Control Arms
Removing the control arms is a simple process. The ball joints on the control arms are not serviceable like normal ball joints, and the ball joints are notorious for going bad. This document will cover removing the control arms, as well as rebuilding the ball joint in the control arm.
Control Arm Removal
First remove the sway bar where it attaches to the control arms using the separate write up on that subject.
Note that the control arms have a bushing with an eccentric bolt. This is used to set your alignment of the wheels. Here is a diagram from the Porsche parts catalogue that should help explain this. Note that the ball joint itself is not a separate part; hence the lengthy rebuild with aftermarket parts.
In order to not mess with the alignment, we'll just remove the entire bushing assembly with the bolt. Do this by removing these two bolts that hold the bushing support.
Remove the front control arm bolt.
Remove the bolt that holds the ball joint onto the knuckle.
Use a brass hammer, a dead blow hammer, or a regular hammer with a brass push; and knock the control arm loose. Inspect the ball joint and bushings for possible replacement.
Ball Joint Rebuild
Here is the ball joint kit that I received from www.944online.com. This kit is the track/performance kit which includes bronze bushings. I would recommend that anyone install this kit instead of the cheaper kit without the bronze bushings. If you're going to go through the trouble of taking your control arms apart, you might as well install the best parts possible.
Here you can see the ball joint. Needless to say, it is pretty trashed. It was extremely loose inside the control arm. The boot is torn, which indicates that the internals have not seen any grease in quite some time.
The bottom plate of the ball joint has a coat of epoxy over it. This is just a moisture barrier. You'll need to scrape this off to get access to the circlip that holds the ball joint bottom plate on. Use a small chisel or flat head screw driver to remove as much of it as possible.
The circlip that holds the ball joint together should now be accessible. Make sure there is no more epoxy around that circlip, or it might not come out. If you can get the circlip out, remove it. If you can't get the circlip out, or don't even want to attempt to, use the following optional steps.
OPTIONAL STEP 1
I couldn't get the circlip out of the control arm, so I took a further step. I used a dremel to cut a small notch between the two circlip ends. After the notch was cut, I rotated the circlip around a bit to where the end of the circlip was in front of the notch.
OPTIONAL STEP 2
I was able to get my smallest flat head screwdriver behind the circlip. Push against the circlip, and the end of it should pop out.
Work the circlip out of the groove by working it around in a circle until it finally pops completely out. Save the circlips! The ball joint kit comes with new spiral retaining rings, which I am not fond of.
When the circlip pops out, the ball joint assembly should be able to pull out easily. You'll soon see the condition of your ball joints. Most likely, your 20+ year old ball joints will look just as terrible as mine.
Take the pieces out of your 944 Online ball joint kit. Get a feel for what each piece is. Here is how they will be assembled inside the control arm.
Insert the upper bronze bushing inside the control arm in the following orientation. The smaller diameter side should be inserted into the control arm first.
You should be able to push the upper bronze bushing all the way down with your hands. If it won't go all the way down, don't worry. It will compress down later on whenever you compress the ball joint assembly with the C clamp.
Coat the new ball joint with the grease, and drop it behind the brass bushing.
Drop the lower bushing in next with the pointy side facing up.
Drop the O-ring in place. Make sure it sits on the lip inside the control arm.
Drop the spring in place with the pointy side facing up.
Put the retaining plate on top of everything. Try to get it as level and centered as possible. We'll be compressing everything down.
Place a large socket on the bottom side of the control arm. The ball joint needs to fit inside the socket. I used a deep 22mm. Tighten a C clamp with the other end on the retaining plate.
Compress the C clamp until the retaining plate is underneath the circlip ring. If the bearing plate is not low enough, the circlip won't go back in.
Feed in one side of the old circlips and begin working it around inside the groove. The notch you cut earlier with the dremel will help with this.
When the circlip is in place, remove the C clamp and install the grease zerk with cap. Don't forget to rotate the circlip so the ends are far away from the notch (unlike in this picture).
To install the boots, you will have to turn them inside out. The boot on the left is how they should come in the package. The one on the right is turned inside out.
Use your finger and apply grease to the areas that the boot will cover.
Place the boot turned inside out over the ball joint (right control arm). Push it down as far as it will go. Then flip the boot over and it should pop down over the lip of the control arm (control arm on left)
Open up the epoxy and mix a small amount inside each control arm. Be careful not to put so much in as it will go up to the grease zerk. Let epoxy dry.
