Suspension #1: Front lower wishbone and ball joint

Update 11/17/09: I’ll be moving the Fiat out tonight and moving the SS to front row center and starting to work on it again this weekend. All the suspension pieces could be assembled to the car by the end of the year if my plans to get floors in the car work out.

Original Post 5/22/08: I am going to use the parts book terms for these parts so there is no confusion as to what I am talking about.

The front suspension on my SS was lightly assembled without shocks to make the car a roller and it came apart without any problems. Most of the pieces just need cleaning and painting so I will deal with those as a group later, but there are some components that require great care in cleaning and restoring. The lower wishbone is one of these parts because there are several critical systems tied to it: the bushed suspension support pivots, lower ball joint, suspension limiting rebound strap, sway bar mount and lower spring seat. In this post I am going to look at the wishbone itself with regard to cleaning, and the disassembly of the ball joint. I was advised to leave the ball joints together but this one had enough play that I was worried about it having to come apart later anyway. The parts book has only one part number (101.00.21.030.00) for the wishbone that fits all 101 cars and 2 are required for each car so it must be symmetrical.

The suspension components on my SS were treated with some kind of rust inhibitor that is very hard to remove, requiring a combination of scraping and media blasting. Once I have the wishbone stripped bare I tape over the openings to the support pivot bushings, to prevent blast media from getting into the grease passage ways and I masked the ball joint opening to keep media out and grease from getting in the blast cabinet. For a first pass I spend about 10 minutes removing as much of the loose coating as possible and I focus on the snap ring on the ball joint threaded ring nut. This snap ring has to be removed to thread the ring nut out.

Wishbone masked off and ready to be blasted.

After the first pass in the blast cabinet I (VERY CAREFULLY) use a razor blade to peel off the remaining paint. Once most of it is removed I use the blast cabinet to clean it up. Depending on how stubborn the coating is I may go back and forth between blasting and scraping 4 or 5 times before the part is sufficiently clean. Having exposed the snap ring I scrape around it and use a small screwdriver to remove it. The snap ring is essentially a springy ring that clips into a groove on the ring nut and has an end that goes into a hole drilled into the threads between the wishbone and ring nut. Once everything is clean and the snap ring is removed, I apply some Kroil to the exposed ring nut threads to ease its removal.

The corner of the razorblade is pointing to the part of the snap ring that goes into the hole in the threads. You can see the accumulation of grime that has to be removed to get at the snap ring.

The ring nut has two holes to accept the special pin drive tool required to remove it. I didn’t have this tool so I borrowed one from one of my local Alfa experts and used an electric impact driver to remove the nut. I didn’t remove the grease nipple first which was a mistake, because it turns out there is a spring attached to it on the inside that helps direct the grease deep into the ball joint. I don’t know how critical this spring is, but I am going to try and track one down before I put this all back together.

The home-made special lower ball joint removal tool: a socket with two dowels welded to it. Thanks Conrad!

My first look inside theball joint. Note how clean the wishbone got after about a half hour of scraping and blasting.

The ball joint assembly is cleaned in solvent and inspected. There is some wear on the ball, easily seen in the picture below, and three shims. I suspect that removing one or two of these shims will cause the two cups that surround the ball of the ball joint to be closer together when assembled and thus take up the slack I felt. If I do this then the two sides of the hole that the snap ring goes in will not line up anymore and I will have to drill a new hole in the threads. Half of the hole can be seen in the threads of the ring nut in the picture below.

The wear is evident on the ball in this picture and you can see the thread locking feature the snap ring end goes in in the threads of the ring nut.

I am going to get the other wishbone to this point and do research to find out the best way to deal with the slack in the ball joint, the grease nipple and and snap ring. Once I know how to proceed I will write part 2 of the wishbone saga.

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