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Front suspension--asking the experts here

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drooartz

drooartz

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I can't see the vids from here, but if there's any more than a very tiny amount of movement, they need rebuilding.

I'm not allowed to put the precise description of how much slop is reasonable because apparently someone might be offended by a word with *s in it, but the expression starts "3 tenths of" and ends with "all".

In any case, once you've got it stripped down that far it's hardly worth putting it back together in order to take it all apart again in a year or 2.
 
Hah, is telling you they worn out Drew. They are a bit awful, should be no slop at all.
 
That's what I figured, but I thought I'd ask. Guess I'll be putting in a few calls and orders in the next week or so.
 
The question is... Do the threaded inserts need to be replaced? Looks suspicious.

Oh, and have you tried to remove the fulcrum pin yet? It may be seized to the KingPin.
 
I haven't. I got as far as getting the steering arms and shocks off. I'll have some more time this weekend to try to tackle the rest of the disassembly.
 
There is someone around that rebuilds A arms much cheeper than new.

Although I think I would test fit new Fulcurm pins before I went that root. Just might have to cut the old pins out of the A frame. They seem to grow in there. However if you are going to use new swivel pins and bushings not a big deal.
 
Drew

I know apple sells rebuilt ones, although they have mixed opinions in this enviornment.

Pat
 
Definitely look worn and loose to me on the video. Since it's a big deal (at least to me) to tear it all down, I would recondition it all. I think you'll be much happier with the ride and stability.
 
That Jethro Tull in the second clip?
 
Nope, something from the local jazz station -- it was on in my garage while I was working.
 
Drew,

If you decide you need rebuilt a-arms, I know some one who does it. PM me and I will send you his number. He does not have a website.
 
Unfortunately some of TimD's photos have gone, so I don't know what his solution was.

I've never been convinced that the threaded fulcum pin was a good design, and when I rebuilt the A40 suspension I replaced the threaded pin with 5/8" (I think it was) silver steel, had some phosi bronze bushes turned up (including grease nipples) to replace the threaded inserts.

My logic, apart from cost, was to give a better surface area to take the load and make it easier to dismantle next time - at least you can hit it with a big hammer to drive it out whoops, sorry <workshop manual speak> "apply gentle pressure with a suitable press" </workshop manual speak> if it seizes in the king pin.

Unfortunately I had to sell the car after a year, so never found out if it lasted longer than the original.

I also know someone who used a bolt straight through, but I don't know how well that lasted either.
 
drooartz said:
Nope, something from the local jazz station -- it was on in my garage while I was working.
Click to expand...

"How to jiggle your "A" frame" by Herbie Mann methinks!! /bcforum/images/%%GRAEMLIN_URL%%/jester.gif
 
True, more surface area, but the same vertical bearing area. Normal forces times cosine to angle of threads (60deg) gives only the area as viewed from above. Threaded bushing surfaces do give a large axial thrust surface, but that is not necessary for the trunion bushings. In other words, the 5/8 bolt (if hard enough) provides at least as good bushing surface as the threaded system and is a lot easier to install and maintain.
 
So Donn, If you had to guess, why did the Austin Engineers make the fulcrum threaded?
 
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