Idle pulley?
Thread Starter
Racer
Joined: Jul 2019
Posts: 366
Likes: 17
Idle pulley?
I noticed a bit of a pulley noise last few weeks eap at start up until car was warm. Had routine oil and filter change and went ahear and decided to change the idle pulley. First time it still had a chirp. So i got another one and that one was quiet. Drove it home and today it is chirping like a mad bird again. Did just experience a ton of rain. Could that be a reason?
Drifting
Joined: Sep 2009
Posts: 1,862
Likes: 594
From: Prescott, Arizona
If the harmonic balencer is relatively straight-
The swivel bearing in the tensioner can chirp. A clue you may or may not have is fine aluminum sparkles on the belt.
Probably time to change all the pulleys and tensioner. Make sure the dust guards which look like dished washers are not rubbing when replacing.
Drove two 25 minute sessions at Laguna Seca Sunday, heavy rain, no chirps.
It could also be the AC tensioner, tensioner pulley or AC idler pulley.
The swivel bearing in the tensioner can chirp. A clue you may or may not have is fine aluminum sparkles on the belt.
Probably time to change all the pulleys and tensioner. Make sure the dust guards which look like dished washers are not rubbing when replacing.
Drove two 25 minute sessions at Laguna Seca Sunday, heavy rain, no chirps.
It could also be the AC tensioner, tensioner pulley or AC idler pulley.
Thread Starter
Racer
Joined: Jul 2019
Posts: 366
Likes: 17
If the harmonic balencer is relatively straight-
The swivel bearing in the tensioner can chirp. A clue you may or may not have is fine aluminum sparkles on the belt.
Probably time to change all the pulleys and tensioner. Make sure the dust guards which look like dished washers are not rubbing when replacing.
Drove two 25 minute sessions at Laguna Seca Sunday, heavy rain, no chirps.
It could also be the AC tensioner, tensioner pulley or AC idler pulley.
The swivel bearing in the tensioner can chirp. A clue you may or may not have is fine aluminum sparkles on the belt.
Probably time to change all the pulleys and tensioner. Make sure the dust guards which look like dished washers are not rubbing when replacing.
Drove two 25 minute sessions at Laguna Seca Sunday, heavy rain, no chirps.
It could also be the AC tensioner, tensioner pulley or AC idler pulley.
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Thread Starter
Racer
Joined: Jul 2019
Posts: 366
Likes: 17
Last edited by Bstan1009; Dec 17, 2019 at 01:36 PM.
Le Mans Master
Joined: Sep 2003
Posts: 8,812
Likes: 2,029
From: eastern NC
Bstan1009, you haven't mentioned (at least not in this post) how many miles you have on your engine.
There are a number of other things that could be responsible for a chirp besides the idler. Alternator, A/C clutch, water pump or even power steering. I would certainly check the fluid level in the power steering as a start.
Good luck... GUSTO
There are a number of other things that could be responsible for a chirp besides the idler. Alternator, A/C clutch, water pump or even power steering. I would certainly check the fluid level in the power steering as a start.
Good luck... GUSTO
Thread Starter
Racer
Joined: Jul 2019
Posts: 366
Likes: 17
Bstan1009, you haven't mentioned (at least not in this post) how many miles you have on your engine.
There are a number of other things that could be responsible for a chirp besides the idler. Alternator, A/C clutch, water pump or even power steering. I would certainly check the fluid level in the power steering as a start.
Good luck... GUSTO
There are a number of other things that could be responsible for a chirp besides the idler. Alternator, A/C clutch, water pump or even power steering. I would certainly check the fluid level in the power steering as a start.
Good luck... GUSTO
Thread Starter
Racer
Joined: Jul 2019
Posts: 366
Likes: 17
i applied pressure to the HB and it was solid. While running it appears to be solid as well. Once car wss fully dried out it didnt seem to have a chirp, however i havent driven it in a few days due to constant 24 hour rain last few days. When i did crank it last and leave it idle i didnt here any chirping for first time though.
Thread Starter
Racer
Joined: Jul 2019
Posts: 366
Likes: 17
The car started much more quiet after it had time to dry, however, there is still for sure an annoying squeal/chirp that increases at acceleration. I am going to replace the belt with a gator back this weekend to see if that helps and/or solves the issue. I figure that is the cheapest and easiest trouble shoot from the jump. Idle pulley already replaced, after new belt I will look at tensioner pulley as I know that and idle pulley are lots of the time the culprit and that sometimes soon after you replace one the other tends to go. Ill go ahead and replace AC belt as well. Hopefully its not water pump, harmonic balancer, or anything else serious. I will update my results.
Le Mans Master
Joined: Sep 2003
Posts: 8,812
Likes: 2,029
From: eastern NC
The car started much more quiet after it had time to dry, however, there is still for sure an annoying squeal/chirp that increases at acceleration. I am going to replace the belt with a gator back this weekend to see if that helps and/or solves the issue. I figure that is the cheapest and easiest trouble shoot from the jump. Idle pulley already replaced, after new belt I will look at tensioner pulley as I know that and idle pulley are lots of the time the culprit and that sometimes soon after you replace one the other tends to go. Ill go ahead and replace AC belt as well. Hopefully its not water pump, harmonic balancer, or anything else serious. I will update my results.
Let us know the outcome... GUSTO
Thread Starter
Racer
Joined: Jul 2019
Posts: 366
Likes: 17
Will do! I didn't have much time to look at it yet, but what I did see so far is that the right side of the belt for sure has a little bit of rough edged from fray where the other side of the belt remains totally smooth. I also notice the sound is coming more from the drivers side of the car. The HB looks to be pretty solid from some angles but from others seems to maybe have a barely visible wobble but it could just be because it is moving so fast. The HB has zero give in any direction when pulled on. A Pulley misalignment may have caused the belt to fray a bit, but I will replace that in the morning and see If it corrects the issue even temporarily. I will then ID the true culprit(s) and fix them as well. Praying for an easy fix! I miss this car and I can't stand the sound!!
Thread Starter
Racer
Joined: Jul 2019
Posts: 366
Likes: 17
About to change serpentine belt. Before I do I just wanted to ask some questions. Since.replacing the idle pulley, the squeal/chrip at idle has been greatly minimized but increases with acceleration and decreases with deceleration. It seems to be more on the driver side for sure and the edges of the belt are frayed on both sides. What do you think is the underlying issue?
Thread Starter
Racer
Joined: Jul 2019
Posts: 366
Likes: 17
Fixed!!
Sorry for the late update. I installed a new serpentine belt, gator back, and the sound continued. I replaced the belt tensioner and pulley and it solved the issue!!! So happy for an easy and cheap fix and at least i got a superior quality and newer belt to last me a while. There is still another EXTREMELY faint sound coming from some pulley or something but the original squeal/chirp has dissipated 99% and is only noticeable if i keenly focus on it specifically and intently. Thanks for the tips everyone! It was in fact the belt tensior!
