Easy A/C belt replacement?
Team Owner
Joined: May 2006
Posts: 21,473
Likes: 356
From: Palmdale, Ca----- 2009 Cyber Gray 4LT A6 F55 452 RWHP 422 RWTQ- RIP 1998 C5 734 RWHP & 585 RWTQ-----
Purchase a long 15 mm wrench in order to grab the nut on the tensioner and be patient and you'll be done in no time!
I got my long handled 15mm wrench from Autozone
Thanks,Matt
I got my long handled 15mm wrench from Autozone
Thanks,Matt
Racer
Joined: Nov 2012
Posts: 376
Likes: 21
From: Coos Bay Oregon
Wow! I feel pretty good about my mechanic skills now. I've changed my AC belt a couple of times now and it really hasn't been a problem. I do it from the top. I put the belt around the crankshaft pulley and lay it close to where I want it. I put the belt over the tensioner pulley first and then go to the AC pulley and do the upper idler pulley last. It's just easier for me to do that one handed. If you can get someone to hold the wrench the rest of it would be easier. They would have to do it from the driver's side of the car because of the lack of room.
Melting Slicks
Joined: Oct 2005
Posts: 2,989
Likes: 352
From: Carson City Nevada
Intermediate
Joined: Oct 2018
Posts: 37
Likes: 3
From: MA.
Like your post. The YouTube videos leave out the final details of putting the air conditioning belt on.
Have a 1998 C5 6 speed and was time to replace tensioners, belts and idler pulleys. Double checked
idler parts diameter, all correct. Small, A/C belt kept getting hung up in back of main shaft. Always
looking for more belt slack.
Gonna give it one more try with a 15mm flex head wrench.
Your post has given me hope. Know it's tougher with an automatic.
Serpentine belt is now very easy now because I have been running the
car without air conditioning.
Have spent at least 10 hours to get this small belt on.
Have a 1998 C5 6 speed and was time to replace tensioners, belts and idler pulleys. Double checked
idler parts diameter, all correct. Small, A/C belt kept getting hung up in back of main shaft. Always
looking for more belt slack.
Gonna give it one more try with a 15mm flex head wrench.
Your post has given me hope. Know it's tougher with an automatic.
Serpentine belt is now very easy now because I have been running the
car without air conditioning.
Have spent at least 10 hours to get this small belt on.
Intermediate
Joined: Oct 2018
Posts: 37
Likes: 3
From: MA.
C5 ac belt
Ya. Consider your post encouragement.
Found good info on the Corvette Forum. Will tell my son to help me. It’s really a one person job.😎 The best post disappeared, but took a picture of it thank goodness.
A good friend, restoring a 1958 Cadillac, his sixth vehicle project, came by to see my Corvette. Started it up, he heard a chirp while it warmed up. I changed the main automatic belt tensioner. The chirp went away and decided to replace the complete 2 belt system. 23 year old car. At 73 I have persevered.
Found good info on the Corvette Forum. Will tell my son to help me. It’s really a one person job.😎 The best post disappeared, but took a picture of it thank goodness.
A good friend, restoring a 1958 Cadillac, his sixth vehicle project, came by to see my Corvette. Started it up, he heard a chirp while it warmed up. I changed the main automatic belt tensioner. The chirp went away and decided to replace the complete 2 belt system. 23 year old car. At 73 I have persevered.
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Brett Foote
Running Guns & Moonshine
Joined: Aug 2001
Posts: 12,593
Likes: 7,257
From: CT
I mean, if you have no jack you can find a spot to drive up on a hill or angle so you can shimmy under the car. Get the sero belt off from above first via the tensioner. Then shimmy under, do same for ac and swap new in, realign the sero belt, then reconnect on top. Maybe a ten or fifteen minute operation from the time you park to the time you close the hood again. What's the bolt size on the tensioner.... 15mm? 3/4?
Intermediate
Joined: Feb 2005
Posts: 32
Likes: 3
From: Las Vegas NV
I found this write up either on this forum or another one about 8 years ago and used it when I changed both belts on my 98 A4.
