alkrstev

Hi guys. My car has developed a slight wobble on my coolant pump pulley which is #8 in the attached picture. My crank pulley is also wobbly as well, but what worries me more is the coolant pump pulley. I had just replaced my spark plugs and switched my ic pump to the CM30 johnson pump. I think I need to replace my belt too since I got 70k on it and the car is an 02. Also, I dont know what it is called, the metal thing in the middle of the supercharger pulley is not centered and wobbly as well. My question is: Have any of you guys experienced any of these problems, and do you think changing the belt might fix them? I am getting some noises when I start the car (cold start), but once I spray some WD40 on the belt, they go away for a little while. I am really worried as I am out of warranty and the car is giving me problems. On second note, I been having some acceleration issues (TPS), and wanted to replace the gas pedal assembly, but mercedes dealer quoted me $230 for the gas pedal assembly and $85 for the belt. Could it be cheaper anywhere else? Thanks for your opinions.

loudandheard

I can tell you from personal experience I was never able to get the "washer", the large medal thing in the middle of the supercharger pulley, completely leveled when I replaced the bearing, even my pulley had a slight wobble. I have run it like that for quite a while with out any problems. As for the other pulleys, they seemed to be wobble free.

You can easyly check the pulleys by taking off the belt, but you will need an e11 socket, I think that's what it was. It some sort of inverted torx socket. Took me for ever to find one in town, finally had to order it off the internet. I was out of a car for a week because I managed to take off a pulley and the belt, but could not put them back on.

This should be an easy fix if it is loose or not tightened correctly. Definitely watch out for those pulleys, they have a tendancy to seize and break off completely.

Get a mechanic's stethescope or a rubber tube and put it up to the pulleys in order to see which one is making the noise. You will need to have the car running and of course be careful. I bet it's the super charger bearing going bad causing that noise.

I would stay away from putting wd40 on the belt, could cause unwanted problems with the belt or even slippage.

Parts.com will have alot of parts for a very good price. Just search for the part numbers or look up the parts for your vehicle.

Good luck!

320 dreamer

#1 never spray wd40 on the belt. just causes slippage issues
#2 my c3 pulley install had no issues with the washer causing wobble. check ewasher for flatness.
#3 is your w/p pulley bearing is bad you need to change this immediatley as a bearing seizure will cost far more than the pulley itself

alkrstev

#1- Just did that as a test to check if it is the belt making the noise or the pulleys. By the noise stopping after spraying WD40, means that it is the belt that is going out.
#2- I havent noticed this before as it was wobble-free this summer when I looked at it. I have a stock sc pulley. I will definitely take it easy on the car until I get this tightened.
#3-You are right that I need to do change it, but I just want to verify that it can be tightened instead or has to be replaced completely.

Thank you for your response 320 dreamer, and by the way, how much would a washer pulley cost?

alkrstev

I am going have to take my car to a mechanic to see if I can get all the pulley's tightened. It makes me feel better that the metal thing not being leveled on the sc pulley is not going to be a problem. After all, mercedes dealer was the one who installed the new sc pulley under warranty about a year ago. My car is stock with only CM30 pump, k&n's, and NGK IX plugs. Thanks for the advice. I will try to take some videos tomorrow and post them to better show the problem.

evilsaint

Try www.autohausaz.com for cheap OEM parts too. They usually ship pretty quickly.

320 dreamer

belts run about 50$. if in doubt change it
the washer for the s/c pulley is ........wait for it..........1000$!!!!!
you have to buy the whole pulley kit to get a washer.
also DO NOT TRY TO TIGHTEN the s/c bolt without a torque wrench. 20 NM torque and no more. its a hollow bolt and will break if overtorqued. again the bolt is 1000$

c32AMG-DTM

The waterpump pulley (#8 in the diagram) is a solid piece of metal and does not have a bearing to seize - so bearing seizure is not an issue. If that pulley wobbles, check the pulley for structural integrity, and if it passes that, check that it's been properly tightened.

alkrstev

I guess I will try to tighten the pulley and check the rest of the pulleys just to be safe. I hope the sc pulley is not going to give me any problems.

evilsaint

I could have sworn LET or Eurocharged or somebody was selling a solid version of that bolt... maybe just the washer too. Check on Parts.com, AutohausAZ.com, etc, and maybe call around to parts shops. It doesn't seem like that could be the only solution to replacing the bolt/washer...

320 dreamer

theres a reason the bolt is hollow. not sure why but they didnt do it just for grins. eurocharged doesnt sell a replacement bolt for the s/c. neither does needswings.
parts.com autohauz sells it in kit form just like m/b. i have been looking for 6 months for a spare oem bolt just to have, none to be found.
most use a solid bolt and doesnt seem to be an issue i just like the right part for the job

alkrstev

Ok, I took a short video of my sc pulley, and tried to record the wobbly water pump pulley, but it was not as wobbly as yesterday, its weird. This video was taken at cold start, and you can clearly see the wobbly supercharger pulley and the metal thing in the middle is off balance. Click on the link and I am very SORRY for the bad video quality. Things seemed better today and the pulies seemed more normal.

http://www.youtube.com/watch?v=Lfe_92lNDPU

320 dreamer

dude hold the camera still!! cant tell if anything is wrong with the camera moving all over the place

alkrstev

Sorry, I did not realize I was moving around way too much. I will take another video and will try my best to make it clearer.

alkrstev

This video is a little bit better although still recorded by phone. You can see towards the end of the video the wobble of the w/p pulley and crank pulley. Let me know what you think. I tried to tighten the four screws that are on the w/p pulley, but it did not help. You can also see the belt move left and right in the wp pulley at the end. Maybe replace the belt???

http://www.youtube.com/watch?v=uYKOFOv8h_U

gt4awd

I would start with the belt. The pulley wobble could be an illusion caused by movement on the belt...

alkrstev

You are right gt4awd, it would also be cheaper to buy a new belt and go from there. I got 70k on the original belt and need to replace it anyways.