a/c question

[beotch2]

Hello I am trying to get my ac working in my 84 GN The problem is that when I turn on the car and turn on the ac the air is coming out of the defroster not the vents. When I unhooked the vacuum lines assembly from the back of the a/c control panel on the dash their was no vacuum. I am trying to figure out where the vacuum line connects to from the engine to the vents.

 

[turbo nasty]

My car was doing the same thing. a bud that works on GM's said that the o ring in the selector assembly(max a/c, bilevel, etc) gets dry and worn and does not route the vacum right.

I was about to fix it and now the whole assembly is froze to the off position ...go figure. I will be tearing into it this weekend toi see what is up.

 

[turbo nasty]

Duh

I just read your whole post. The lines that go to the switch come through the firewall by the ECM, on the engine side will be hard plastic emission tubing and in the cabin will be softer colored hoses. In the engine area one comes off of the heater valve and the other I believe comes off the back of the motor and over.

 

[chevyII]

A/c

look under your hood there will be a vaccum line diagram for the entire engine. should be on the radiator support next to the emissions tag.not many people realize its there and put the lines in the wrong spots.

 

[digorok]

Vacuum lines

Check to make sure you have vacuum to the control unit in the dash. If you do just change the control unit (looks like a spyder). Any good auto parts store can order it for you. If you don't have vacuum, you'll need to trace the line and find the leak. The line goes from the passenger side firewall, along the firewall to the drivers side, to a vacuum ball under the front drivers side corner of the car, and back the the engine.
Look for the underhood vacuum sticker. It will give you an idea what to look for.
I have a diagram if you want to check the vacuum control hoses under the dash.

 

[77tech9]

My a/c works fine on slightly hot days, but when it's over 90 degrees outside it just can't keep the car cool.

I changed to r134 but I think something else is wrong, it's just not as cold as it should be

 

[beotch2]

Ok thanxx i think I figured it out my vacuum line going from motor to the booster assembly under dash was completely gone.

 

[digorok]

to 77tech9

Check your fan. If it's not pulling enough air through the condensor to cool it down, the A/C will not cool well. The cooler you can keep the condensor, the cooler the A/c will be. Also check for rubbish blocking the air flow in between the condensor and the radiator.
Best thing to do is to install the Ramchargers duel fan set-up.

 

[77tech9]

Maybe I should goto a 160 thermostat and it might cycle the radiator more, could be running hot?

I checked and cleaned the front totally, we'll see how it runs.