A/C sqeeeel - HELP! - The 1947 - Present Chevrolet & GMC Truck Message Board Network

jones · 07-10-2002, 03:00 PM

the question:
my belts squeel bad whenever the AC is off. how can I fix this??
please, oh please forward your ideas. ;-0

the background: it's an 86 K20 that I converted from a 350 to a 402. I bought all new OEM accessories to fit the big block like brackets, PS pump, AC compressor & hoses, and pulleys.
whenever the AC belt is on and the compressor is engaged, things are quiet. but when I turn off the air the squeel is loud & embarassing.

what I've done:
replaced the already new pulleys (in case one was warped or bent from the factory)
replaced the belts, with both the same and different brands.
cleaned the pulleys & belts with brake cleaner.
used candle wax on the belts to quiet them down (an old-timer trick that didn't work)

so I either run with the air on all the time, or run without the belt.
I wonder if the fact that the alternator uses a sepantine belt, while the PS & AC use 'V' belts could have something to do with it? maybe I should replace the pulleys on the alt., h2o pump, and crank with older ones that use a v-belt for the alt. ideas??

thanks in advance!

jones · 07-11-2002, 08:30 PM

well I sure thought a squeeling belt wasn't that unusual.

anybody got an idea for me?

also wondering what kind of vent temps a good AC system puts out?

gchemist · 07-12-2002, 09:02 AM

Does the A/C clutch disengage properly? Remove the belt and see if you can turn the outter pulley by hand. If not the clutch on the compressor is bad. What type of belt are you using? Smooth or ribbed on the side that rides in the groove? Try using belts from Oreilleys. How far down does the belt ride? The belt may just be expanding too.

Brake cleaner?

Take some sand paper and run it through the groves. Use a very harsh grit. You some something that will grab the belt.

One final thought:

I'm doing the conversion mine. You have to relocate the A/C compressor and the alternator. Change the water pump to a reverse rotation type. Add a pulley to the crank, water pump and the power steering pump. I don't like the smog pump option so a find a setup with out one. Complete systems can be found on www.ebaymotors.com
Here is a website where you can buy an entire used system for $200.00
http://www.tacreationsusa.com/bracke...ccessories.htm

gchemist · 07-12-2002, 09:04 AM

My A/C converted to R134 cools at less than 40 degrees!!

jones · 07-12-2002, 11:05 AM

thanks gchemist,

the compressor engages OK and the belt is a regular old v-belt. only tha alt-h2o pump- crank belt is the grooved sepentine kind.

I'll get a pic up here later today.

thanks again for sharing some brain cells.
J

jones · 07-12-2002, 03:43 PM

here's what I mean. the alt belt is a groove belt while the others are v belts.
anyone getting belt noise with this combo?

07-10-2002, 03:00 PM	#1
jones Registered User Join Date: Jun 2002 Location: North Idaho Posts: 43	A/C sqeeeel - HELP! the question: my belts squeel bad whenever the AC is off. how can I fix this?? please, oh please forward your ideas. ;-0 the background: it's an 86 K20 that I converted from a 350 to a 402. I bought all new OEM accessories to fit the big block like brackets, PS pump, AC compressor & hoses, and pulleys. whenever the AC belt is on and the compressor is engaged, things are quiet. but when I turn off the air the squeel is loud & embarassing. what I've done: replaced the already new pulleys (in case one was warped or bent from the factory) replaced the belts, with both the same and different brands. cleaned the pulleys & belts with brake cleaner. used candle wax on the belts to quiet them down (an old-timer trick that didn't work) so I either run with the air on all the time, or run without the belt. I wonder if the fact that the alternator uses a sepantine belt, while the PS & AC use 'V' belts could have something to do with it? maybe I should replace the pulleys on the alt., h2o pump, and crank with older ones that use a v-belt for the alt. ideas?? thanks in advance!

07-12-2002, 09:02 AM	#3
gchemist BAD BOW-Silverado XST Join Date: May 2000 Location: Senior Member from Austin, TX Posts: 6,431	Does the A/C clutch disengage properly? Remove the belt and see if you can turn the outter pulley by hand. If not the clutch on the compressor is bad. What type of belt are you using? Smooth or ribbed on the side that rides in the groove? Try using belts from Oreilleys. How far down does the belt ride? The belt may just be expanding too. Brake cleaner? Take some sand paper and run it through the groves. Use a very harsh grit. You some something that will grab the belt. One final thought: I'm doing the conversion mine. You have to relocate the A/C compressor and the alternator. Change the water pump to a reverse rotation type. Add a pulley to the crank, water pump and the power steering pump. I don't like the smog pump option so a find a setup with out one. Complete systems can be found on www.ebaymotors.com Here is a website where you can buy an entire used system for $200.00 http://www.tacreationsusa.com/bracke...ccessories.htm __________________ Gerardo a.k.a. Mad Chemist Silverado XST videos

07-12-2002, 09:04 AM	#4
gchemist BAD BOW-Silverado XST Join Date: May 2000 Location: Senior Member from Austin, TX Posts: 6,431	My A/C converted to R134 cools at less than 40 degrees!! __________________ Gerardo a.k.a. Mad Chemist Silverado XST videos

07-12-2002, 03:43 PM	#6
jones Registered User Join Date: Jun 2002 Location: North Idaho Posts: 43	here's what I mean. the alt belt is a groove belt while the others are v belts. anyone getting belt noise with this combo? Attached Images __________________ 69 C15 86 K20

07-11-2002, 08:30 PM	#2
jones Registered User Join Date: Jun 2002 Location: North Idaho Posts: 43	well I sure thought a squeeling belt wasn't that unusual. anybody got an idea for me? also wondering what kind of vent temps a good AC system puts out?

07-12-2002, 11:05 AM	#5
jones Registered User Join Date: Jun 2002 Location: North Idaho Posts: 43	thanks gchemist, the compressor engages OK and the belt is a regular old v-belt. only tha alt-h2o pump- crank belt is the grooved sepentine kind. I'll get a pic up here later today. thanks again for sharing some brain cells. J



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