idler pulley/tensioner/main belt squeak
07-10-2010, 03:06 PM
#1
Melting Slicks
Thread Starter
idler pulley/tensioner/main belt squeak
I've had a persistent squeak coming from the general area of the pulley tensioner pulley that defied exact detection. Use the mechanic's stethoscope to listen to pulley/tensioner bearings, nothing.
Bought both pulleys, main belt, AC belt and for giggles and grins bought a can of CRC Belt Dressing for four bucks. Sprayed a three second shot on each of the belts, both sides of the main belt and the squeak has been gone for a week now. Might have some pulleys and a couple of belts for sale in a week or two.
Charlie
Bought both pulleys, main belt, AC belt and for giggles and grins bought a can of CRC Belt Dressing for four bucks. Sprayed a three second shot on each of the belts, both sides of the main belt and the squeak has been gone for a week now. Might have some pulleys and a couple of belts for sale in a week or two.
Charlie
07-10-2010, 10:12 PM
#2
Melting Slicks
If you have mileage on original belts and pulleys replace em
I've had a persistent squeak coming from the general area of the pulley tensioner pulley that defied exact detection. Use the mechanic's stethoscope to listen to pulley/tensioner bearings, nothing.
Bought both pulleys, main belt, AC belt and for giggles and grins bought a can of CRC Belt Dressing for four bucks. Sprayed a three second shot on each of the belts, both sides of the main belt and the squeak has been gone for a week now. Might have some pulleys and a couple of belts for sale in a week or two.
Charlie
Bought both pulleys, main belt, AC belt and for giggles and grins bought a can of CRC Belt Dressing for four bucks. Sprayed a three second shot on each of the belts, both sides of the main belt and the squeak has been gone for a week now. Might have some pulleys and a couple of belts for sale in a week or two.
Charlie
If you have original parts you may want to replace same.
07-11-2010, 12:28 AM
#3
I've had a persistent squeak coming from the general area of the pulley tensioner pulley that defied exact detection. Use the mechanic's stethoscope to listen to pulley/tensioner bearings, nothing.
Bought both pulleys, main belt, AC belt and for giggles and grins bought a can of CRC Belt Dressing for four bucks. Sprayed a three second shot on each of the belts, both sides of the main belt and the squeak has been gone for a week now. Might have some pulleys and a couple of belts for sale in a week or two.
Charlie
Bought both pulleys, main belt, AC belt and for giggles and grins bought a can of CRC Belt Dressing for four bucks. Sprayed a three second shot on each of the belts, both sides of the main belt and the squeak has been gone for a week now. Might have some pulleys and a couple of belts for sale in a week or two.
Charlie
Cheap fix first before replacing tensioners and such..
11-01-2010, 09:10 AM
#4
Race Director
c5's are notorious for this problem. Go to Autozone and purchase a Gatorback belt and that should take care of the problem. The dealer said it was a wobbling Crank pulley. BS. The crank pulley(harmonic balancer) was fine. I replaced the belt with one from the local auto parts store and it shut up for about a month then the noise came back again..typically on acceleration. Gatorback belt was then changed and I haven't heard a sound in over a year.
Cheap fix first before replacing tensioners and such..
Cheap fix first before replacing tensioners and such..
11-01-2010, 06:19 PM
#7
Instructor
Before replacing bearings and pulleys and things there is one sure fire way to eliminate them as a source for the noise. Spray a small stream of belt dressing or WD-40 on the inside surface of the belt away from pulleys and tensioners. The sound will suddenly disappear eliminating those expensive parts as the source. (The sound will come back however, as soon as the silicone wears off).
My OEM belt began squawking after it was about two years old. Eventually it quieted down and behaved itself. Recently I replaced the belts and am now living with the squawks again. It usually disappears after the car has reached operating temperature.
My OEM belt began squawking after it was about two years old. Eventually it quieted down and behaved itself. Recently I replaced the belts and am now living with the squawks again. It usually disappears after the car has reached operating temperature.
11-01-2010, 06:39 PM
#8
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Gator belt is the only way to cure this I have had the same problem on two cars and once the belts were changed to gator the noise was gone from both.
11-15-2010, 08:24 AM
#9
Race Director
11-15-2010, 09:57 AM
#10
Melting Slicks
C5 Belt Squeal
Possible Causes: in order from most to least likely.
