AudiSport4000

On my 86 4kq, the AC has never blown cold, but the compressor kicks in and works. I have no knowledge of HVAC systems at all, so I need help.
I asked my tech about converting over to R134, and he said he thought my car had already been converted over. How can I visually check to make sure hes correct? If I wanted to refill the AC, what port do I use, and where is it at?
Any other fun AC help?

Mike

Evilclown

Check the fittings. If they're press-on quick release type, it's 134. If they're threaded, they're R12. To refill the A/C if you have 134, head down to your local parts store and tell them you need to recharge your AC system, and that it's 134. They'll hook you up with what you need.

StormChaser404

Nothing he said makes it sound like it is low. if it were low, you could check the site glass on the reciever dryer for bubbles and the compressor would be kicking in and out (clicking) quite frequently. So, it COULD be low, but he has said nothing to indicate that it is. For all we know it could be over charged. Overcharging reduces cooling just like under charging. it could also be that his temperature sensor is out of whack, or his expansion valve is gummed up, or ...or ....or...it could be any number of things...we need more info to help determine the problem.,..

Cdn Blue Coupe

ditto

Evilclown

Never knew that about overcharging.

austinado16

As Dave says, there are a whole bunch of things that can cause poor output. So, work from the simple toward the more complex solution.

1) With the A/C on is the recirculation flap closing completely up in the fresh air well under the plastic shield?

2) With the A/C on and the compressor engaged, do you see bubbles in the site glass at the top of the receiver/dryer? This the tall soda pop can shape deal mounted to the front of the car down near the compressor. Take your finger and wipe off the round glass "eye" on the top of it. You should see liquid refrigerant flowing. If you see bubble flowing, the system is low on refrigerant.

3)With the A/C on, is the radiator fan cycling on and of? It needs to be working.

4)Is the condensor covered with leaves and debris so it can't transfer heat?

Fix what's not right in these areas and then see what you've got. If it's still not blowing cold enough....which was the case in mine even after I recharged it with R-12.....then:

1)Is the compressor cycling on and off? If so, at what tempurature blowing out the vents?

2)What are your highside and low side pressures?

3)Adjust the temp sensing unit per my previous thread's instructions using a calibrated thermometer.

JeromeS.

My opinion is, your just guessing if you don't know pressures first.

On the other hand, I don't have that much experience with diagnosing ac systems..only what ive done in school.

Hey Austinado, have you taken that ase refrigerant recovery quiz? What a joke..

austinado16

I agree, the pressures are important and if it came into a shop, the first thing they'd do is throw the gauges on it.

But, if he doesn't have a set of gauges...they're on ebay all day long for cheap by the way...then he can do alot of quick diagnostics on his own.

Eliminating certain things is just as good a method of diagnostics.

No, I never did take that darn test. I think it's still sitting in my tool box.

AudiSport4000

Where is the recirculation flap at, under the passenger footwell?

Mike

austinado16

Remove the thin black plastic shroud and then check to see if the flap closes when the A/C is turned on. While you're there vacuum out the 4lbs of dead leaves and pin needles and clean your drains.