124 Idler Arm Bushing Replacement
 

Anyone done this? First glance, looks like a pain. May have to move exhaust to get bolt out. If so, where did you disconnect the exhaust (didn't look at that part very close). Suggestions?

I just did this on my '87 190E-16, so this may not be completely applicable, however, the trick is, after you remove the nut, remove the lower bushing, then the upper bushing with the bolt in place. After both bushings are out of their mount, the bolt can be removed at an angle, clearing the exhaust manifold.

Some of them will indeed come apart as Glen described, but some won't. It may have to do with the condition of the right side motor mount.

If it does not, simply cut the top of the bolt off to get it out and put the new bolt, which comes with the bushings, in from the bottom up. You will have to tighten the daylights out of it to get all the slack out.

Hope this helps,

LarryBible~

Any concern with the bolt in from the bottom, the nut coming off and dropping the bolt? Just curious and perhaps a little paranoid for no reason.

Eric...

It's a pain. The pre-cats are in the way. I tried everything. Pulled the bushings, jacked up the motor and such. No luck. Cutoff the head to get the old one out, but there was no way the new one was going in. Ended up removing the rear manifold, which was not as bad as it sounds.

On the next one (friend's car), I used Larry's upside-down method.

Some folks say they can manipulate the bolt around the pre-cats. I think the pre-cats may vary somewhat depending upon the model year in question.

The bolt has to be tightened so much to get the slack out of the bushings that there is just no way that the nut is going to come off and the bolt fall out. Additionally the nut has a bit of a locking edge on it. That bolt is just not going to come out. Have you ever seen a nut come off that bolt even if the bolt is in from the top? It ain't gonna happen if you tighten the bolt enough to take out the slack, period.

To me there is almost no chance of the bolt coming out on my car anyway because at every oil change I pull on all the steering linkage to see that it's tight and that nothing is leaking or falling off. That's why I don't use a topsider.

Good luck,

Larry,
How tight is "tighten the daylights out of it"?
This is a serious question as I have had problems with my 84 500SEL since I replaced the idler bushings. I replaced them and every thing was fine for about a month and then a knocking noise came back on rough roads. I took it apart again ( just checking) and reassembled it and the noise was gone for about a month again. This happened one more time at which time I put locktight on the bolt and reassembled. Guess what, the noise is back.
Maybe I'm not getting the "daylight out of it".
Could you give me a rough torque figure for this bolt?
Thanks

exactly how do you get the old bushings out with the bolt in? I've tried getting them out with the bolt out, and I can't. I just put the new bolt in until I can figure out how to get the bushings out. I am speaking of my SD w116 chasis. What do you guys use to catch the edge of one of the bushings? I am/did do this on a lift, so access wasn't a problem.
Thanks
David

pmechkecknie,

Tighten it until there is no longer any slack. That will most likely be very tight. You will need a long wrench or possibly an impact wrench.

Want 71 280SEL

WIth the bolt out, you take a punch and put it through one bushing, lean it over to catch the other and drive it out. I have never had to apply much force to the ones I've changed.

Good luck,

Thanks Larry,
I'll put the impact to it tomorrow.