If I recall, it was pain in the backside, but doable.
---------------------------------------
I have an A4 which seems to have a different setup than the M6. The only real difference is the cooling lines that cross infront of the a/c tension pully. I used a 15 MM socket to do all of the work. I also did everything from the top of the motor. You will need an offset socket handle to deal with the a/c belt. A regular socket wrench hits the water pump pulley so you need a flexible wrench.
The first step is to remove the large serpentine belt this is pretty straight forward. Simply put the socket wrench on the belt tension pulley located on the passenger side at the top of the motor. Push the wrench towards the drivers side of the motor and the belt will slip off pretty easy. Remove the belt from the motor. I have a 2000 which has a large ABS pump so I had to do some twisting of the belt to get it out from between the power steering pulley and the abs pump.
With that out of the way it is time to tackle the a/c belt. The belt runs from the a/c compressor and the drive shaft pulley and is squeezed tight between two pulley's. The lower pulley is the one that needs to be moved to relieve the tension.
On mine there are two steel cooling lines that cross right in front of the tension pulley bolt. There is a clip holds the two lines together. I popped the clip off one of the lines and was able to spread them apart enough to get the socket onto the bold. I had to put the socket on the bolt first and then insert the handle.
This is where you need to use the offset handle. Put the handle on and push the wrench towards the drivers side. The tension will relieve and you will be able to slip the belt off with relative ease. (the keyword being relative).
Ok that's the easy part. at the point you should have all the belts off.
At this point I took a wire brush and cleaned all the pulleys. This seems to be one of the key reasons why belts squeal. GM also advises against belt dressing. So I didn't use any.
Putting the a/c belt on is where the challenge came.
Slip the a/c belt onto the drive shaft pulley first. I then put the belt OVER the tensioner pulley. I also put the belt OVER the upper guide pulley. this allowed enough tension for me to slip the belt over the ac compressor.
Now after much trial and error I learned that it was smart to close my eyes and use my fingers to follow the path of the belt and make sure that it is on the drive shaft pulley all the way around. There is NO room for error. If it is off by the smallest amount the rest of this project is a nightmare.
Once you are sure that the belt is on its track it's time to reattach the socket and handle. Relieve the tension again and start to work the belt under the upper pulley. To visualize this the belt will be in an hourglass shape as it follows its path. This is where I had my biggest problem. I thought I had pushed the tensioner as far as it would go, but I still couldn't get enough slack to slip the upper part of the belt into place. Finally I pushed just a little further. The belt slipped into place and that was all she wrote. Once you are happy with the position of the belt. I would start the engine briefly and check to make sure the belt is tracking properly.
Then be sure to put the coolant lines back together and replace the clip so that they are back the way they were from the start.
Next it is time to put the serpentine belt back in place. Start at the alternator and then over the power steering pump etc. Finally back to the upper tensioner. Relieve the tension as before and slip the new belt into place.
That's it. Start it up and you are done. I have attached a picture of the belt path just in case you don't have one. I hope this helps. If you have any questions please feel free to PM me or post here. I am happy to help.
If I recall, it was pain in the backside, but doable.
---------------------------------------
I have an A4 which seems to have a different setup than the M6. The only real difference is the cooling lines that cross infront of the a/c tension pully. I used a 15 MM socket to do all of the work. I also did everything from the top of the motor. You will need an offset socket handle to deal with the a/c belt. A regular socket wrench hits the water pump pulley so you need a flexible wrench.
The first step is to remove the large serpentine belt this is pretty straight forward. Simply put the socket wrench on the belt tension pulley located on the passenger side at the top of the motor. Push the wrench towards the drivers side of the motor and the belt will slip off pretty easy. Remove the belt from the motor. I have a 2000 which has a large ABS pump so I had to do some twisting of the belt to get it out from between the power steering pulley and the abs pump.
With that out of the way it is time to tackle the a/c belt. The belt runs from the a/c compressor and the drive shaft pulley and is squeezed tight between two pulley's. The lower pulley is the one that needs to be moved to relieve the tension.
