Serpentine belt squeal issue A/C compressor - The 1947 - Present Chevrolet & GMC Truck Message Board Network

GMC87 · 10-10-2010, 11:05 PM

So my serpentine has been squealing on my 87 (454). After replacing the belt checking the tensioner I found out today that it is actually the A/C compressor pulley will lock up when I turn the heater on????????

Am I missing something here why does the heat effect the A/C compressor?

And is there any way to rebuild the pulley?

I assume there is a clutch of some sort in it.

When the heat is off it spins just fine no squeal as soon as I turn the heat on I can see the pulley stops and belt is just sliding over it. The belt is new and as tight as it can get.

Any suggestions??????????????

CaliDude76 · 10-10-2010, 11:19 PM

Sounds like you might be having an issue with the HVAC Control head itself... are you sure your not putting it in defrost mode?.. that does activate the compressor as well...

.. does your compressor normally work otherwise...?? if you turn the actual A/C on..? sounds as if your compressor is seized completely... and somehow getting activated by the HVAC head unit....when in heat mode

If you haven't already... and I could be preaching to the choir here... but just unplug the compressor....

GMC87 · 10-10-2010, 11:24 PM

It will squeal in A/C and in defrost.

If I can just up plug it for now that would be fine, I can address a proper fix next summer when I need it.

CaliDude76 · 10-10-2010, 11:28 PM

Quote:

Originally Posted by GMC87

It will squeal in A/C and in defrost.

..Yeah, that might be your best bet.... it does sound like your compressor is seized.... the plug is usually located right at the front of the compressor between the pulley and the body of the compressor.... should have no problem disconnecting.... good luck!

87chevy.com · 10-10-2010, 11:32 PM

the a/c is supposed to run in defrost for sure, not sure about heat though.... I will start the truck up tomarrow and see what my truck does when I turn on the heat.
Clint

GMC87 · 10-11-2010, 08:37 AM

I unplugged it this morning on the way to work, no squeal.

Looks like I will leave it that way for the winter and deal with it in the spring.

Thanks of the replies.

Slonaker · 10-11-2010, 12:45 PM

On my '86 I was having problems with the compressor clutch engaging when I had it on "vent." Later it was engaging on all settings except "off." I recently replaced the dash control, and that fixed all of those issues.

It sounds like you need a new dash control and a new compressor.

Slonaker

CaliDude76 · 10-11-2010, 08:15 PM

^^ x2

10-10-2010, 11:05 PM	#1
GMC87 Registered User Join Date: Aug 2010 Location: N.Canton, Ohio Posts: 70	Serpentine belt squeal issue A/C compressor So my serpentine has been squealing on my 87 (454). After replacing the belt checking the tensioner I found out today that it is actually the A/C compressor pulley will lock up when I turn the heater on???????? Am I missing something here why does the heat effect the A/C compressor? And is there any way to rebuild the pulley? I assume there is a clutch of some sort in it. When the heat is off it spins just fine no squeal as soon as I turn the heat on I can see the pulley stops and belt is just sliding over it. The belt is new and as tight as it can get. Any suggestions??????????????

10-10-2010, 11:19 PM	#2
CaliDude76 All About the BOWTIE Join Date: May 2010 Location: Los Banos, California Posts: 436	Re: Serpentine belt squeal issue A/C compressor Sounds like you might be having an issue with the HVAC Control head itself... are you sure your not putting it in defrost mode?.. that does activate the compressor as well... .. does your compressor normally work otherwise...?? if you turn the actual A/C on..? sounds as if your compressor is seized completely... and somehow getting activated by the HVAC head unit....when in heat mode If you haven't already... and I could be preaching to the choir here... but just unplug the compressor.... __________________ CaliDude76 "... Being "SQUARE".. is where it's at...." Proverbs 15:30 .... "A Cheerful look brings joy to the heart, and good news gives health to the bones..." Be exceedingly blessed today, my friends!... Last edited by CaliDude76; 10-10-2010 at 11:20 PM.

10-10-2010, 11:24 PM	#3
GMC87 Registered User Join Date: Aug 2010 Location: N.Canton, Ohio Posts: 70	Re: Serpentine belt squeal issue A/C compressor It will squeal in A/C and in defrost. If I can just up plug it for now that would be fine, I can address a proper fix next summer when I need it.

10-10-2010, 11:32 PM	#5
87chevy.com BMW & ASE Master Certified Join Date: Feb 2004 Location: Houston, Texas Posts: 1,266	Re: Serpentine belt squeal issue A/C compressor the a/c is supposed to run in defrost for sure, not sure about heat though.... I will start the truck up tomarrow and see what my truck does when I turn on the heat. Clint __________________ 1987 Silverado - L83 5.3 w/ 6L80e ,A/C,P/W,P/L,TILT, HID projectors, Wilwood C-10 Pro Spindles w/ 2018 silverado front brakes & C-5 Corvette Rear Disc Brakes 1999 BMW 528i - 5.7 LS1 w/ 4l60e, Ford 8.8 IRS w31 spline posi & FX-r projector retrofit New project: 2006 BMW x5 6cyl AWD to L83 6l80e 4wd to 2WD / RWD A poor man buy's it twice finally got my domain name back, 87chevy.com.... site rework in progress

10-11-2010, 08:37 AM	#6
GMC87 Registered User Join Date: Aug 2010 Location: N.Canton, Ohio Posts: 70	Re: Serpentine belt squeal issue A/C compressor I unplugged it this morning on the way to work, no squeal. Looks like I will leave it that way for the winter and deal with it in the spring. Thanks of the replies.

10-11-2010, 12:45 PM	#7
Slonaker Insert Witty Text Here Join Date: Oct 2002 Location: San Antonio, TX Posts: 3,415	Re: Serpentine belt squeal issue A/C compressor On my '86 I was having problems with the compressor clutch engaging when I had it on "vent." Later it was engaging on all settings except "off." I recently replaced the dash control, and that fixed all of those issues. It sounds like you need a new dash control and a new compressor. Slonaker __________________ '86 Chevy C10 (Sold 04/19/13 ) Stock '01 Silverado

10-11-2010, 08:15 PM	#8
CaliDude76 All About the BOWTIE Join Date: May 2010 Location: Los Banos, California Posts: 436	Re: Serpentine belt squeal issue A/C compressor ^^ x2 __________________ CaliDude76 "... Being "SQUARE".. is where it's at...." Proverbs 15:30 .... "A Cheerful look brings joy to the heart, and good news gives health to the bones..." Be exceedingly blessed today, my friends!...



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