adjusting freeplay in steering
 

RE: 1985 300TDT - I've done searches on this forum, but can't find the answer to this question. When measuring and adjusting the freeplay in the steering box, should the engine be running?

I have never adjusted the steering ger box on 123's with the engine running. After the adjustment, I always check with the engine and PS working.

I read somewhere that the wheels should also be off the ground, but I don't know if that is true or not.

Be careful not to over adjust (counter-clockwise) the adjuster too far or you can dent the recirculating balls? I believe this is what happens.

Free play, steering wheel centered, is I believe 25mm.


Haasman

Hello Tod,

My Indy told me that the adjustment of a W 124 steering box should be performed at the workbench so I am not certain that it could be done on the car. Even worse : in any of my documention is there a mension of an adjustment.
He told me also that MB prescribes the replacement of the steering box on a W 124 every 300000 km !?!?
Mine, with the front wheels straight ahead, hasn't any play after 326000 km so I am not to worried about it .

Danny

123 model series steering gear boxes can be adjusted in the car.

Haasman

Adjust with the engine off. Why risk your safety? Remember to loosen the lock nut first before turning the allen screw CCW. 25mm is max play allowed at the rim. More than that and you have worn steering components or a worn box.

Thanks. Do you do it with the front wheels off the ground?
Do you measure the freeplay (1 inch) of the steering wheel with the engine on or off?
Or does it mater?

you can measure the play with the engine off....in fact it's probably better that way as you can really feel the resistance when it starts. with the engine (and therefore the power steering pump) running, it may mask the point at which the slop in the steering ends.

note: don't forget to make sure that your steering lock is relased :)

I have always done it with the wheels on the ground without any problems.

Refer to the manual
 

In the 107 Chassis manual (complete description of the work) it says to pull the pitman arm off the output shaft of the steering gearbox. Attach a divice to the steering wheel and measure the torque. There is a maximum torque value not to exceed. This is torque of the steering box, not connected to the wheels (or anything). THe value is something like 110 N/mm.

The output shaft is on a tapered gear and the adjustment snugs the gears deeper into the tapered teeth. If it is too tight it binds and wears the bearing surfaces in the gearbox case. Better a little too loose than too tight.

Regarding steering play, after adjustment there may be a low torque value in the middle of the range and that is acceptable for a steering gear not adjusted for a long time.

and one other thing!
 

Also, again be sure the steering wheel (wheels et al) are centered. This series has considerable play in the wheel off center.

Haasman