Topic: R4 Compressor Oil Drain
in Forum: C3 Cooling and Heating Systems
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Lifetime MemberModerator
Moses Lake, WA - USA
Joined: 4/16/2005
Posts: 2134
Vette(s): 1976 L48 4-spd, Mahogany Metalic exterior, Buckskin interior 350ci/350hp, 3rd owner, fiberglass spring, 255/50-16's Torq-Thrust II
Since I lost my low side hose on the A/C system I am going through it. I want to drain the oil out of the system so I have a starting point on refill. How do you drain whats left in the compressor. I can't find a plug so do you just set it with the ports down and let it drain?
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Duncanville, TX - USA
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The R4 compressors don't have plugs, like the A6's do.
You'll need to remove the comp. and stand it on end to drain as much as you can out of it. You should turn the clutch every now and then to help move the oil out of the cylinders.
It doesn't have to be completely dry of oil. A small amount won't hurt. Just get as much as you can out of the comp., the evaporator, and the condenser. I assume you will be replacing the accumulator/dryer, if you have one?
('76 was the year they went from the VIR system to the orifice/accumulator, so you could have either system.)
You'll need to remove the comp. and stand it on end to drain as much as you can out of it. You should turn the clutch every now and then to help move the oil out of the cylinders.
It doesn't have to be completely dry of oil. A small amount won't hurt. Just get as much as you can out of the comp., the evaporator, and the condenser. I assume you will be replacing the accumulator/dryer, if you have one?
('76 was the year they went from the VIR system to the orifice/accumulator, so you could have either system.)
Joel Adams
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Lifetime MemberModerator
Moses Lake, WA - USA
Joined: 4/16/2005
Posts: 2134
Vette(s): 1976 L48 4-spd, Mahogany Metalic exterior, Buckskin interior 350ci/350hp, 3rd owner, fiberglass spring, 255/50-16's Torq-Thrust II
Thanks Joel
I bought a rebuilt VIR valve, pressure switch, hose assembly and o-rings. I pulled the evaporator to drain and clean the fins. They were real dirty and had little dried leaves in them. I should get some pretty good air flow out of it know.
I bought a rebuilt VIR valve, pressure switch, hose assembly and o-rings. I pulled the evaporator to drain and clean the fins. They were real dirty and had little dried leaves in them. I should get some pretty good air flow out of it know.in Forum: C3 Cooling and Heating Systems
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