Redog

85 delta 88

Nothing is marked! I picked up a can of 134a and would like to put it in but fear the can exploding if I connect to the high side. I know the fittings won't fit the high side, but that's on 134 only cars. Mine was orginally r12 but is has a sticker saying it will take both kinds. One port is behind the compressor and the other is by the heater box. The hose looks like it will fit the one by the heater box buy I think that's the high side. When I take the cap off the one behind the compressor it hisses and stuff leaks out from trying to hook up the hose. Never seen that before

anybody know?

GAOldsman

Sounds like you've found your leak.....

GAOldsman

Big line = low pressure
Little line = high pressure

Oldsmaniac

Well it can only take one kind of refrigerant as they cant be mixed. Most likely someone converted it to 134a. There is a small cannister (accumulator) that is aluminum. This should have a charging port on it and that would be the low or suction side. The high side comes from the compressor and goes to the condenser at the front of the car. It comes out of the condenser and thru the metering device to the evaporator on the firewall. From the evap back to the compressor is the low side.

rocketraider

To simplify things, the port closest to the heater box is the low-pressure side. The one at the compressor is the high pressure.

What type of fitting do you have? A 134a conversion should have large plastic screw-on caps covering the charging ports- a quality job would have had a red and a blue cap, though some just have two black caps. These fittings look similar to an air hose quick-connect fitting and the caps thread into the center of the ports.

R12 ports are external thread and caps can be aluminum, brass or plastic.

Redog, if you aren't totally sure about this thing, get someone familiar with it to help. If there's a community college with an auto technician program near you, their instructors are usually top-flight.

If the car has not been converted to 134a, the 80s B cars take the conversion well. I've done three of them and they all blew 40 degree air on the road with a 36 oz refrigerant charge.

Me wagon needs a compressor, accumulator and orifice tube bad, but I didn't have time to do it when it was cooler and I'm damned if I'm gonna tackle that job in 100 degree heat. Ought to just take it on over to the CC and let them change it. That's where I did all three, taking summer session night classes.

MDchanic

R134 fittings are different sizes for the high and the low side.

R12 fittings are both the same, but are different from 134.

If it's been converted, you can't make a mistake.
If it hasn't then you don't want to put 134 in it, and the ports won't match up anyway.

- Eric

Redog

The 2 ports on the Delta are different sizes. I do have 2 black plastic caps and the hose should fit the one closest to the heater box. I'll try the hose BEFORE hooking it up to the can or 134a I bought. I just didn't want the can to pop in my hand

On my Alero the low side has a light blue cap with a big "L" on it and it's lower than the one in the front with the black cap on it. I just thought that the low side, was also lower than the one for the high side, considering how far down that A/C port actually is. Guess I learned something new

MDchanic

With the A/C off, the pressure will be the same on both sides, so there is no danger of it being too high on one or the other.

With the compressor running, there should be a significant difference between the two sides.

If the pressure is too much, the relief cut in the bottom of the can will pop, so if you're worried, point the bottom of the can away from you.

- Eric

made in the usa

the can wont explode in your hand doesn't matter if hooked wrong or not. The funny half moon mark on the bottom of the can will pop open that's actually what its designed there for. In case of over pressurized systems or being hooked up incorrectly might scare you but wont kill you. Does sound like you need to convert your system over the system must be evacuated and they have a oil conversion that suppose to work for the conversion.I have never tried it i have always changed out my compressor and accumulator and orifice tube. Most vehicles can be done for under 300.00 if you do it yourself.

joe_padavano

Funny, I just had exactly this problem on my truck. The valve core is bad. Unfortunately, unless you have access to one of those trick tools that allow you to replace the core without losing pressure in the system, you will need to completely vent the system to replace the core. Once you do that, you need to use a vacuum pump before filling again.