Belts Check the accessory and A/C belts. Dirty, cracked, worn, dry, misaligned... replace. For testing sake remove the main belt and run the engine for a quick minute. If noise is still there its in the A/C drive.
Idle Pulley The early C5's (97-00) had a poor designed idler pulley. It was thin and the washer behind it was flimsy. The washer would deflect and make contact with the pulley making a chirping noise. A stethoscope might help here.
Tensioners The C5 has 2 tensioners. One for the main belt the other for the A/C. Determine what system is making noise before replacing.
A/C Idler I have seen a few idlers in the A/C making noise. Pull the belts off and spin with your hand, if it squeals it should be replaced.
A/C Compressor Yup, I've seen the compressor squeal. Rare, but I have seen it and replaced it to cure the problem.
Alternator Alternators can squeal. Best way to test is to free wheel the pulley, if it squeals replace.
Water Pump, Crank pulley I have never seen the water pump or crank pulley cause a squeal. I wouldn't recommend replacing unless you know 100% that one is the cause. I'd suggest replacing other items prior.
Diagnostic Aid
Belt squeals can be difficult to diagnose. Especially when the squeal is only duplicated/present at a certain RPM/Load. Belts are very sensitive to contamination. Dirt, fluids and chemicals can make them squeal instantly. If there are any leaks from the engine -coolant, power steering, oil, etc... just a drop of fluid can make belts squeal. Also check for a leaking compressor, it can be easily missed. Usually the squeal will come back after replacing the belt if there are any leaks.
Start with visually checking the belt systems. Check the belt conditions and tension. If they check OK then start the engine and take another look. Have an assistant duplicate the squeal. Check for correct belt alignment, check for any pulleys wobbling. Note, the C5 crank pulley tends to wobble a little. If you can hear the squeal try using a stethoscope and listen to each pulley. Do Not place the stethoscope on any moving part. Place it on the bracket the pulley rides on. The squeal should be much more apparent near one pulley than the others while listening through the stethoscope.
Once you find the culprit, replace it. Even if the belt looks OK, if it has not been replaced recently now is the time to do it. Keep in mind the squeal noise might not be coming from just one pulley or belt. It could be from several pulleys or both belts. Sometimes you just cant pin-point the cause, so shooting parts at it is option. Personally I would replace both idler pulleys and both belts for starters. The idler pulleys and belts can be found at most auto parts stores. The pulleys run about $15-$20. The main belt will be around $50, and the A/C belt around $25. The Gatorback belt is good, if you can find one.
How To Replace Idler Pulleys and Belts
This is rather simple and can save you $$. Like I said, both pulley and both belts should run you about $100. One hour diag. plus parts and labor (at a dealer) you're looking at $300. So replacing the pulleys and belts should take you about one hour and will save you a couple hundred bucks.
Tools required: 3/8 Ratchet, 15mm Socket, 15mm Open End Wrench... That's it!
Start by removing the main belt. Take your ratchet with 15mm socket and turn the tensioner towards the engine. Basically you act like you are tightening the bolt in the tensioner, but really you are just moving the tensioner towards the engine which takes the tension off the belt. Once you get the tensioner as far over towards the engine as you could, keep it there and slide the belt off the alternator. You can then let the tensioner go back to its natural position and remove your ratchet and socket from the bolt. Remove the belt by taking it off all of the pulleys, be careful with the crank pulley, you may need to twist the belt a little to sneak it past the pulley and power steering rack.
Now is a good time to remove the A/C belt. Similar to the main belt there is a tensioner that needs to be moved toward the engine and downward. Only problem is there are a couple of lines in your way, so this is where the open end 15mm wrench comes in handy. Take the wrench and place it on the bolt of the tensioner and push her over and down (like tightening). The A/C belt is a bit of a pain. While holding the tensioner down slide the belt out from the idler pulley. You will still need to have the tension relieved to remove the belt, so keep the tension down yet. You can try to remove the belt from the compressor but I think there is still too much tension. You may need to sneak the belt off the tensioner while you have the wrench on it. Thats OK, just sneak the belt off and let it rest against your wrench and tensioner. Let up on the tensioner and release your wrench. You should be able to sneak the belt off the compressor and crank.
