Toadster

yes about 1/2 inch: 505 vs 510

http://www.gates.com/oreilly/PDFs/SizeListings.pdf

Toadster

ok - you can really hear it in this video, much better HD camera

berti_00

sounds beast

Toadster

maybe i'm just paranoid?

the technicians at the MB garage noticed the sound - maybe just more noise from the aluminum pulley? hmm....

Lawrence1

Sounds like a noisy bearing... possibly one of the idlers. Take the sc belt off and start the car to check if noisebis still there. If its still there move on to the other belt and do the same. This should help you narrow it down

Toadster

yah, i guess that is possible - would expect more 'chirps' with the bearings, but who knows, I'll have to give it a few tests...

ghettoroadster

did she feel any tighter?

Toadster

nope, the tensioner moves WAY more than I thought, had zero issues getting the belt on

WHTEVO

I am thinking it's because the belt is alot tighter. Maybe try swapping the old belt on and see if the sound is still there.

Toadster

Shardul's suggestion was even 1/2 inch tighter with the K080496HD
stock is 510 and I put on the 505

I'll do another try later today without the S/C belt

Critter

Initially thought the noise was the idler beside the charger pulley , but when you shut the car off at the end of the video it looked like the bolt was still turning and so was the noise being there also. Get someone to shut off the running engine while you watch that bolt at the end of the supercharger.

Manuyc

Looks good and sound good

Toadster

interesting at :38-:40 you see the bolt spinning...

is this normal operation? I'd assume yes as you really wouldn't want the S/C to stop really hard

Critter

Manuyc, how can you say it sounds good, listen closely and watch when the belt stops at the end of the video (38 seconds) the sound continues until the bolt stops. I have a coffee bean grinder that is quieter than this noise.

Critter

Sorry guys,
I do not have one of those spinney things on my engine, but is there a bearing inside of the clutch, if yes then it is on the way out.

Toadster

hmm - the clutch was new with the pulley - not saying it can't go bad, but it's been ~14k miles

Critter

Toadster, Just trying to help, if you have a mechanics stethoscope put it on the end of the charger casing and then start then shut off the engine as in the video, now listen to the vanes and clutch slow to a stop, this noise I believe will be the clutch bearing or there is no oil in the charger housing. The new belt being shorter could be putting a little more stress on the bearing which would change the bearing load. If you remove the belt and spin the clutch itself you may also hear a bearing noise, in this case put the scope on the charger clutch bolt and spin the pulley. Good luck, better to replace the bearing instead of having it come loose at speed.

berti_00

thats what she said aighhhht

PTE

Take a new un-wet Bar of Ivory soap. With the engine Idling , Run the bar of soap up against the grooved side of the belt just before the Blower pulley. Push it to the grooved with some pressure . If the Noise quiets down , Then the belt needs some break in time. I find alum Pulleys tend to be a-bit noisier during break - in / seating time , than Steel . It will quiet down .
Cheers _PTEngineering

Critter

PTE, Just what is that noise at 38 seconds after the engine and green belt have stopped, soap will not correct that sound, ever.

PTE

That is the noisy *** bearing in the Driven pulley on the front of the Kompressor I you watch real close , it is in time with the engine And after the engine stops running the Kompressor is still rolling and there is the noise to go with the rotating shaft. you got a sharp eye. I was going on the fact that he noticed the noise after the belt change , but it was not there for the belt change?
Cheers _PTEngineering

Toadster

So bad bearing.... Dang. At least not too expensive- who has a spare? :-)

Critter

Well guys. it is always a good day when you find the problem in the driveway and not fifty miles from home in the dark of night.

Good luck with the bearing change, if when you have the belt off spin the idler beside the charger pulley with your finger, if it spins for quite a while then change it also, call it preventative maintenance.

berti_00

that should have not gone bad in such low mileage usage... my stock pulley had 70k plus and i dont think it was never changed and it was smooth as a babys bottom

AMG E Power

+1 I was thinking the same exact thing. You might want to contact who u bought it from to see if they can help .