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73-87 Chevy _ GMC Trucks => 73-87 Chevy & GMC Trucks => Topic started by: DrDaryl on August 14, 2011, 11:15:30 pm

Title: A/C problem
Post by: DrDaryl on August 14, 2011, 11:15:30 pm

Hi guys maybe someone can help me out a bit.  I finally got around to working on my truck's AC; got a new R4, new condenser, new hoses, orifice tube, and accumulator.  Got R12 from ebay; put 6 oz mineral oil in the compressor and 4 oz in the accumulator (from Autozone specs).  Pulled a vacuum for an hour and it held with no leaks.  I put 18 oz of R12 in last night.  I put the gauges on it tonight to check things and  with the compressor engaged the high side started climbing steadily and was pushing 400 when I shut it down.
The pipes on the evaporator stayed warm.  The orifice tube had an arrow on it and I am positive I inserted it into the evaporator with the arrow pointing toward the evaporator.  I blew air through everything before assembly to check for obstructions.  I think it shouldn't have been that high??  Any thoughts?  Thanks

Title: Re: A/C problem
Post by: 1979C20 on August 15, 2011, 12:27:15 am

The long side of the orifice tube should point towards the liquid line to the condensor. The short side of the orofice tube should point towards the evap core. The whole system should take aboit 30 floz, if I understand correctly.

Title: Re: A/C problem
Post by: topp on August 15, 2011, 10:54:02 am

You should have also flushed the system parts to clean them out prior to sealing it up and pulling vacuum.