85 300TD, installing pitman arm on a new steering box
 

How can I go about re-installing the pitman arm correctly onto a new steering box I'm putting on my 85 wagon? The teeth on the steering box do not seem to have any that indicate exact alignment (ie a tooth that looks different than the others).

I was thinking that as long as the wheels are straight (being up on a ramp) and the steering wheel is straight, that if I can figure out how many rotations the box turns at the top end (where the steering shaft goes into), I can approximate the half way point and then mount the pitman arm (already connected to the tie rod and center link) with the box, though I would imagine it might end up being off by a few teeth on the pitman arm. I'm not sure if that matters much, or if there is a better, more exact way (and yet practical with one person) to go about it.

Ideas?

The FSM file is too large for here, e-mail me.

The output shaft on the steering box does not go round and round - it turns through about 90 degrees or so.

Have a look at this picture

http://www.peachparts.com/shopforum/...djustment1.jpg

from this thread

http://www.peachparts.com/shopforum/diesel-discussion/303379-what-feeling-will-properly-adjusted-w123-w116-w126-power-steering-box-2.html

The marks on the masking tape show how far the output shaft travels from stop to stop.

You'll also see on the end of the output shaft (on the steering box) a mark that should align with the mark on your new Pitman arm.

I hope you've got the correct Pitman arm for your car - reading through the FSM chapter 46-510 you'll see that there are several options / variations on the theme...

EDIT email too many if you don't have a copy. This is a critical component.

I have the Mercedes factory service manual, just hadn't looked yet. The pitman arm is still on the car, I'm just replacing the box. Assuming the box fits the arm.

I figured that since the input shaft (where the steering coupler goes) rotates a lot more than the output shaft (pitman arm end), then it would be a whole lot more accurate to measure the rotations/half-way point via the input than the output. But I'll check the manual and also look on the output shaft to see.

There is an expensive factory tool for centering the Power Steering Steering Box that goes into a plug on the bottom of the Box.
Also used when centering the Steering Wheel.

Factory made in Left Pic; Homemade in Right pic.