Check both belts thoroughly. Look for contamination and wear. Remember belts are made of rubber, rubber can squeal like a tire. If its worn and has little tread the belt can slip, like a tire in weather.
Now time to replace the idlers. Fairly easy really, just take your 15mm wrench or socket/ratchet and remove the bolts from both idlers. Be careful because there are washers that can fall and get lost. Once removed check where the washer rides on the engine and clean up any dirt and grease. Some new idlers have new washers. For the pre-00 Corvettes you should upgrade to the newer style washers/idler. Pop in the washers and pulleys and tighten the bolts. Don't need to be Hercules here, just snug it and give it one more snug for good luck.
Install the new belts, start with the A/C as it rides behind the main belt. This belt is a pain. In my opinion GM should have made it about a cm longer. It may be helpful to stretch the belt a bit. You can do this by placing the insides of your thumb against the inside of the belt and push outwards. Move the belt around and keep doing this. Push hard, they don't stretch easy. Another way is to use the handle of a vise or the bottom of your shoe and wrap one end of the belt around it. Pull the belt, but move the belt around so you don't oblong it. Start by installing it over the crank pulley and up and over the tensioner. Put your wrench on the tensioner and push it down. Now continue installing the belt by getting it over the compressor, make sure its lined up correctly especially on the part of the crank you cant see. Now is the time to be Hercules and push the belt down under the idler. Hopefully the belt is stretched enough to slip on.
The main belt is much easier and should not need to be stretched. Start by installing it around the crank pulley. Twist the belt to squeeze it between the power steering rack and the crank pulley. What I like to do is get the belt up and onto the tensioner. Now grab the belt on the drivers side where it comes out of the crank. Get it up and over the idler. Next is to get it under the power steering pulley and towards the alternator. The alternator will be the last pulley to install the belt onto. So go back to the tensioner and make sure the belt is on, slide the belt from the tensioner under the water pump pulley. Now you can take your ratchet/socket and relieve the tensioner. Grab the belt by the alternator and pull it tight. Make sure the belt is installed correctly around all of the pulleys other wise it may not make it around the alternator. Install it over the alternator.
Check the belts for proper alignment so it doesn't slip off. Once you are confident with the install, turn the engine on and visually check everything. Hopefully the squeals are gone! This is a good starting point if you cant determine the cause.
Hope this helps a bit guys. See ya!
Possible Causes: in order from most to least likely.
Belts Check the accessory and A/C belts. Dirty, cracked, worn, dry, misaligned... replace. For testing sake remove the main belt and run the engine for a quick minute. If noise is still there its in the A/C drive.
Idle Pulley The early C5's (97-00) had a poor designed idler pulley. It was thin and the washer behind it was flimsy. The washer would deflect and make contact with the pulley making a chirping noise. A stethoscope might help here.
Tensioners The C5 has 2 tensioners. One for the main belt the other for the A/C. Determine what system is making noise before replacing.
A/C Idler I have seen a few idlers in the A/C making noise. Pull the belts off and spin with your hand, if it squeals it should be replaced.
A/C Compressor Yup, I've seen the compressor squeal. Rare, but I have seen it and replaced it to cure the problem.
Alternator Alternators can squeal. Best way to test is to free wheel the pulley, if it squeals replace.
Water Pump, Crank pulley I have never seen the water pump or crank pulley cause a squeal. I wouldn't recommend replacing unless you know 100% that one is the cause. I'd suggest replacing other items prior.
Diagnostic Aid
Belt squeals can be difficult to diagnose. Especially when the squeal is only duplicated/present at a certain RPM/Load. Belts are very sensitive to contamination. Dirt, fluids and chemicals can make them squeal instantly. If there are any leaks from the engine -coolant, power steering, oil, etc... just a drop of fluid can make belts squeal. Also check for a leaking compressor, it can be easily missed. Usually the squeal will come back after replacing the belt if there are any leaks.
Start with visually checking the belt systems. Check the belt conditions and tension. If they check OK then start the engine and take another look. Have an assistant duplicate the squeal. Check for correct belt alignment, check for any pulleys wobbling. Note, the C5 crank pulley tends to wobble a little. If you can hear the squeal try using a stethoscope and listen to each pulley. Do Not place the stethoscope on any moving part. Place it on the bracket the pulley rides on. The squeal should be much more apparent near one pulley than the others while listening through the stethoscope.
