W115 steering column problem

[j-galap]

Hi everyone,

I have a W115 steering column issue:

Car will turn right, but not left. Looks like the steering column bracket bolts have stripped. Would this be a case of a whole new steering column (and if so, how to get one/prices?!) or can the bolts be removed and replaced easily enough?

Thanks for any thoughts/advice

[Mike D]

Clarification needed.

Model, year, power steering or manual?

Steering column bolts? Are you referring to the bracket which holds the column to the under side of the dash? If so, then they can be replaced. Use a small die grinder to remove the weld and install new hardened nuts.

Common steering problems are:

Frame rusted at steering gear box mounting. PITA. Requires removal of the gear box and reinforcement of the damaged area.

Broken/snapped gear box mounting bolts. Can also be a PITA if the bolts are broken off flush and you can't grab the broken ends. Box needs to be removed in this case. Do NOT try to "Easy-out" the bolt while on the car. You WILL drill the hole off-center and probably snarf the threads. Use a drill press on the bench or better yet, take it to a machine shop and have them remove them.

Steering "knuckle" or flex joint. Some models have replaceable bushings which can be renewed. You need to either drop the gear box or undo the steering column to get enough movement to replace the joint.

Bent or damaged steering dampener.

Those are the usual suspects. The gear box itself could be worn out but this usually shows as excessive play in the steering wheel.

[Idle]

I ran into this on one of my cars. A 1975 115.

I found the bolts that bolted on the steering box had snapped. All but one.

So I undid the coupling and slid it out of the way. Then I took out the one bolt holding the box to the frame. I then moved the box away from the frame a bit and found the snapped bolts unscrewed easily by hand.

Jack up the front of the car first. And take off the wheel. (Duh)

Then, like a smart guy, I purchased some new bolts from the dealer. They snapped two days later.

Then I found out this was a design flaw that would, with enough miles, manifest itself. Mine started snapping at about 650,000. The fix was an additional steel plate, longer bolts to compensate for the increase in depth of the frame and that fixed it. I found this plate on a car at a wrecking yard, along with the bolts, so I don't know if it was a Mercedes fix or not.

This would be called a gusset plate.

On mine I think there were three or four bolts. I do remember that they were all a different length, so don't mix them up.

But before you start twisting bolts.... Jack up the car in the front and have someone inside turn the wheels. If you see the box flexing then you have the broken bolts.

[Mike D]

Regarding the steering gear box bolts. There is a torque value to the bolts. I believe it is 60 ft/lbs. Should be an annual check item.

[ejboyd5]

Here's a tech note about the bolts. Wouldn't be surprised if it's your problem. A final solution would be to drill all the way through to allow the use of longer bolts and nuts having the appropriate tensile strength.

[Mike D]

Thanks for verifying the torque value.

If you don't or can't find the self locking bolts I suggest using Loctite Blue. The Red holds better but can cause a false torque reading the next time you check the bolts.

[Idle]

I used a torque wrench on mine, but I am guess my situations was too far gone to be repaired in a normal manner.

Like I said, this thing had some miles on it. The guys at the dealership suggested I rebuild it since it was bound to need it but it was running smooth so why?

The tech article does show one thing: These cars need to be maintained. And when they are... They last forever.

[Mike D]

Yup, the old adage is, "American cars need repairs, European cars need maintenance". An ounce of prevention and all that.

[j-galap]

Thanks for the replies! If it makes a difference it's a 1975 230 with power steering!