89CE

Hello everyone. I need a small favor from the ML crowd. Would you guys mind looking in the engine compartment and verify that the the belt tensioner pulley is not supposed to be moving when the engine is running. An independent shop says its normal for the tensioner pulley to be moving a bit (up and down motion) because it is self-adjusting. The dealer says that it should be fixed and not moving. Would you guys please help confirm this? Thanks in advance.

andaya

Not sure if it suppose to sag, if that's what you mean. I will run the engine, pop the hood and will take a picture for you. I will post tomorrow morning, if I my wife doesn't take the car DOH!

f4i 954

Ther will be slight movement from the tensioner.
If ther is someting wrong with the tensioner it will be noisy.
If it sounds normal leave it.

89CE

Thanks for the input. Yes, there's a slight movement on the tensioner itself. Im trying to loosen it so I can change my belt, but dont know how this thing operates. Im afraid that if I take the nut off, that I might have a problem refitting the new belt. Ive been searching this forum and asked a number of times for help but no luck. If anyone has any additional input, please let me know. Thanks.

andaya

Also you can look at a quick vid I took. Hope this helps. If I were you I would let a garage do it, They have a special gun to measure the tension and also the timing. If you do it you might end up spending more money then what you started with.

http://sxpress.com/~jim/ml430/ml430.AVI

f4i 954

What engine do you have? If your talking about a 89 CE, there ia either a 10mm alen or 19mm bolt right below the tensioner that as to losen before backing up the tensioner with the 13m rod.
This is not a easy one to play with.

andaya

thread. I didn't realize he had an 89 CE.

Wrong place man.

89CE

Userid doesnt necessarily mean its the car Im talking about. Im aware that this is the ML forum, because I do also own an ML. I guess the confusion stemmed from my original post where I didnt make any reference to an ML. So to clear it up, I am on the right place and Im asking help for a 1999 ML320. Thanks.

Andaya,
Thanks for the link you sent. Although I couldnt really tell if the tensioner is moving freely...could you tell me if it is?

f4i 954

Ignore mi last post.
On the ML all you need to do pull the black cap on the tensioner out.
Use a socket to pull the tensioner on the oposite of tension & remove the belt. (inverted torque E10 or 16MM socket).

89CE

I finally got the belt off and put a new one in. Thanks to f4i954's advise. I would also like to thank all that gave input in this matter. I tried using a wrench to loosen the tension but the nut kept on getting loose since the direction of travel is counter clockwise (loosen). I then used the E10 torx and that did the job. I wonder if that would cause the tensioner to loosen.
Thanks again everyone!! BTW--I did replace the upper pulley as it was starting to wobble. Cost was $40 from the dealer.
You guys might want to check yours to be on the safe side.