Old A/C 134a conversion needs help

[agm2003]

I have an '86 Camry (215,000 miles) with 134a Conversion (done professionally with new compressor 12-15 years ago.) Live in S. Georgia where we've had 7 days in a row over 100 --with HIGH humidity.

A/C never really gets cold. After a few miles, it'll blow 80 degrees (still cooler than ambient). This morning, it actually blew 60 degrees (with ambient about 75 degrees)--this is the first time I've seen that in years! It actually gave me hope that it might can be improved.

Low pressure side is generally normal (although I haven't checked it later).

What has worked for the rest of you?
Seems I've heard that the fan (on radiator) may be inadequate, but can't find anything on this?

Was hoping I could get some guidance from some of you much more knowledgeable folks. Any suggestions?

Thanks,
Gary

[Doctor J]

This is very common on 134a conversion.
If the system conversion have been done with necessary materials, Freeze 12 can cool better then pure 134a.

[fredk]

you change the drier and whats the pressures of both sides?

[agm2003]

1--How to I change to Freeze 12 from 134a?
2--I'll check the pressure on low side (I don't have full guages).

BTW--Last year a guy put in a can of "Cooltop" he said would help. It seemed to help some, but not much.

[Doctor J]

The LOW side with R134a typically reads 60PSI [vs. 28 psi on R12 or freeze12]
r134 a is vacuumed out and freeze 12 is dumped in.
the drier sight glass ALWAYS have cloudy appearance with 134a or freeze 12.
If drier is restricted it will have large temperature difference before and after it.

[typesix]

Also, if you don't already, use the Recirculate mode after driving a few minutes to minimize hot air intake.

[agm2003]

I don't think the low side is that high--I'll check it when I get home. Should that be while running or while the engine is off?

Yes, I ALWAYS use recirculate in this car after clearing the cabin.

[Doctor J]

When running; this is maximum; I saw the reading of 50

[fredk]

if the fans are blasting and the small line where it goes inside the car is red ass hot the condenser is not getting rid of the heat and the hi side will be hi

[agm2003]

I will check the lines.

BTW--Sorry about the delays in responding. I'm having trouble with loggin in and staying logged in. Every time I try to reply, it won't allow me to do so. I think it's my system.

I DO really appreciate everyone's input, though, as I really need the help.

[ChevyToughRebel]

I also did the R134A conversion myself with all the original parts intact, my A/C works fine. There is a huge list of things that could be the cause of your problem, I have the factory service manual in front of me. Did your A/C work good back when it was converted? If so did it all of a sudden start acting up, or has it been a gradual thing.

To better diagnose the problem, we need to know exactly how the A/C system is functioning. The most common problems I have come across for an A/C system that does not turn on; Relays, bad connections, low refrigerant, bad compressor clutch, bad compressor (noisy or locked up), and pressure switches. For an A/C system that does not cool properly; Low refrigerant, faulty thermistor/thermostatic switch, improper cooling of the condenser, faulty pressure switch, faulty expansion valve.

First things to check however include the cooling fans, make sure that both of them turn on when the A/C is on. Also make sure that the Compressor clutch engages when you turn the A/C on. Low refrigerant will also cause insufficient cooling. If your reciever dryer has a sight glass on it, there is a trial and error that can be done to decide if you have too little, too much, or the proper level refrigerant in your system. The factory manual shows a refrigerant amount of 1.3 - 1.7 lbs. The factory manual I have is for 87-91 Camrys, so I dont know what all will pertain to your car apart from the basics. The factory manual shows normal low side pressure of 21-28psi, and high pressure 206-213psi using R12, 90degrees ambient temperature, engine rpm @ 1500. R134A will show a higher reading, also higher ambient temperature will show a higher reading. These readings will flucuate with the compressor clutch engaging and disengaging, and the cooling fans as they cool off the refrigerant flowing through the condenser.

If you can, give us a detailed description of what exactly is your A/C is doing if you are unable to resolve it. Hope something I wrote helps.

~ Shane

[DC 2vzfe dx]

why don't you get everything vacuumed out and check for leaks and then refill with r134....

[agm2003]

Thanks for the great input. I will begin checking these things and get back to you.