Howdy , got a 84 Sub. did the 134A conv. on it cant get it to blow any less than 60 degrees, at 1200 rpm, gauge readings are low 35 , high 200

it has rear air ; I did the following replaced the compresser with a NAPA rebuilt, new dryer, new orfice tube , replaced the capillary tube on the rear unit,, Expansion valve there forgot what it wasa called fer a minute.,,, flushed the entire system, replaced the oil as required, Vac the system down an recharged the system.

Now Ive probaly done about 200 of these conversions an had little problem till now.,,, I did notice that if I ran a garden hose over the condenser that my head pressures drop to like 25 low an 150 high , thats with both units running at 1200 rpm , the engine up to oper. temp clutch fan on engine kicked in an also aux elec fan going on Rad..

I had a host of problems with this vechile, the old compresser had locked up, an the had the look of what the Ford guys call black death of the ac unit , the orifice tube had some very lite metal on it an covered with this fluffy black powder, also the evap core was plugged on the outside with dirt an oak leavescutting down on the air flow to the cab,,, an the expansion valve on the rear unit was plugged up the same stuff as the orfice tube

After I got every thing hooked up an going I was only getting like 76 degrees in the cab, I had good readings on the gauges, , both units were sweating, high side lines very hot , low side lines were very cold to the touch, had me scratching my head ,,, I found the heater shut off valve was bad an dumping hot air in the cab,,,,SOooooo I fixed that,, found the fresh air / max rec, door was stuck part way open fixed that,, got the cab down to 60 degrees wont go no more ???? any idea?????,

Iam thinking the condenser on the front may be partilly plugged internal, man I got more hours in this thing then I care to think about

 

go with your gut, do you have the right orffice tube, you may have to drain and check you orffice tube and see what you have front and rear. hope this helps