alignment issue on w124
 

I went for an alignment yesterday (not an MB shop but a very reasonable and knowledgeable shop) and literally spent time with the alignment guy under the car, he has a fancy hunter laser machine, but the data for the w124 in that machine was incorrect (its incorrect in all of them according to the operator), when we chose the base model it was giving specs for an E420 or E500 I think.

So I used the factory manual specs for my car which were

camber 0° 5'
caster 10° 10'
toe 0° 20' - with spreader bar (two pieces of wood slightly cranked with a jack)

Dialling in the caster and camber requires constant toe adjustment unlike regular cars, we got the caster dialled in exact dead correct but the camber on the right could not be dialled in (the eccentrics were fully cranked in) and still we had +1° 3' camber. with zero toe

What can cause this - worn strut mount? or sagged spring? - we went around and checked the car, it was completely level and he used a tool to measure the arm angle - it was similar on both sides.

I inspected the spring pads and found two nub pads on both sides on the front and both the strut mounts show very fine cracks at rest.

Several things can cause the excessive negative camber. Worn c-arm bushings, worn ball joint, bent strut, bent spindle, bent chassis, as well as the afore mentioned sagging spring. I wouldn't suspect strut mounts so much, I think they would be obviously bad if affecting the camber a lot.

A lot of cars use the strut mounting to the spindle as the camber adjusting point. When my wagon was having camber issues I notched the upper bolt hole in the new struts to be able move it to get a bit more camber adjustment. I only enlarged the mounting hole 1-2mm and it turned out to be a lot more adjustment than I needed to get the spec I was after.

My 4-matic uses a slightly different mounting of the strut to the spindle but I think the same tactic can buy you a bit of adjustment. If your stuts aren't relatively new, I'd go ahead and replace them. They aren't stupid expensive, and well lets face it you can't have struts that are too new. You could notch the upper bolt bolt a small bit or just put them together as-is pre-loading the assembly in the positive camber position before tightening everything up.

the ball joints are a week old (lemforder parts) - I think I 'll have to mount the spindle on a chuck to see if its bent out of shape, We checked the arm bushings with a tool that is usually used on old GM and Ford cars its a claw shaped thing It pulls the arm and verfiies bushing flex - there was zilch flex (these MB bushings may look tired from outside but they are solid even after nearing 2 decades)

anyway - Im more leaning towards on the strut mount being fatigued as its very common practice to use camber plates on cars that do not allow adjustment like ours.

darn it

I got it backwards, I have negative camber problem,, speak of dozing on medication. :o