The 1947 - Present Chevrolet & GMC Truck Message Board Network

The 1947 - Present Chevrolet & GMC Truck Message Board Network (https://67-72chevytrucks.com/vboard/index.php)
-   The 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board (https://67-72chevytrucks.com/vboard/forumdisplay.php?f=4)
-   -   Air Conditioner help! 85 C10 (https://67-72chevytrucks.com/vboard/showthread.php?t=674905)

Zach079xxx 06-26-2015 03:28 PM

Air Conditioner help! 85 C10
 
Hey guys this Virginia heat is getting a little extreme. I bought my truck about a year ago, I wanna say the AC worked back then. But for the last few months it hasn't worked. I replaced the blower motor, thinking maybe it was weak, which anyways it was probably time for a new one. I also replaced the vacuum switch behind the controls. Then today I popped the hood and with the AC running I looked at the compressor and saw a caulk or putty kinda deal, I felt air shooting out of it, shown in picture! I pulled it off and it really started coming out. Why would air be coming out of it? What can I do? Can I putty and JB Weld it back up? :waah:


http://s13.postimg.org/5ouhnpgwn/IMG_8994.jpg

http://s1.postimg.org/eey2pn2bz/IMG_8993.jpg

I know I have a vacuum leak inside the cab also. I was told with controls on Max AC air should NOT come out of the floor, which it does :( I'm stumped on it. Also heat blows maybe atleast twice as hard as cold. Maybe someone has had this problem before, or similar. I AM STUMPED lol!

RUN GMC 06-26-2015 03:56 PM

Re: Air Conditioner help! 85 C10
 
Your leak is inside there your evaporator....replace it........

Zach079xxx 06-26-2015 04:06 PM

Re: Air Conditioner help! 85 C10
 
How bad is it to replace it? What should I watch for? Is this why my AC isn't blowing cold?
Quote:

Originally Posted by RUN GMC (Post 7222567)
Your leak is inside there your evaporator....replace it........


hatzie 06-26-2015 04:34 PM

Re: Air Conditioner help! 85 C10
 
With the blower on or off?
I assume it's shooting out with the blower on because the airbox is leaking around the AC pipe. That's usually because the black butyl and cork sealer has gotten brittle and not as sticky from age.
You'll need some "cork insulation tape". The old timers called it dum dum tape.
Wrap several layers around the evaporator pipes and into and over the hole in the fiberglass evaporator box. That'll block the leaking fan air and force it into the ducts in the cab rather than exhausting it into the engine bay.

If the evaporator was leaking then shortly, in a few seconds, the Freon would discharge and compressor clutch would disengage. Then the leak would stop because there's no more freon to leak.

Zach079xxx 06-26-2015 04:44 PM

Re: Air Conditioner help! 85 C10
 
My compressor never disengages unless I switch it off. I'll seal it up and see how it goes. Thanks!
Quote:

Originally Posted by hatzie (Post 7222605)
With the blower on or off?
I assume it's shooting out with the blower on because the airbox is leaking around the AC pipe. That's usually because the black butyl and cork sealer has gotten brittle and not as sticky from age.
You'll need some "cork insulation tape". The old timers called it dum dum tape.
Wrap several layers around the evaporator pipes and into and over the hole in the fiberglass evaporator box. That'll block the leaking fan air and force it into the ducts in the cab rather than exhausting it into the engine bay.

If the evaporator was leaking then shortly, in a few seconds, the Freon would discharge and compressor clutch would disengage. Then the leak would stop because there's no more freon to leak.


Dead Parrot 06-26-2015 06:11 PM

Re: Air Conditioner help! 85 C10
 
check out the following thread: http://67-72chevytrucks.com/vboard/s...d.php?t=460942

A lack of vacuum or a broken plastic thing that is shown in post #5 of the other thread will result in the blown air coming out of all of the outlets. In my case, it was a broken white plastic thing.

If your heat/cold flapper is leaking or out of adjustment, the heater core might be competing with the A/C. A quick test for that is run the A/C with a cold engine. If the air starts off cold and becomes less cold as the engine temp warms, suspect the heat/cold flapper.

Zach079xxx 06-26-2015 07:12 PM

Re: Air Conditioner help! 85 C10
 
I pulled the vaccum line off under the dash and it was sucking air. The garage I deal with has been shabby lately and I might get someone else to see if it needs to be charged. It's simply just not cold, it's cool but not cold. And I'll try the start method you mentioned Dead Parrot. Thanks everyone that's mentioned something!

homemade87 06-27-2015 08:42 AM

Re: Air Conditioner help! 85 C10
 
Zach , I used and electrical puddy use on houses to seal the top of the wire entering the electrical box outside . I picked up mine at the local building supply . This worked great on the a/c box . Its a soft puddy that's made to withstand the elements . It comes in a small brick wrapped in plastic . Dont use anything that permanent . Pain when it comes to service .

Also I agree about the broken plastic thing( need to check it out ) . If you have air coming from multi vents you need to correct this first before anything . Need to find out why .

Zach079xxx 06-27-2015 11:42 AM

Re: Air Conditioner help! 85 C10
 
Thanks! I got them sealed up and will be moving onto the vents sometime soon!
Quote:

Originally Posted by homemade87 (Post 7223079)
Zach , I used and electrical puddy use on houses to seal the top of the wire entering the electrical box outside . I picked up mine at the local building supply . This worked great on the a/c box . Its a soft puddy that's made to withstand the elements . It comes in a small brick wrapped in plastic . Dont use anything that permanent . Pain when it comes to service .

Also I agree about the broken plastic thing( need to check it out ) . If you have air coming from multi vents you need to correct this first before anything . Need to find out why .


Axle 06-30-2015 09:09 PM

Re: Air Conditioner help! 85 C10
 
While you are doing that, remove the blower resistor and look at the evaporator and see if its coat a blanket of dust and debris on it, if so, you might get lucky and get it mostly cleaned up with a hose taped to your vacuum that you can fit through the blower resistor hole if you don't want to take anything apart. yet. =-)

ALex.

Zach079xxx 07-01-2015 12:19 AM

Re: Air Conditioner help! 85 C10
 
Thanks I'll try that
Quote:

Originally Posted by Axle (Post 7226874)
While you are doing that, remove the blower resistor and look at the evaporator and see if its coat a blanket of dust and debris on it, if so, you might get lucky and get it mostly cleaned up with a hose taped to your vacuum that you can fit through the blower resistor hole if you don't want to take anything apart. yet. =-)

ALex.



All times are GMT -4. The time now is 10:16 PM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2025, vBulletin Solutions Inc.
Copyright 1997-2025 67-72chevytrucks.com