Alignment problem steering will not return to center - PeachParts Mercedes-Benz Forum

vstech · #1 03-19-2012, 01:03 PM

not on it's own at least.

I figured it's likely the alignment, but the power steering pump was nearly empty, so it could be related to that as well.
it's in a 124 wagon, so PS pump replacement is not affordable without finding a wagon in the yard...
89 specifically.
it's a customer's car, and he's had it aligned, but it's still stiff. I told him to take it to MB dealer, but he's afraid to...

Stretch · #2 03-19-2012, 01:14 PM

First fill that pump!

With weight off the ground - how do the wheels feel? Meaning - can you turn them right and left by hand easily?

Repeat process with weight on ground on slip plates => you know how to make slip plates don't ya?

Diesel911 · #3 03-19-2012, 02:14 PM

Quote:

Originally Posted by vstech

not on it's own at least.

I figured it's likely the alignment, but the power steering pump was nearly empty, so it could be related to that as well.
it's in a 124 wagon, so PS pump replacement is not affordable without finding a wagon in the yard...
89 specifically.
it's a customer's car, and he's had it aligned, but it's still stiff. I told him to take it to MB dealer, but he's afraid to...

If he had it aligned recently and the Wheel was centered before the alighment he should take it back to the Shop and let them Fix it.

In post number 4 of the Thread below is a Pin that Screws into the bottom of the Steering Box an when installed correctly holds the Steering Box in the mid range where the Wheel should be centered.
When you adjust the Toe-in it is a good idea to have that pin installed since everthing should be centerd when the Power Steering is centered.

Steering wheel not straight

If the Power Steering Pump badly ran out of fluid and something was damaged you would think it would be making noise or seeze up.

Was the alignment done to try to correct the Steering Wheel or was the alignment done because there was an other issue.
If it was done because there was another issue something is worn out or bent up front; or, assembled wrong.

Biodiesel300TD · #4 03-19-2012, 03:30 PM

Are the 124 steering boxes adjustable like the 123s are? If so, if it's adjusted to tightly the wheel will not return to center. I adjusted my 240D box quite some time ago to get rid of some of the play. When I R&Red my front end, the steering was much tighter and then the wheel wouldn't come back to center on it's own, so I readjusted the steering box to get it back to normal.

shertex · #5 03-19-2012, 03:46 PM

Ball joints will also cause that symptom. I thought my steering not self-centering was an alignment issue, but it turned out to be ball joints.

compu_85 · #6 03-19-2012, 05:00 PM

I also noticed this problem... it's called memory steer... on a W124 with a bad ball joint.

-J

vstech · #7 03-19-2012, 05:50 PM

the pump was not dry, just very low, and of course I filled it, thanks!

ball joints make good sense, are they replaceable on the 89? I'll quote him the issues and consequences... thanks!

mach0415 · #8 03-19-2012, 06:20 PM

Based upon my experience, SAI is the cause for a "no return to center" after making a turn. I have a 1999 Suburban 4x2 that has this issue. It has SLA, but the ball joints are okay. My suspicion is a camber and another combined angle dimension being out of whack. An alignment from an experienced MB tech may be in order to catch which angles are to be/can be corrected.

Steering Axis Inclination (SAI) is the measurement in degrees of the steering pivot line when viewed from the front of the vehicle. On a SHORT-LONG ARM (SLA) SUSPENSION the line runs through the upper and lower ball joints.

On a MacPherson strut suspension; the line runs through the lower ball joint and upper strut mount or bearing plate. This angle (SAI), when added to the camber to forms the included angle and causes the vehicle to lift slightly when the wheel is turned from a straight position. The vehicles weight pushes down and causes the steering wheel to return to the center when you let go of it after making a turn.

Like caster, it provides directional stability and also reduces steering effort by reducing the scrub radius.

If the Steering Axis Inclination (SAI) is different from side to side, it will cause a pull at very slow speeds. SAI is a nonadjustable angle, it is used with camber and the included angle to diagnose bent spindles, struts and mislocated crossmembers.

The most likely cause for Steering Axis Inclination (SAI) being out of specification is bent parts, which has to be replaced to correct the condition. On older vehicles and trucks with king pins instead of ball joints, Steering Axis Inclination (SAI) is referred to as (KPI) King Pin Inclination.

vstech · #9 03-19-2012, 06:39 PM

the alignment was an attempt to correct the stiff steering, and lack of return. I'll pop the tie rods, and feel the ball joint force, if stiff, I'll recommend replacement, if smooth, I'll recommend a MB certified alignment!