[Tim Hancock]

Steve, on a somewhat modern car with factory 134, the quick dirty easy method is to buy a couple cans of 134 and a hose/valve combo and after figuring out FOR SURE which is the low side fitting, hook the can up per the instructions, start the car, turn on the AC full blast, actuate the can piercing valve keeping the can right-side-up and refrigerant will start flowing into the system.

-High idling the engine to 2000 rpm while charging helps.

-The can will get cold and the flow will slow as the can pressure drops and system pressure rises. To get the remaining 134 out of the can and into the system, the easiest way I know of and do every time I add 134, is to use a hair dryer to heat the bottom of the can which helps it vaporize and enter the system. This can often take many minutes.

-When the can is empty, (the bottom is no longer cold) close the valve then remove the charge hose from the car's fitting. If the vents are now blowing cold (maybe 40-45 degrees or so on an 80 or so day, call it quits and enjoy, if the vent temps are not cold enough yet (55-60) try adding some more (maybe 1/2-1 can) and check again..... This "normally" will be plenty if your car was still blowing "cool" when you started and just have a slow leak.


The above will "work" often even on an older system that has been down for a long time, but the proper way is to find/fix the gross leak, install a new drier, evacuate the sytem to remove moisture with a vacuum pump, recharge using gages and thermometers to monitor for a proper charge.

I have brought old dead systems to life using proper equipment and I also just often squirt a can in my working but slow leaking systems. I just topped off my daughter's '87 924s and my '92 BMW 325 tonight using the first method I described above (924s took 1.5 cans, and the BMW took one can) both blew barely cool in 85 degree weather last week and now are in the low 40's with a digital thermometer in the center vents).