Upper Control Arm bushing repair

[BHap]

I was told at my last state inspection that my outer, upper control arm bushing on the right side is starting to show some "play" and should be replaced.  How difficult is this job? My mechanic told me that the other components looked good and that the one bushing is all I needed to replace.  I am wondering if there is anything else I should replace while I am doing this.  Any thoughts on difficulty and other things to do / check?  This is a 1970 280SL with about 50,000 miles.....

[ja17]

Hello Bhap,
This area at the top of the kingpin contains two steel excentric bushings in the upper  control arm at the king pin. The king pin also has a steel bushing which threads into it and an excentric upper "link pin". This entire assembly is used to adjust front end caster and camber.
This area usually is first to wear. If it has been greased from time to time you may be lucky and only need to replace a bushing. If the assembly has been left ungreased wear and rust damage occure. In these  cases the king pin assembly, upper link pin assembly and lower trunion assembly may need replaced. Hope you get lucky. If you need to put the work off for a while. Have the front end greased right before your next inspection, The grease will temporarily tighten everything up! But remember this is a safety concern, don't put it off too long or something may break!

Ericmarciano on this list just went through this project.

Also make sure that the play is not just a loose wheel bearing. 50,000 miles is a little premature for this kind of problem unless it has not had its regular chasis lube service.

Joe Alexander
Blacklick, Ohio

[JimVillers]

Bhap ... The job is not too hard ...... if the parts are not rusted solid.  By jacking under the lower A-arm, you can take the pressure off of the upper bushing to remove and replace it.  The eccentric that was mentioned controls the wheel camber so you will need to have an alignment when you are finished.  You might read this thread from the 190SL Group site since the job is identical on the two cars.   http://www2.190slgroup.com/showthread.php?s=&threadid=2462

Jim Villers
190SL, 230SL 5-Speed, 190E 2.3-16 Kompressor