Twisted

So I went and got a can of R134--I think it's called measure and charge or something like that. I went out to my car, and popped the hood. I saw two fittings: One that is directly on the condenser (on the right side), and another that is on the line running from the condenser into the firewall area (on the left side). The one that I thought was the lowside fitting (the leftmost fitting--the one on the coolant line) is not a snap-on fitting like the other fitting is (the one directly on the condenser...on the right). Instead, it is just like the fitting on a tire valve. Then I started thinking that maybe the other fitting is actually the lowside fitting, and the correct fitting for recharging. So I connected the R134 can to that fitting, just to see what kind of pressure was in there. Well, there was a lot of pressure in there--so much that the guage on the R134 can shot into the red zone (overfilled). Then, I disconnected the can, and started the car. I looked under the hood and noticed that my condenser clutch is engaging and disengaging about every three seconds. My questions are:

1. Has my system actually not been converted to R134?
2. Does the fact that the other fitting has such high pressure mean that my system actually isn't empty...that maybe there is no leak?
3. Why is my condenser clutch engaging and disengaging every three seconds or so?
4. Which is the highside fitting, and which is the lowside fitting?

sdmaker

do you have a fitting right up by the top of the compressor? thats where my low side fitting is. but mine is an 87. but if it has not been converted, you would not have been able to connect the r134 can. and the r134 can will only connect to the low side.

Twisted

Yes. The fitting that is directly on the condensor is the snap-on type fitting. The other fitting that is on the coolant line is a tire valve type fitting.

sdmaker

ok two things can cause the low side to read high, overcharge, or mechanical problem in the system (usually bad compressor)

Twisted

Thanks for the info. Now, if the system was overcharged, would that cause the compressor clutch to cycle on and off every three seconds or so? Any idea what this means?

FiveLiterRiceEater

the tire valve looking fitting is on a line coming off of the compressor right? that should be the high side. theres another fitting on the comp that will be the low side. when you're charging the system your car needs to be running, with the a/c on. also you need to hold the can upside down when you charge. the clutch is probably cycling due to a low charge. you may also need to adjust your clutch cycling switch

Twisted

Thanks Fiveliter. Yes the tire valve type fitting is on a line coming off of the compressor, to the left of the other fitting--I may have accidentally said condensor before. So I can assume that the system has been converted if the fitting on the compressor is a snap on type, onto which the fitting on the R134 can fits perfectly? Also, I didn't have the car running when I checked the pressure. Is that why the pressure read so high?

FiveLiterRiceEater

probably. put your guage back on the low side with the car running, the low side is the side you had it on. it should drop way down

sdmaker

could have been why, lol. it needs to be running, with the ac on high like he said. then if i checks out low, dont just fill by the green pressure reading on the gauge. fill it slowly and when that line starts to sweat and gets really cold, then you are full. just use the gauge as reference.

FiveLiterRiceEater

yep. fill it nice and slow. dont let your low side pressure get too high and watch the line coming out of the accumulator, back by the fire wall. when it starts getting frosty, or just really damn cold, your there.