On mine there are two steel cooling lines that cross right in front of the tension pulley bolt. There is a clip holds the two lines together. I popped the clip off one of the lines and was able to spread them apart enough to get the socket onto the bold. I had to put the socket on the bolt first and then insert the handle.
This is where you need to use the offset handle. Put the handle on and push the wrench towards the drivers side. The tension will relieve and you will be able to slip the belt off with relative ease. (the keyword being relative).
Ok that's the easy part. at the point you should have all the belts off.
At this point I took a wire brush and cleaned all the pulleys. This seems to be one of the key reasons why belts squeal. GM also advises against belt dressing. So I didn't use any.
Putting the a/c belt on is where the challenge came.
Slip the a/c belt onto the drive shaft pulley first. I then put the belt OVER the tensioner pulley. I also put the belt OVER the upper guide pulley. this allowed enough tension for me to slip the belt over the ac compressor.
Now after much trial and error I learned that it was smart to close my eyes and use my fingers to follow the path of the belt and make sure that it is on the drive shaft pulley all the way around. There is NO room for error. If it is off by the smallest amount the rest of this project is a nightmare.
Once you are sure that the belt is on its track it's time to reattach the socket and handle. Relieve the tension again and start to work the belt under the upper pulley. To visualize this the belt will be in an hourglass shape as it follows its path. This is where I had my biggest problem. I thought I had pushed the tensioner as far as it would go, but I still couldn't get enough slack to slip the upper part of the belt into place. Finally I pushed just a little further. The belt slipped into place and that was all she wrote. Once you are happy with the position of the belt. I would start the engine briefly and check to make sure the belt is tracking properly.
Then be sure to put the coolant lines back together and replace the clip so that they are back the way they were from the start.
Next it is time to put the serpentine belt back in place. Start at the alternator and then over the power steering pump etc. Finally back to the upper tensioner. Relieve the tension as before and slip the new belt into place.
That's it. Start it up and you are done. I have attached a picture of the belt path just in case you don't have one. I hope this helps. If you have any questions please feel free to PM me or post here. I am happy to help.
Intermediate
Joined: Oct 2018
Posts: 37
Likes: 3
From: MA.
Safety First -No Shimmy under C5
I mean, if you have no jack you can find a spot to drive up on a hill or angle so you can shimmy under the car. Get the sero belt off from above first via the tensioner. Then shimmy under, do same for ac and swap new in, realign the sero belt, then reconnect on top. Maybe a ten or fifteen minute operation from the time you park to the time you close the hood again. What's the bolt size on the tensioner.... 15mm? 3/4?
secondary support. I had success installing both belts, both tensioners and idler pulleys today. The trick was putting 3 pieces of
duct tape to hold the A/C belt in place in the four grove pulley on the harmonic balancer while I assembled the
rest from the top. Found this idea on Corvette Forum years ago and cannot find the thread to give him credit.
Know he drank a beer to celebrate getting the A/C belt on and reminded members to remove the tape before
installing the Main serpentine belt. That was a breeze for me. Stay safe.
Last edited by Rocky48; Sep 8, 2021 at 05:31 PM. Reason: Missed word
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Moving this over to C5 Tech.
Race Director
Joined: Oct 2004
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Melting Slicks
Joined: Mar 1999
Posts: 3,211
Likes: 167
From: Rochester Hills Michigan
The stupid aluminum lines fight you the whole way trying to get the belt off and on along with tensioner. I did a lot from the top just working blindly with hands. I manage to get a long socket adapter for the tensioner pulley bolt and if you just lift the front end a bit ( not off ground) you can snake your socket end in after just starting the bolt fingered in a bit.
Race Director
Joined: Oct 2004
Posts: 12,864
Likes: 4,666
The stupid aluminum lines fight you the whole way trying to get the belt off and on along with tensioner. I did a lot from the top just working blindly with hands. I manage to get a long socket adapter for the tensioner pulley bolt and if you just lift the front end a bit ( not off ground) you can snake your socket end in after just starting the bolt fingered in a bit.
Last edited by grinder11; Sep 10, 2021 at 02:30 PM.