Steering Rack Puzzle

[david.g.chapman]

It is time for me to have a look at the steering rack on my +2.

I know there is significant vertical play at both ends of the rack when each track rod is gripped and moved up and down. On the pinion side it feels tight until more force is applied - then there is a lot of movement, about 2 mm it seems. It feels as if the pinion and rack teeth are sliding against each other.

I know there is no bushing fitted on this side, but I do not know how the rack itself is constrained here, not having seen the rack dismantled before. Does the steering rack body retain the rack itself and stop this play?

I have no problem with the other side as I managed to get a replacement rack bush from Sue Miller at Stoneleigh. Replacing this should be easy (he says)!

Dave Chapman.

[ppnelan]

Dave,

The pinion itself 'restrains' vertical movement of the rack at this end - a design feature frequently criticised in the past on this forum. I suppose either the pinion &/or rack teeth are heavily worn, or perhaps the pinion bearings are shot? Do you get the same 'slack' at this end with the steering in positions other than straight ahead?

I would have thought it best to get a recon one if the pinion end is loose.

Matthew

[david.g.chapman]

You could be right, a recon rack may be required. What I dont understand is - what is worn out to give this movement? There is no play in the pinion and rack teeth, as there is no lost motion in the steering. There is just this strange vertical sliding about, with no bush to retain the rack.

I will just have to take the rack apart and have a good look at the way the pinion engages with the rack... I could not find anything in the past forums on this specific point, so will let you all know what I find when I do it.

Dave Chapman.

[RotoFlexible]

I'm a little reluctant to post on this because I am not sure of my facts, but there is a spring-loaded saddle piece that holds the rack securely against the pinion. The saddle bears on the smooth (non-toothed) side of the rack and is partly responsible for preventing the motion you seem to be experiencing. I don't recall if that spring load is adjustable, and my manual is at home.

Hope this helps.

[david.g.chapman]

That could be it.

I was confused by my Brooklands Books manual that shows a drawing of the rack (Fig 9:7). For "clarity" the rack itself is shown upside down with respect to the rest of the assembly, probably to show the teeth. The saddle is shown in the right orientation to engage the pinion shaft, just to add to the confusion. Fig 9:6 is better, athough it does not show the saddle at all.

I did not realise that the rack teeth are on the bottom, with the pinion below the rack. How's that for a senior moment! Still, I am old enough. Looking at the rack itself shows the true situation, with the spring loaded plunger forcing the RACK against the PINION, while stopping the sideways movement. I must have a worn saddle or a weak preload setting. Or have I still got it wrong?

Thanks again,

Dave Chapman.