Idler Pulley installation ??
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Joined: Jul 2005
Posts: 3,174
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From: London, UK
No longer stock '06 E55, A3 3.2 Quattro, GLE 400d, R107 280SL, Golf Polo
Idler Pulley installation ??
So installed the idler pulley set on the car as I had quite a bad idler on the SC side (the one where the serpentine and SC are on one fitting).
Replaced all and went together ok, but now I have a squeal like never before on cold start. Once warmer the squeal eases and then I get the sound of rattling bearings. Then that goes away.
Really sounds like a bearing and not belt slip.
I spin each pulley and it feels super smooth. No rattles, no binding .. just fine.
I've isolated the squeal to the serpentine circuit. Can it really just be belt slip?
Belt looks fine ... but what I really dont like is the sound of rattling marbles soon after the squeal has gone!
Any thoughts?
Replaced all and went together ok, but now I have a squeal like never before on cold start. Once warmer the squeal eases and then I get the sound of rattling bearings. Then that goes away.
Really sounds like a bearing and not belt slip.
I spin each pulley and it feels super smooth. No rattles, no binding .. just fine.
I've isolated the squeal to the serpentine circuit. Can it really just be belt slip?
Belt looks fine ... but what I really dont like is the sound of rattling marbles soon after the squeal has gone!
Any thoughts?
Last edited by stevebez; Feb 15, 2020 at 10:51 AM.
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Joined: Apr 2016
Posts: 202
Likes: 30
2005 C55 AMG (sold), 2005 E55 AMG
I'm assuming you took the SC belt off to start the car and the sound was still there? A failing bearing usually sounds like rattling marbles. Since this only happened after installation of the new idler, maybe it came with a bad bearing? The only other thing I can suggest is to check that the double idler pulleys were installed correctly. IIRC the C-clip is supposed to face the front of the car on both pulleys. When installed backwards it's very hard to tell by eye
