Control Arm bushing replacement

[ewalt98]

My 85.5 944 front end has the 60mph shimmy coming from the passenger side, so I started to diagnose and repair it last year.
I found the inner wheel bearings were shot, along with the struts and sway bar bushings on that side. These were all replaced, with Bilstein struts from a later car and parts from Pelican, and I then had the car aligned by a Porsche shop. I also added front strut bar braces. All this helped the ride, but the shimmy is still there.
Oh, the ball joint feels tight on each arm.
This weekend, I started on replacing the rear control arm bushings with the OEM parts from Pelican, and ran into a couple of snags:

1. The passenger's side inboard nut holding the bushing (castor block) came loose as I was removing the bushing. I 'think' the bolt was tight, though. After removal, I found that the bolt had completely broken away from the frame. I also noticed that there were chucks of rubber missing from the bushing, so there has been a lot of movement in that area.
2. After installing the driver's side, then the passenger's side bushing, I noticed that there are two different sized washers (#12 in pic) for each bolt holding the bushing. Each side of the car has a washer that is both thicker and larger in diameter than the other, and I'm not sure which bolt, inboard or outboard, they were on.
3. The original bushings have a small bump on it (near the end of the pointer line for #10 in the pic) that allows centering of the bushing to the frame, the new one does not. Now, I know my toe will be way off.

So, my questions are; I was able using a magnet and small screw driver to get the bolt started on the loose nut, then tighten it down to spec, but is that good enough, has this happened to others, and if so, how do you fix it since you cannot get to the nut without cutting into the frame?? Also, what is with the different washers, do they have to be mounted specifically in-board or out-board? The larger washer seems like it could position the bushing a bit when tightened.

Any thoughts would be greatly appreciated!

Eric



1985.5 N/A 944

[kdjones2000]

Sounds like the nut inside the car itself has become free, possibly due to the excessive vibration you have been experiencing. Good job on still being able to put things back together

The only way to properly fix the nut is to cut the boxed part of the frame out and re-weld a nut, then weld things back together. There have been several threads here or on the "other forum" detailing out this procedure.

Since you were able to tighten the bolt down to spec I think that you should be fine as it is.

Regarding the washers holding the caster blocks, mine are the same washers on all bolts. You may have some replacements on your car, hard to tell.

Replacing the caster blocks with the 968 ones requires a front end alignment anyway, as the height of the rear of the control arm off the frame is changed. Not a lot, but best to have it done correctly.

Good luck, Keith