Air Conditioner help! 85 C10

[Zach079xxx]

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?






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]

Your leak is inside there your evaporator....replace it........

[Zach079xxx]

How bad is it to replace it? What should I watch for? Is this why my AC isn't blowing cold?

Originally Posted by RUN GMC

Your leak is inside there your evaporator....replace it........

[hatzie]

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]

My compressor never disengages unless I switch it off. I'll seal it up and see how it goes. Thanks!

Originally Posted by hatzie

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]

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]

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]

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]

Thanks! I got them sealed up and will be moving onto the vents sometime soon!

Originally Posted by homemade87

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]

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]

Thanks I'll try that

Originally Posted by Axle

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.