Needed to replace the ball joints on my W201 and I didn't have the required spring compressor to remove the arm and use a shop press to r&r nor the special MB BJ press. This method worked without removing the arm from the car so I didn't have to compress the spring. Side one took about 2 hours, side 2 around 30 minutes.

Removal was caveman. Set car on jackstands. Removed wheel. Jacked arm up to compress spring with floor jack against the rotor. Lowered the arm down on a large wooden block where the edge of the BJ just dug out a bit of the wood. Unbolted strut (top end also) and BJ then tied the hub aside. Several hard hits with a sledge hammer knocked it out. Heated the arm end a bit to loosen things up some before hammering. I suspect you don't want to get that metal too hot as it appears to be hardened.

To reinstall, I dug through the collection of pipe fittings and found a galvanized pipe junction that fit the BJ bottom perimeter and was slightly larger than the hole in the arm. Welded about a 3" section of pipe on the top half and a flat piece of metal on both. Cleaned the opening really well with a wire brush attachment on a drill. Lined up the BJ, put the jig on the bottom with the wooden block under it. Used the jig on the top to hammer the arm down onto the BJ. 4 or 5 smacks with a 1 lb hammer seated them. The BJ isn't 90 degrees off the floor so the bottom jig has to be wedged a bit to fit firmly around the hole perimeter. The jig could be cut off at the correct angle before welding on the flat metal.

Caution - make sure the car is securely supported (your hitting it with a sledge hammer) and the wood is at least a 6" x 6", larger if available. If your wood is knocked out from under the arm with the strut unbolted the spring can be dislodged with great force, potentially causing a serious injury. You might consider chaining the spring in there for added safety.

If the rubber bushings are bad on your A-arm (fortunately mine look solid) then I couldn't figure a way around the spring compressor which is a specialty tool to MB's and priced accordingly.

Hope this helps somebody.

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You can't always get what you want, but if you try sometime you just might find you get what you need.

You don't need a spring compressor for this job. Just put a jack under the lower control arm. Support the body with a jackstand.

Here's a novel method done on a W124 - same as a W201
Snapped wishbone ball joint - Page 5 - Mercedes-Benz Owners' Forums

The proper tool is only around $150.00. You don't need to compress the spring.

Didn't mean to infer the spring had to be compressed if one had the proper tool. What I was attempting to say was since I didn't have access to the proper tool, I wanted to use the 12 ton shop press to push the BJ's in and out. To do so, I would have to remove the arm from the car. This would require removing the spring (unless I'm completly missing something)

To me a $150 tool is only for someone who plans to repeatedly perform a repair, not a DIYer on his own car. no return on that investment. Just my opinion.

__________________
You can't always get what you want, but if you try sometime you just might find you get what you need.