Steering Box Adjustment
 

The steering box in my 1987 560 SL has too much play, and I decided to adjust it . A simple enough task but for access. I finally got the lock nut loose (crows foot) but it seems to have become one with the allen head adjusting screw. Can that whole adjusting assembly be unscrewed and removed from the car without causing a problem? Trying to break it loose on the car appears to be impossible (am currently soaking it with PB Blaster and leafing through various religious texts).

Thanks in advance for any help sent my way.

No, to adjust you will have to break the jam nut loose from the shaft w/allen.

Proper adjustment can only be done on the bench so be carefull. Running the adjustment too far will wear out the box quickly.

Steering Box Adjustment
 

Thanks for the quick reply, Steve. As a former mechanic, I've adjusted a number of steering boxes, and have even read up on the procedure in the M-B shop manual. This problem was just a combination of a rusty bolt and almost no access. I finally made some special tools, broke the nut loose and got it adjusted. I checked several times while adjusting (front wheels off the ground), and there was no additional friction going lock to lock. The excessive play, however is gone.

Thanks again for the quick reply. What would I (we) do without this forum?

MadMax

Madmax

How much freeplay did you have and how much adjustment did it take (turns on screw)? Trying to compare with mine.

Steering Box Adjustment
 

The play at the steering wheel was approximately 2-3 inches before the wheels started to move. I backed out the adjustment screw 1-1/2 - 2 turns and checked both the play and the friction turning lock to lock with the wheels off the ground. I haven't driven it yet (alternator being rebuilt), but will check for smooth travel again when I do.

Thanks for the reply. Mine was about half that much but, I still have a very slight dead area in the middle that no amount of adjusting will get rid of.

I had the same problem (excessive steering wheel play) on my 94 E320 (with 100K miles). I had it in for an alignment and asked the guy if he could tighten the steering. He has worked on Mercedes for many years so I thought he knew what he was doing. It seemed like it made a small improvement, but it still had play. A few weeks later I noticed that the steering would sometimes "lock up" when turning hard. It happened when turning into parking lots or when parallel parking. I could also get it to happen by turning the wheel fast from left to right. When it "locked up" it was so tight that I had to use all my force to make a small wheel movement. Since it was now a safety issue, I took it to a Mercedes repair shop. They said that the steering box had to be replaced. Luckily they found a rebuilt one so I was only out $400. So before you start adjusting it, make sure you know what you are doing.

Steering Box Adjustment
 

I'm well acquainted with problem you mention (prior to the widespread use of rack and pinion steering, this was a standard procedure on re-circulating ball steering boxes), which is why I made the adjustment in small increments. I intend to drive the car and carefully look for any signs of friction or binding. Access on the 560 SL is very limited, and required a creative approach and a lot of patience. If anyone wants some tips on doing this, let me know.

I was going to post a thread on PB Blaster, I didn't realize it's availbility was widespread. It is probably the best crud loostener I have used.

Steering Box Adjustment/PB Blaster
 

Its apparently getting wider distribution. I found it at a local auto parts chain store.