More LCA - Hotchkis problem ?

Pete · Post by **Pete** » Thu May 30, 13 11:09 am

In terms of Root cause - either the Pins are too long (incorrect part), or (more likely) the Inner or outer Bush shells have creased and are preventing either the outer bush shell fully entering the LCA, or preventing the pin fully entering the inner bush.

I have done loads of these, and still managed to crush one of the shells using a 10 ton press when it went off-centre

Pete · Post by **Pete** » Thu May 30, 13 11:10 am

..and I agree with Ade that IF you are going to re-use the Inner and Outer and stick Poly in it, the only way is really to burn the old bush out.

Mind you, if you are changing the pin too then you are on a bit of a hiding to nothing...........

Ivor · Post by **Ivor** » Thu May 30, 13 11:10 am

I have to agree Pete, I would always recommend stock bushes on the front for a street car, though I've had no problem with poly bushes on the rear springs.

Pete · Post by **Pete** » Thu May 30, 13 11:15 am

Poly on the Rear - and on the UCA's - is great!!!

That is how the Bee is set up.

Ivor · Post by **Ivor** » Thu May 30, 13 11:16 am

Fairy nuff! I'll make a mental note of that!

Adrian Worman · Post by **Adrian Worman** » Thu May 30, 13 11:30 am

morgan wrote:
Not sure what stops your LCAs moving forward though ? Must be the shaft butts right up to the torsion bar

The lca is positively located for fore and aft by the strut rod that attaches to the front of the K member, but you're right tho mate, the t bar does go some way in helping to stop it moving, having said that Ii never had a poly bush fail, squeak, move, whatever, .................... still recommend top quality polygrahite components if you're using aftermarket hi perf suspension components

Dave-R · Post by **Dave-R** » Thu May 30, 13 11:32 am

The diaginal LCA strut is what controls the LCA movement no matter what type of bush you use.

Dave-R · Post by **Dave-R** » Thu May 30, 13 11:36 am

You just got in before me there Ade.

The key to controling the LCA is the bush for the strut rod. Using a poly bush is essensial there. Some would say an adjustable strut rod is even better at the job. Because you can load the LCA forwards which not only stop the LCA from slipping back, but also adds a bit of positive caster.

Pete · Post by **Pete** » Thu May 30, 13 11:52 am

Agreed on the Strut rod bushing - Poly every time - or the after-market ones based on Heim joints, like "Bondo Bob" makes!!!

DaveBishop · Post by **DaveBishop** » Thu May 30, 13 12:06 pm

Hi Pete
TrevD made some adjustable strut rod for me

Pete · Post by **Pete** » Thu May 30, 13 12:18 pm

I KNEW you would bite, Dave

We need to see pictures!!!

DaveBishop · Post by **DaveBishop** » Thu May 30, 13 12:55 pm

Hi Pete I will try and post some tonight

morgan · Post by **morgan** » Thu May 30, 13 10:09 pm

This gets odder and odder.
Closer investigation shows that the shell for the bush (poly come in 2 bits) does NOT seat to the base of the LCA. There is a 3mm or so gap. (as can sort of be seen in pic A). This accounts for some of it.
However, pic B) shows the top of the shell - and its flush pretty much (maye 1mm in it). Can only conclude that either a) The shell doesn't go to the base or b) the shell edge has been flattened by the press and shouldn't be flat topped like that, should be just in the LCA.

But check pic C). Oddest of all. Pic looks out of alignment, on the bench they were not. Number of things to see -
1) Hotchkis pivot shorter by 3or 4mm.
2) poly bush is WAY longer than the pivot, and also longer than old. Assuming old was flush to torsion bar (or close enough) then there is no way that poly bush (at current length) would seat the pivot at the same point. Show as the diff between a) and c) in diagram.

This is really odd. I can get the length right by cutting off the muffin-top (or trimming it down) allowing pivot to seat further into the uca - but I shouldn't have to. It should be the right length???

Shells out, shopping basket open, start over I reckon at this stage.

morgan · Post by **morgan** » Fri May 31, 13 10:17 pm

Update -

Sorted. Brutal surgery, but alignment now good and all tight.
Long story short, had to shave ~1mm from the bottom of the bush, 5mm off the top allowing the pivot to seat to the same level as the original.
Bush is still contained all the way down, neck still rests on the top of the sleeve.

All now fits. Diagonal strut tight on new bushes. Torsion bars properly seated (complete with safety clip at tail end). Geometry looks like it should.
Still don't know why so odd - but hey, all good now.

Special nod to Pete - your pictures were more useful than you know - once I understood what needed to rest on what and which bits didn't matter as force held them anyway I was good. Anyway, in what I hope to be the conclusion of this, and just so the archive record is complete for future bodgers, here is the proof in pudding.

Thankyouverymuch. uh-huh-huh...

Pete · Post by **Pete** » Sat Jun 01, 13 12:44 am

Glad you have got it sorted, best keep an eye on things when you have got a few miles on it!!