Once you find the culprit, replace it. Even if the belt looks OK, if it has not been replaced recently now is the time to do it. Keep in mind the squeal noise might not be coming from just one pulley or belt. It could be from several pulleys or both belts. Sometimes you just cant pin-point the cause, so shooting parts at it is option. Personally I would replace both idler pulleys and both belts for starters. The idler pulleys and belts can be found at most auto parts stores. The pulleys run about $15-$20. The main belt will be around $50, and the A/C belt around $25. The Gatorback belt is good, if you can find one.
How To Replace Idler Pulleys and Belts
This is rather simple and can save you $$. Like I said, both pulley and both belts should run you about $100. One hour diag. plus parts and labor (at a dealer) you're looking at $300. So replacing the pulleys and belts should take you about one hour and will save you a couple hundred bucks.
Tools required: 3/8 Ratchet, 15mm Socket, 15mm Open End Wrench... That's it!
Start by removing the main belt. Take your ratchet with 15mm socket and turn the tensioner towards the engine. Basically you act like you are tightening the bolt in the tensioner, but really you are just moving the tensioner towards the engine which takes the tension off the belt. Once you get the tensioner as far over towards the engine as you could, keep it there and slide the belt off the alternator. You can then let the tensioner go back to its natural position and remove your ratchet and socket from the bolt. Remove the belt by taking it off all of the pulleys, be careful with the crank pulley, you may need to twist the belt a little to sneak it past the pulley and power steering rack.
Now is a good time to remove the A/C belt. Similar to the main belt there is a tensioner that needs to be moved toward the engine and downward. Only problem is there are a couple of lines in your way, so this is where the open end 15mm wrench comes in handy. Take the wrench and place it on the bolt of the tensioner and push her over and down (like tightening). The A/C belt is a bit of a pain. While holding the tensioner down slide the belt out from the idler pulley. You will still need to have the tension relieved to remove the belt, so keep the tension down yet. You can try to remove the belt from the compressor but I think there is still too much tension. You may need to sneak the belt off the tensioner while you have the wrench on it. Thats OK, just sneak the belt off and let it rest against your wrench and tensioner. Let up on the tensioner and release your wrench. You should be able to sneak the belt off the compressor and crank.
Check both belts thoroughly. Look for contamination and wear. Remember belts are made of rubber, rubber can squeal like a tire. If its worn and has little tread the belt can slip, like a tire in weather.
Now time to replace the idlers. Fairly easy really, just take your 15mm wrench or socket/ratchet and remove the bolts from both idlers. Be careful because there are washers that can fall and get lost. Once removed check where the washer rides on the engine and clean up any dirt and grease. Some new idlers have new washers. For the pre-00 Corvettes you should upgrade to the newer style washers/idler. Pop in the washers and pulleys and tighten the bolts. Don't need to be Hercules here, just snug it and give it one more snug for good luck.
Install the new belts, start with the A/C as it rides behind the main belt. This belt is a pain. In my opinion GM should have made it about a cm longer. It may be helpful to stretch the belt a bit. You can do this by placing the insides of your thumb against the inside of the belt and push outwards. Move the belt around and keep doing this. Push hard, they don't stretch easy. Another way is to use the handle of a vise or the bottom of your shoe and wrap one end of the belt around it. Pull the belt, but move the belt around so you don't oblong it. Start by installing it over the crank pulley and up and over the tensioner. Put your wrench on the tensioner and push it down. Now continue installing the belt by getting it over the compressor, make sure its lined up correctly especially on the part of the crank you cant see. Now is the time to be Hercules and push the belt down under the idler. Hopefully the belt is stretched enough to slip on.
The main belt is much easier and should not need to be stretched. Start by installing it around the crank pulley. Twist the belt to squeeze it between the power steering rack and the crank pulley. What I like to do is get the belt up and onto the tensioner. Now grab the belt on the drivers side where it comes out of the crank. Get it up and over the idler. Next is to get it under the power steering pulley and towards the alternator. The alternator will be the last pulley to install the belt onto. So go back to the tensioner and make sure the belt is on, slide the belt from the tensioner under the water pump pulley. Now you can take your ratchet/socket and relieve the tensioner. Grab the belt by the alternator and pull it tight. Make sure the belt is installed correctly around all of the pulleys other wise it may not make it around the alternator. Install it over the alternator.
