Steering rack problem

[nickk]

I’ll check my bar stock tomorrow and report back.

 

[Morris]

I’ll check my bar stock tomorrow and report back.

If you don't have anything suitable I have some en24 here. It's Hex bar but I could rip a bit down to size and post to you.

 

[bricol]

I'm not sure th theory of hardened smooth surface will prevent the aluminium picking up - we use ceramic tooling to form aluminium - very tightly controlled tolerances, finishes etc - and it will stick pick up horrendously if lubrication isn't sufficient.

 

[Seadog]

In the case of a steering rack the parts aren't going to be moving at supersonic speeds, I woukd hope.

 

[8ob]

Lengthen the slot, machine it parallel, then make a rectangular spacer giving more contact area. It may make the steering slightly heavier, though.

Not sure about lengthening the slot but the rectangle idea would be worth a go, could even be the one piece with two holes doing the job of both spacers.

Bob

 

[jmp49]

If you square off the edges of the slot instead you will have created a stress raiser at the corners which might cause it to crack.

 

[Mick Annick]

Not sure about lengthening the slot but the rectangle idea would be worth a go, could even be the one piece with two holes doing the job of both spacers.

Bob

I did think that might be a good idea - this rack was definitely made down to a price.

 

[indykid]

I'd want to machine the slot back parallel and central on the tube to make sure everything is square and engages fully (I expect one face of the slot to be more worn than the other depending on the angle of the track rods), then as above, machine a long block to span both bolts, with radiused ends to allow full travel.

You might consider some delrin inserts in the top and bottom face of the block sat 0.25mm proud. You'd then have a serviceable wear face that even if it wore out completely, would then engage with the surrounding steel, still leaving you with a better situation than current. Whatever material you used though, you'd be moving from line contact on two bushes to face contact that's probably approaching a fifty to hundred fold reduction in contact stress so the wear should become insignificant.

How many kms a year do you do and how many kms has your rack survived so far?

 

[500e]

Your car must be 1986 ish or y
ou would have a Burman box
Think 84 was first time JK rack offered and was optional.
Don't remember problems with them, the Burman boxes are now sought after spares and command a premium.
Did a fair bit of work for Andy at Four Elms Morgan and built ran the hill climbed car for him

 

[Mick Annick]

Your car must be 1986 ish or y
ou would have a Burman box
Think 84 was first time JK rack offered and was optional.
Don't remember problems with them, the Burman boxes are now sought after spares and command a premium.
Did a fair bit of work for Andy at Four Elms Morgan and built ran the hill climbed car for him

Mine’s a 2000 +8 3.9 14CUX, well into the Jack Knight era before it all went wrong and Quaife stepped in. Apparently the Quaife rack is an almost exact copy of the Knight one and are interchangeable, I’m following up a lead on a used one at the moment to keep as a spare, though with a new set of spacers the current one will outlive me. It’s done 65k miles, there’s no directional play just this bit of up/down play which the tester picked up.

I’m booked in with Mulfab for the king pins and bushes, it’s under new(ish) ownership - before he retired Pete Mulberry supplied the stuff on the car at present when he shared a workshop with Chas Windridge who fitted it all for me. Since retiring I’ve done most of the work on it myself, though for most of it’s life it was serviced by Mike and Ben Duncan - the Morgan world is blessed with some decent people.

Andy’s a nice guy, met him a few times and bought a set of AVO’s off him a couple of years back.

 

[Mick Annick]

I ordered a new gaiter for the rack from a guy in Germany, the original style is still available but is very inflexible, the new one is in three parts - ali centre tube with a replaceable gaiter either end. I didn’t realise when ordering it comes with new spacers as the profile is different to fit the tube, so that’s saved @nickk machining me up some new ones which he’d kindly offered to do.

 

[Other Daniel]

I ordered a new gaiter for the rack from a guy in Germany, the original style is still available but is very inflexible, the new one is in three parts - ali centre tube with a replaceable gaiter either end. I didn’t realise when ordering it comes with new spacers as the profile is different to fit the tube, so that’s saved @nickk machining me up some new ones which he’d kindly offered to do.

I'm also happy to machine up some, if you wish.
I was thinking to do them in bronze.
But, if you're sorted, then no need. Offer's there if
you want it though....

 

[Mick Annick]

I'm also happy to machine up some, if you wish.
I was thinking to do them in bronze.
But, if you're sorted, then no need. Offer's there if
you want it though....

Thanks Daniel, the kit looks quite good, and the spacers supplied with it are quite snug in the rack so fingers crossed it’s all OK when I put it all back together.