Page 11 of 11
Re: 1986 Corvette R-12 to R-134a Conversion
Posted: Thu Apr 20, 2023 10:42 pm
by swampy 6x6
hi
Always start with 90% going from R12 to R134a then charge according to
pressures high /low expected for the system
low around avg 28psi
high side no more than 250psi but lower below 200 is ideal . If high side is around the 250 psi really needs more condenser and or fan
txv system very full or close to as possible in sight glass eg above 90% charge
accumulator measure super heat and donot charge to flood compressor
txv check sub cool
check centre vent temp
engine rpm at 1500rpm
warm ambient over 75f
clamp heater hose
recirculation select
clean condenser and evap core
Re: 1986 Corvette R-12 to R-134a Conversion
Posted: Fri Apr 21, 2023 6:43 am
by Tim
I have my popcorn and waiting to see you get sub 200PSI on a vette with an ambient over 90!
- Bigassfan.jpg (83.13 KiB) Viewed 1144 times
Re: 1986 Corvette R-12 to R-134a Conversion
Posted: Fri Apr 21, 2023 7:08 am
by kenlou
swampy 6x6
hi
Always start with 90% going from R12 to R134a then charge according to
pressures high /low expected for the system
low around avg 28psi
high side no more than 250psi but lower below 200 is ideal . If high side is around the 250 psi really needs more condenser and or fan
txv system very full or close to as possible in sight glass eg above 90% charge
accumulator measure super heat and donot charge to flood compressor
txv check sub cool
check centre vent temp
engine rpm at 1500rpm
warm ambient over 75f
clamp heater hose
recirculation select
clean condenser and evap core
This makes no sense to me
Re: 1986 Corvette R-12 to R-134a Conversion
Posted: Thu Apr 27, 2023 11:55 pm
by swampy 6x6
hi
Kenlou
Very universal charging instruction that gives enough info so u donot get into to much trouble when charging system .
Re: 1986 Corvette R-12 to R-134a Conversion
Posted: Mon May 01, 2023 4:20 pm
by kenlou
OK...just want to give an update. I have been doing diagnostics with the help of a "corvette mechanic and friend". With his help, we found the Blower Control Module to be defective. Compressor is now running. I turned the compressor off and on a dozen times to burnish the hub and pulley face of the compressor.
As it is right now, I have no idea exactly how much refrigerant is in the system, but as it is, I get 48 degrees at the center vent, so it is definitely low.
As far as the quantity of r134a to put in, I am going with my 35 oz. I have sewveral articles and my FSM, and plenty of corvette owners that suggest 35.2 oz is what I want.
Now I guess I will take it back and have it evacuated and recharged again...but with 35 oz this time.