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A/c Question

Tinman761

New Member
Hello everyone, new member here. I have a 91gt convertible. Im having an issue with a slow leak in the system. It used to hold a charge but won’t hold anymore than about 2 days. I have evacuated the system and pressure tested with no success. Years ago, you could put in dytell to find the leak but not sure that’s even available anymore. Is there a problem area I should concentrate on? Thanks for the help everyone. Joe
 

347HO

Active Member
In most systems, the lube oil is fluorescent green and can be seen at leak points.
The best way to find your leak is to use a "sniffer" which detects r134 when you pass the tip over the leak.
Most common places are joints and the Schrader valves on the high and low side fill connections.

Good luck
 

Tinman761

New Member
In most systems, the lube oil is fluorescent green and can be seen at leak points.
The best way to find your leak is to use a "sniffer" which detects r134 when you pass the tip over the leak.
Most common places are joints and the Schrader valves on the high and low side fill connections.

Good luck
Thanks for the reply. I am still using r12 and have a sniffer also, but still can’t find it.
 

347HO

Active Member
The system requires a bit of charge, the pump it up to check the high side.
I'm not aware of anyone charging systems using r12. Its a pretty huge fine. But you can charge with 134 without a problem.
You can get away with pushing shop air and sniffing for the leak, but you won't be able to pump it up, due to the pressure switch not closing or opening depends on flavor of the system.
 

Tinman761

New Member
The system requires a bit of charge, the pump it up to check the high side.
I'm not aware of anyone charging systems using r12. Its a pretty huge fine. But you can charge with 134 without a problem.
You can get away with pushing shop air and sniffing for the leak, but you won't be able to pump it up, due to the pressure switch not closing or opening depends on flavor of the system.
Found the leak, it was the rubber seals on the line going into the evaporator at the firewall. Changed the seals and it now on a vacuum. We shall see. If this doesn’t work. I may change over to 134a with that kit from lmr.
 

347HO

Active Member
Sweet. Hope that fixed it.
Dobt know who/where you take your car to have the a/c serviced, but my machine does a leak test prior to filling and lube. I don't charge a customer for the leak test and finding it has a leak... Its integrated into the servicing!
Hope this will be the same for you when you finally have the system filled.
 
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