Presumably either the control arm pivots on its end of the eccentric bolt, or the eccentric bolt pivots in the caster block.

I suppose it's possible neither pivots and the rotational deflection is all done in the rubber, but that's seems unlikely.

 

The lower control arm bushing is fixed in the control arm and pivots on the eccentric bolt which is fixed secured to the castor block. Otherwise the castor would consistently change, not good.

 

Oh oh, sounds like I'm missing a part. There's a bushing in the rear control arm hole?

 

T&T Racing, are you using early steel control arms? It sounds like they have bushing in the back, but the cast aluminium arms don't....

 

I always thought that it’s the two rubber parts of the bushes that twist. Isn’t that how all rubber isolated suspension works?

The outside of the bush isn’t moving as it’s fixed to the caster block at the rear and the control arm at the front. Then both the front bolt and the rear eccentric bolt are clamped and fixed to the inner rubber bush sleeve, and the sleeve is permanently bonded to the rubber bush.

Only movement available to provide a “pivot” is the bushing rubber twisting as the control arm goes up and down.

 

I'm beginning to think this is indeed the case. Otherwise there would need to be some bronze, oilite, or something in there to prevent galling (at least on the steel-to-aluminium one).

The last suspensions I did were either Heim joints or delrin bushings with a "distance piece" in the middle (the distance piece is clamped and the delrin pivots on it). But that doesn't necessarily mean rubber suspensions are the same....

This would suggest that it would be important to torque it all down with weight on the suspension (to get the correct centre point).

 

You should always do the final torque on any suspension components with the weight on the wheels regardless. How I was taught anyway.

 

Continuing on with my control arm rebuild, I can't count myself much of a fan of the OEM ear-less internal retaining rings for the ball joints (nor of Rennbay's "drill a hole behind them" method of extraction). I persevered with a small screwdriver. (Compressing the ball joint spring makes this a bit easier, but it's still a royal PITA.)

My plan was to replace the multi-layer spiral rings in the Rennbay rebuild kit with some standard "eared" retaining rings. Only Rennbay's design of the bottom plate has changed recently -- it now has a lip which will interfere with the ears. (In fairness the lip probably does insure their multi-layer spiral rings are fully seated. But those rings feel too flimsy for my tastes.)

A few minutes on the lathe sorted that out.

Rennbay bottom plate on the left, an example eared retaining ring in the centre (slightly too small for this job), lathe-adjusted plate on the right.

 

Looks like a good alternative but I would run it by Travis and see if there was a specific reason he didn’t use a regular snap ring instead of the spiral.

Also don’t forget to epoxy that ring in place otherwise it will come out. Amhik

 

A spiral ring is generally used where a rotating part might snag and unseat an internal snap ring but spiral is a better choice for most applications anyway.

And yes, the range of motion of the caster block is rubber only unless you upgrade to spherical.

 

...or if you use poly. The poly need lubrication as they rotate instead of twisting like rubber, so they do provide more range of motion. However once the rain has washed that grease away those fu#ckers squeak like a scared piglet.

 

Sidepipes are the solution to squeaky poly bushes:

 

@jeyjey

Or a couple hundred watts and this -

 

As I wait for the right size internal retaining ring to arrive I thought I'd get started on the salvage struts I picked up for conversion to Bilsteins.

Got the first spring compressed and then tried to undo the top nut. Oh yeah, this is where irina25661 used a deep socket with a "window" cut in it (for the Allen key).

Not wanting to undo it a 1/4 turn at a time like he had to, I decided to go the opposite way and use a combination wrench on the outside of a 22mm socket, with the Allen key coming through the normal 1/2" drive hole.

I don't have a dividing head and the socket was just too big to fit in a 5C collet, so out came the rotary table. (Damn that thing's heavy.)



Should do the trick:

 

Nice job!