thread and moved to tech forum

[CarlB]

I do not have a Caterham removable wheel hub, but you need to be very careful. It sounds as if the hub might be coming loose from the steering shaft. The first thing I would do is hold the steering shaft in the engine compartment to keep it from moving. There are three pieces that make up the steering shaft. The hub your steering wheel bolts to. A tube that connects the hub to the solid shaft that connects to the steering rack. Hold the shaft from turning and see if there is any play. Vice grips will hold the steering shaft. The only thing that would be simple to fix would be the clamp between the tube and the shaft. Look under the brake master cylinder at where the steering shaft come through the fire wall. There is a clamp that holds the tube to the shaft. If the tube is turning and the shaft isn't, make sure the clamp is tight. If the hub is moving and the tube isn't, I do not know how that hub attaches, but I would suggest that if you do not have a lot of experience working on cars have a mechanic look at it. Steering can fail catastrophically.  You should also check the joint at the connection to the steering rack, but this would not cause the wheel to move in and out. The last thing would be if the wheel was loose, or the removable wheel hub is broken. If nothing is loose in the tube and shaft it could be the connection where the hub comes together. 

[jbcollier]

Check the steering shaft slip joint.

[theDreamer]

Interesting happenstance, I was going through the three Assembly Guide binders that came with my car and I found this technical piece penned by Jez Coates. Among other questions it seems the original owner of my car had a similar issue with what was described as steering slip.

Jez' first comment was to check that the grub screw in the steering clamp was tight. (see attached image)

[jordway]

Reporting back on this topic...  Many thanks to @CarlB, @jbcollier and @theDreamer for the feedback and to @JohnCh for the helpful build link.  Indeed, the issue was the clamp connecting the upper and lower columns.  The securing bolts were still tight enough to turn the column and wheels, but loose enough to cause the play I was feeling.  They were loose enough that it took some time alternating between the two to get them to 14 Nm.  I made sure the grub screw and securing bolt were also tight.  This totally resolved the play and it's back to the feel I'm used to after test driving.  I was surprised that the two securing bolts don't have nuts (although there is not much thread coming out of the clamp to put a nut on anyway).  I checked the assembly manual and photos, and this is as it should be.  Someone outside this forum suggested that I disassemble it and use blue loctite on the entire length of the securing bolts.  I'm not sure that's a good idea for a clamp that might need regular tweaking.  Alternatively, I considered getting two longer blots and use nuts.  But, I sure don't want to end up with a cross threading issue.  I plan to just keep a close eye on it, and if it gets loose again in a short amount of time, I'll consider how to make it more stable.  Anyone here had an issue with that clamp frequently getting loose?  Of course, correcting my bad habits of yanking on the steering wheel will likely help!

 

To be safe, I got under it and checked the entire steering mechanism using the assembly manual and torque tables as a guide.  Splines are all good.  The only other thing I found was that the rack clamps needed to be torqued ever so slightly.  So slightly that I really doubt that was causing any steering issue, but they are to spec now.

 

Thank you very much!    

 

 

[anduril3019]

Is that the before or after shot?

 

Just asking because typically you want to back the grub screw all the way out, and then the two parts of the clamp will tighten without a gap between them. Contact, or near contact, with the flat of the shaft is what keeps it from rotating. The grub screw is then tightened, and it's main job is to keep the shaft from sliding in and out, except in an accident.

 

Again, that's just the typical fit, yours could be different. 

[CarlB]

3 minutes ago, anduril3019 said:

Is that the before or after shot?

 

Just asking because typically you want to back the grub screw all the way out, and then the two parts of the clamp will tighten without a gap between them. Contact, or near contact, with the flat of the shaft is what keeps it from rotating. The grub screw is then tightened, and it's main job is to keep the shaft from sliding in and out, except in an accident.

 

Again, that's just the typical fit, yours could be different. 

If this is a after shot, anduril is correct. The silver part of the clamp should fit against the shaft.

[jordway]

1 hour ago, anduril3019 said:

Is that the before or after shot?

 

Just asking because typically you want to back the grub screw all the way out, and then the two parts of the clamp will tighten without a gap between them. Contact, or near contact, with the flat of the shaft is what keeps it from rotating. The grub screw is then tightened, and it's main job is to keep the shaft from sliding in and out, except in an accident.

 

Again, that's just the typical fit, yours could be different. 

Good question.  That's the before photo.  Here's the after, although not the best angle for your point.  But, if you zoom in you can see that the two halves of the clamp now meet.  The before photo was intended to show how loose it was.  I loosened the grub screw/nut first, then torgued the clamp, then retightened the grub screw/nut.  Let me know if you see anything suspicious in the after photo.  Happy to take better ones.  Thanks for your feedback.

[anduril3019]

That looks better!

[CarlB]

That should work fine