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Replacing Tensioner/Idler pulley on 1.8L C230
I was wondering if anyone here has any instructions on how to replace the idler and tensioner pulley onthe M271 engine (1.8L Kompressor)? It has gotten pretty bad since my initial problem with rough idling and noise making with the A/C being on and sound like a metal-ish screeching type noise.
Any chance any one here has knowledge or experience in replacing both parts? Tools needed and instructions will be greatly appreciated!
Here is the closest "instructions" i've came across Searching the Forum.
https://mbworld.org/forums/c-class-w...30k-coupe.html
-Chris
https://mbworld.org/forums/c-class-w...ompressor.html
Is it the idler or tensioner pulley? And if it's the tensioner then mine is just the pulley and not the tensioning spring because it's still very tight.
I've got the MB service manual so I could possible tell you how to do it.
Thanks,
Robert
Last edited by rabney72; Sep 1, 2010 at 09:56 PM.




I looked up part numbers for both front and rear alternator bearings for the alternator, but I wonder how difficule it is to replace it DIY or is it better to bring it to an alternator repair place.
If anyone can provide instruction on doing both pulleys, thatll be great! The idler looks easy. It seems like a simple screw at the center of the pulley is all you need to remove. The tensioner pulley is what's got me scratching my head. Don't even know where to start. Excuse my text if it's not spaced, I'm using my iPhone which fails to space words typed at times.
-Chris
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But I would identifiy which ones are bad first. Loosen the serpentine belt so you can spin all the pullies separately. Spin each one, the pulley that make noise when you spin them are the ones that need to be replaced. Then you can just replace them all at once.
I'm usually in oc chilling with friends, if you want to meet up, but i have most of the tools at my house.
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But I would identifiy which ones are bad first. Loosen the serpentine belt so you can spin all the pullies separately. Spin each one, the pulley that make noise when you spin them are the ones that need to be replaced. Then you can just replace them all at once.
I'm usually in oc chilling with friends, if you want to meet up, but i have most of the tools at my house.
-Chris


Last edited by seagel1000; Sep 2, 2010 at 11:34 AM.
http://www.rmeuropean.com/Part-Numbe..._85E85BAC.aspx
http://www.rmeuropean.com/Part-Numbe..._85E85BAC.aspx
(verify it's for your vehicle year/model first before purchasing)
The idler doesnt look hard at all, it is the Tensioner where the real work is.
I would just replace the alternator assembly rather than fiddle with the bearing; it's not worth it.
I referenced my diagnostics to this thread:
https://mbworld.org/forums/c-class-w...udio-file.html
I referenced my diagnostics to this thread:
https://mbworld.org/forums/c-class-w...udio-file.html
I just have a hard time believing that this is the issue. I mean, I never get the noise when the ac is off.
It'd be nice if someone had this issue and knew the exact solution.
I guess I can try it and if it doesn't work take it back, but it's such a pita of work....
I just have a hard time believing that this is the issue. I mean, I never get the noise when the ac is off.
It'd be nice if someone had this issue and knew the exact solution.
I guess I can try it and if it doesn't work take it back, but it's such a pita of work....
I personally wouldn't know what it could be but after reading many posts and threads about pulley tensioners being the "number 1" culprit for the sounds we're experiencing, I'd rather give the idler and tensioner replacement a shot before I replace an alternator.
If you can get a hold of the steps in your MB manual and hand em over to me, I'd be glad to give it a shot and see how it comes out for me. I don't think anyone else here has more problems than me as far as the noises go and the vibrations and the rough idle. All I do know is my A/C noise and rough idle at cold starts is getting worse. Eventually it seems like the car is going to need a bit of gas pedal action to keep it alive which doesn't sound like something I want to experience.
Last edited by seagel1000; Sep 4, 2010 at 05:15 PM.
I just have a hard time believing that this is the issue. I mean, I never get the noise when the ac is off.
It'd be nice if someone had this issue and knew the exact solution.
I guess I can try it and if it doesn't work take it back, but it's such a pita of work....
I found the alternator on oreilly autopart's website for 180, probably their brand and rebuilt but, it comes with a lifetime warranty whereas the german ones dont.
I'll see what I can do about posting the instructions. (not sure how to save the program instructions to a pdf)





