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76 300d A/C

744 views 6 replies 4 participants last post by  Dlamazing 
#1 ·
Ok to start the car had a vac issue at first i did not know this car had a vac actuated relay for the a/c till I read on it here so that's to this forum I figured that out, anyways fixed the vac diaphragm and boom a/c blower kicks on and heater turns off and my comp kicks on to (York comp) ok this car had the r12 system of course it had barely no r12 in it so I bought the R134a conv fittings I evacuated the system including the old oil if it even had any I vacuum the system for about 45min it held vac so I know it's got no leaks so I put oil in the system 3 oz and 1lb of freon to start wasn't cooling kept adding till it cooled but the compressor don't like when the pressure gets to like 225 high side it starts to lock up the best cooling happens with like 2lbs of freon but even then it's not a true 100% cold it's weak! I know this car is a dinosaur lol was thinking of starting off with a new drier and expansion valve and go from there but I thought I would be lucky like everyone else here they charge it and boom ice cold a/c any thoughts????
 
#5 ·
Why do you say that? Looks like its in healthy shape thing pulls pressure pretty good I'm not trying to spend 200+ dollars on a new one over a little power the car it self is slow so a couple more horsepower isn't gonna make it any faster lol plus I read good things on that compressor besides the bushings going bad
 
#7 ·
How much oil does it take you know? I put 3oz maybe since its bigger it takes more???? Idk but this thing has yet to cool and don't know why! Also the pressures read different since the service ports are so close to the compressor it's a guessing game pretty much add enough so the compressor kicks and add from there till it starts to cool which mine just get decent not cold like it should smh
 
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