R134a Leak Question

[jpabberton]

I upgraded to a R134a system, compressor and all the rest, but kept the old condensor. My truck has factory AC. I am leaking refrigerant and cannot locate the leak anywhere. Took apart the evaporator and everything. Every second or third start up after cool down the sniffer will go off from the center vent with the A/C blowing high. Nothing consistant. I am blowing 44 degrees at idle with the addition of an electric fan. Any suggestions?

[68gmsee]

Here's what I know re: converting from R12.

You have to change all the seals in the system to the new style. Also, in some cases, the rubber hoses. The reason that is that 134a is composed of smaller molecules than the old refrigerant therefore able to escape easier through hoses and seals.

I changed several of my older vehicles in the past and did all the seal replacement. Usually did well in containing the 134a.

I'm not sure but it seems 44 degrees is low at idle. I always tried to get in the low 50's with mine.

[stope4]

need to change all the orings. Use the green ones. If you are getting warnings at the vent almost the only place to have a leak is in the evaporator. Did you change this? If not Olde Air sells new ones. I'd also recommend changing the condensor to one of the newer parallel flow types. (http://www.ackits.com/c/Parallel/Par...+Aluminum.html or http://www.classicautoair.com/CPickup6772.asp )They are designed for 134a. Have smaller tubes but 3 or 4 times more. This equates to more surface area, which equates to more cooling or heat loss in the refridgerant.