Alternator Belt Squeal - Team Camaro Tech
Tech 2000 Our previous General Forum
Replies ONLY - no new topics.

LinkBack Thread Tools Display Modes
post #1 of 13 (permalink) Old Jul 23rd, 01, 02:42 AM Thread Starter
Senior Tech
Join Date: Sep 1999
Location: Salisbury,MD,USA
Posts: 111

Looking for some help on this issue. I just got the 350 back in the car and probably have 70 miles on it. Engine runs strong, but the alternator belt wants to squeal when I rev the engine quickly either from within the car or by hand operating the throttle. If I bring up the RPM's smoothly it does not happen, but thats no fun. Here's what I have done to no avail:
1. Tightned and loosened the belt, and put a little soap on the alt. belt.
2. Took off alt. belt, started car, no squeal when revved.
3. Thought that belt might be new and need some wear on the edges, so I took and roughened the belt slightly, still squeals.
4. I painted the belt grooves, so I took sandpaper and roughened the grooves thinking this would allow the belt to "catch" and again nothing.
I'm looking for help on this nagging issue, any thoughts would be appreciated. Thanks in advance.
Barry H is offline  
Sponsored Links
post #2 of 13 (permalink) Old Jul 23rd, 01, 04:31 AM
Senior Tech
Join Date: Jan 2000
Location: Houston, TX USA
Posts: 797

I hate to over-simplify but are you absolutely certain that you are attempting to use the right belt for your application? Don't trust the parts guy behind the counter-look up that part number and verify that you do in fact have the right belt as they vary in width. If you are running a belt that is too narrow there is nothing you can do to stop the squealing..
Go69 is offline  
post #3 of 13 (permalink) Old Jul 23rd, 01, 04:39 AM Thread Starter
Senior Tech
Join Date: Sep 1999
Location: Salisbury,MD,USA
Posts: 111

Thanks for the reply. I'm using the same type alternator belt as in the past, but I did increase the length slightly. It looks to fit very well, but it does have the "teeth" (for the lack of a better term)not a solid "V" shape. Thanks.
Barry H is offline  
post #4 of 13 (permalink) Old Jul 23rd, 01, 05:38 AM
Senior Tech
Join Date: May 2001
Location: Michigan
Posts: 2,920

Did you replace the water pump when you had the engine out? The reason I'm asking is with several manufacturers and remanufacturers there are sometimes slight variances in the lengths of the pumps. I don't mean short vs long pumps, but variances between two pumps that are suppose to be the same length. This will cause your belt to be out of line with the other pulleys slightly and the alternator is usually the longest run on the belt. They make spacer kits to correctly set the water pump pulley back in line. The notched belt will actually run cooler and was a good choice, I don't think that's your problem. Again make sure your belt width is correct for the depth pulleys you have. Sounds like you've already tried the other things, have you tried another alternator? The rear bearings will fail in a lot of the new ones and can make a sound that is similar to a belt. But usually if it's a bearing it will be there all the time, not just when you rev the engine quickly.
SY1 is offline  
post #5 of 13 (permalink) Old Jul 23rd, 01, 05:50 AM Thread Starter
Senior Tech
Join Date: Sep 1999
Location: Salisbury,MD,USA
Posts: 111


Thanks for the response. The water pump was replaced during the rebuild and everything seems to be lined up properly. I will double check the belt width versus the belt that I have versus what the parts store says I should have for a 67 350. Maybe there was a slight difference when I went with the longer belt, but I took the old one in and asked for the same belt only longer. Again thanks for the responses.
Barry H is offline  
post #6 of 13 (permalink) Old Jul 23rd, 01, 06:23 AM
Super Moderator
Bess-68's rule
Everett#2390's Avatar
Join Date: Sep 2000
Location: Va Beach VA
Posts: 31,940

Take and spray WD-40 on belt.

Does it quiet down? If so, then tighten belt alittle more. Also, another item to check is alternator output(amps), is there a load on it for some mysterious reason?

I adjust for 3/8-1/2 in deflection on the longest leg of belt.

Everett#2390 is offline  
post #7 of 13 (permalink) Old Jul 23rd, 01, 07:31 AM
Senior Tech
Join Date: Jan 2001
Location: Benicia CA
Posts: 1,293

You might try switching to a Dayco "Top Cog" belt. The "teeth" are on the outside which seems to let the belt flex into the grooves better.
Worked on my 69.


69 SS396 Resti-Clone
WCA Member
[email protected]
69 Pics
Joe G is offline  
post #8 of 13 (permalink) Old Jul 23rd, 01, 07:54 AM
Senior Tech
Join Date: May 2001
Location: Michigan
Posts: 2,920

If you need to shim you water pump pulley Mr. Gasket makes water pump and crank pulley shim kits that include shims of various thicknesses. Edelbrock, Stewart, Moroso and Weiand pumps are usually very close to stock. But many of the less expensive rebuilt pumps will be off a little.
SY1 is offline  
post #9 of 13 (permalink) Old Jul 24th, 01, 04:48 PM
Join Date: Apr 2001
Location: green bay wi
Posts: 14

Do You have a repro alt. bracket? Mine did and that was why mine squealed because the bend in the repro was not quite exact as the orig. Changed to orig and belts lined up perfect,end of squeals.
camarko is offline  
post #10 of 13 (permalink) Old Jul 24th, 01, 11:06 PM
Senior Tech
Join Date: May 2001
Location: NZ
Posts: 106

I have a double pulley on my alternator and run two belts - no squeeling even without running them very tight - might be worth a try if all else fails and you don't have other accessories which prevent this

68 SS
BrianW is offline  
post #11 of 13 (permalink) Old Jul 25th, 01, 06:14 AM
Gold Lifetime Member
Join Date: Feb 2000
Location: Accord, NY
Posts: 4,817

Take a metal straight edge and lay it across the two pulleys. You'll be able to see if they're in alignment. Does the belt show any shininess on one edge? I'm not a big fan of the inside toothed belts.

Rick Dorion
69 RS Conv,355,M20,4.10's
RickD is offline  
post #12 of 13 (permalink) Old Jul 25th, 01, 07:03 AM
Join Date: Dec 2000
Location: Jacksonville, FL, United States
Posts: 16

It may be a the wrong series belt. I had th esame problem on mine. I had a 13 series and it wouldn't stop sqeuealing. I switched to a 15 series and it went away.
kleen2000 is offline  
post #13 of 13 (permalink) Old Jul 25th, 01, 07:08 AM
David Pozzi
davidpozzi's Avatar
Join Date: Nov 1999
Location: Central California, USA
Posts: 10,109

If you have a heavy or large fan, that could be what is doing it, not the alternator.
What year camaro?
Don't ever spray any lubricant on the belt, you don't want the belt to be slippery.
You can test which belt is squeaking by spraying a little water on the belt.
Water will make the belt more squeaky for a half hour or so.
Painting the pulley won't be a permanent fix as the paint will wear off.
Try a different brand of belt.
I like the Gates belts best.

Check my web page for First Gen Camaro suspension info:
David's Motorsports page
First Gen Suspension Page
67 RS 327
69 Camaro Vintage Racer
65 Lola T-70 Chev 350 Can-Am Vintage Racer
davidpozzi is offline  
Sponsored Links

Quick Reply

Register Now

In order to be able to post messages on the Team Camaro Tech forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address.
NOTE we receive a lot of registrations with bad email addresses. IF you do not receive your confirmation email you will not be able to post. contact support and we will try and help.
Be sure you enter a valid email address and check your spam folder as well.

Email Address:


Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Posting Rules  
You may not post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome