after getting my harmonic balancer replaced, now the belt tensioner needs to be replaced on my 1998 C280. the tensioner itself starts wobbling around and makes a clicking noise whenever load is put onto the belts. i went to a european car mechanic and he said its going to cost $238 for the tensioner and $200 for 2 hours of labor.

1) am i getting ripped off?
2) if so, is it a difficult job to replace this belt tensioner (can i do it as a DIY)?
3) does the tensioner going bad have anything to do with the harmonic balancer?
4) is it normal for the tensioner to crap out at 70,000 miles?

Common problem and thats a premium price. You would save a lot doing it yourself and it is a low risk job. Not much to do wrong.

__________________
Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician

I agree with Steve is a DYI job relative easy to do I recently change the belt, belt tensioner, tensioner shock, on my 95 E 320.

It sounds like your tensioner is bad so probably the belt is loose and easy to pull out. Take the fan cover/shroud out, if the belt is in bad shape just simply cut it and pull it out, if not then loosen the belt tensioner adjusting bolt, and pull the belt, take off the three bolts holding the fan blades (more room to work), take off the main bolt that holds the tensioner to the engine frame, pull the tensioner out, take off the tensioner shock, replace with new parts. You may want to consider while you are at it putting a new belt, and new tensioner shock, they are not that expensive, and you can always keep the old belt if still in good shape as a spare in the trunk of your car. You will need Metric tools, a set of Open Ended wrenches, Allen wrenches or Allen bids, and a decent Torque wrench. I used Loctite fastener (red label) on all the screws and bolts when I was putting things back together just to make sure nothing can work itself loose with the vibration of the engine. I wish I could show some of the pictures of the job I did but I have not been able to reduce the files enough so that I can post them in this forum.

My suggestion would be to contact Phil from Fastlane (the forum sponsors) that's where I got my parts at a very reasonable price. And you are right the prices from the dealer tend to be more, but if you look around you can get better deals. By the way, as reference material I bought both the Bentley manual (for my car) and the CD’s use by the Mercedes technicians they come very handy. Good luck

Bluerio

PS>> search the forum, there are many threads on this subject

Hi rice, $200 labor is pretty steep. It's a real simple job for a DIYer. The job described by blueriomedina is for a 104 engine. The 112 is much simpler. Like Steve says, it's a low risk job. Give it a shot.

i just sifted through 30 pages of search results and couldnt find anything maybe im a poor searcher.

can someone give a general overview of the steps needed to replace the belt tensioner on the m112 c280 engine, or post a link up to a thread i missed while searching, please??