1972 450sl steering box adjustment. - PeachParts Mercedes-Benz Forum

JOHN GEORGE · #1 12-18-2009, 08:35 AM

Has anyone had experience adjusting for play in steering. Does the allen screw and lock nut on top of the box provide adequate adjustment?

t walgamuth · #2 12-18-2009, 11:51 AM

Usually. Loosten the 19mm lock nut, and back the allen bolt counterclockwise until you feel it binding on center and back off til it is free. Lock it back down.

My car has over 300K on the chassis and the adjustment makes the steering nice and tight with negilbable play.

230/8 · #3 12-18-2009, 12:06 PM

Have done it on my car and there is a lot of improvement possible if your steering box is the culprit...by that I mean there is no other worn part in the steering system that is the source of your play. The lock nut is a bugger to loosen, and once it is loose, you need to hold it tight and turn the center adjusting screw anti-clockwise to remove the play. Do this carefully; make your adjustments in small increments based on the play at the wheel. Mark the nut and adjusting screw with a paint mark to gauge how much you have tightened the assembly, and place a witness mark on the housing for reference as well.

If you have play that is just over the limit of the book specification, just tighten it a tiny amount, about 1/8 turn maximum. Snug the lock nut and drive the car to see if you have helped the issue. Be watchful for binding of the steering gear...you must have the wheel return to center when you release it in a turn. If it fails to do this you have put too much friction in the steering gear. There is no hard fast rule on this adjustment business. Some folks caution you against ever trying it, but others, like me have greatly improved the situation by removing the slight amount of wear that accumulates over 30+ years of use. I ended up tightening my steering ear about 3/4 turn and it is now a pleasure to drive the car...no more wandering down the road. Keep in mind that play in all the other system parts will also contribute to play at the wheel.

Getting at the lock nut is the hardest part. I use a 1/2 inch drive swivel head 19mm socket on a T-bar to loosen the nut and then a crow-foot to hold it while I use an allen socket to tighten the screw. The tin heat shield must be removed from the manifold and then you can barely see the area you need to get at. As I said, it is a bugger and time consuming to make the adjustments in small steps.

Tightening down in one motion to the bind point and then backing off a bit, as suggested, may work for you, but it does not for me. My steering box seems to have a "softness" in the adjusting screw tension that makes it difficult for me to tell when I've hit that sweet spot for binding. So, I just do it in small steps.

Good luck with this project...

meltedpanda · #4 12-19-2009, 10:00 AM

READ THIS
Here is my issue - steering box adjustment 72-450
try the adjustment but do not overlook this part and the front end steering components