Check the belts for proper alignment so it doesn't slip off. Once you are confident with the install, turn the engine on and visually check everything. Hopefully the squeals are gone! This is a good starting point if you cant determine the cause.
Hope this helps a bit guys. See ya!
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11-15-2010, 10:23 AM
#11
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Don't replace idler pulleys right away...
because they come off easily and aren't always bad. I've done this on several cars with great results. Just remove the grease seal on the bearing with a small pick or just your fingernail. You'll probably find a dry bearing with only traces of the long lost grease. Wash it out, lightly
pack it with a good grease, snap the seal back in and reassemble. So simple a caveman could do it
and would make a good project for those wanting to learn to do more work on their cars.
pack it with a good grease, snap the seal back in and reassemble. So simple a caveman could do it
and would make a good project for those wanting to learn to do more work on their cars.
11-15-2010, 10:34 AM
#12
Race Director
Chirp seems to be getting progressively worse with the colder weather. As a last resort, sprayed silicone on the main belt yesterday which stopped the chirp instantly. Not expecting long term resolution but it seems to have isolated the problem. Also noticed a slight wobble to the harmonic balancey pulley with engine idling.
11-15-2010, 11:54 AM
#13
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Chirp seems to be getting progressively worse with the colder weather. As a last resort, sprayed silicone on the main belt yesterday which stopped the chirp instantly. Not expecting long term resolution but it seems to have isolated the problem. Also noticed a slight wobble to the harmonic balancey pulley with engine idling.
11-15-2010, 12:11 PM
#14
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Guys, I have belt squeek only when the A/C is OFF. When I turn it on and I hear the A/C kick on the squeek instantly goes away. What could it be? The belts and idler pulles are all brand new? Tensioner?
11-15-2010, 01:30 PM
#15
Melting Slicks
Probably something in the A/C belt system. The load of the compressor is enough to dampen the squeal. Take the belt off and spin the tensioner and idler pulleys. See if one makes any noise or does not spin smoothly. Check the belt its self. Id say its either the tensioner or compressor if the other items are new.
11-16-2010, 10:25 PM
#16
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My idler pulley had little pieces of rubber, I'm assuming from the belt, stuck to the surface. I cleaned the pieces off using scotchbrite and have not had any noise since.
11-16-2010, 11:42 PM
#17
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The tensioner shouldn't be moving like that. The belt system should run very smoothly.
Look at the gap between the clutch plate and the pulley. The plate might not be pulling back from the pulley and dragging. Mine was making noise and I pulled the clutch plate out a little more so it would not drag.
Peter
Peter
11-17-2010, 08:52 PM
#18
Burning Brakes
Had this problem recently, and I swear by the Gatorback belts. However, as it turned out, the water pump was dripping a bit, enough to mess up the relatively new a.c. belt! Lucky for me I have an extended warranty, and my local dealer took car of the water pump and belt for me.
01-22-2013, 10:41 PM
#19
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C5 Z06 idler pulley/tensioner/main belt squeak
If you have the Squeak, buy the A/C belt and the main drive belt and replace both. While you are there get all four pulleys and replace them also. The two on the A/C drive side are the same part number for the tensioner and idler.
All work can be done from the top side without getting under the car.
A small 3/8 breaker bar and a 15mm socket is all that is needed, to move the tensioner and also to take off the bolts holding the Idlers and the tensioner pulleys.
Job is not bad and takes about an hour with a helper.
Dayco Part Numbers
89135 - A/C pulleys you need 2 of them
89059 - Main Idler
89015 - Main Tensioner
All work can be done from the top side without getting under the car.
A small 3/8 breaker bar and a 15mm socket is all that is needed, to move the tensioner and also to take off the bolts holding the Idlers and the tensioner pulleys.
Job is not bad and takes about an hour with a helper.
Dayco Part Numbers
89135 - A/C pulleys you need 2 of them
89059 - Main Idler
89015 - Main Tensioner
