Posted by METALMAN on Monday, September 16, 2002 at 8:54AM :
In Reply to: Air Conditioner posted by Chris on Monday, September 16, 2002 at 0:20AM :
Yes I have experimented with R134a sucessfully. R 12 as you must know is very expensive.Still availble if you have a Certification card at auto parts stores either in 12 oz cans or 30 lb tanks.So far I have done 2 conversions myself on older vehicles . I have not purchased a set of 134 guages as of yet. ( I have had a set of R12 guages + a vacume pump for many years).Also a while back I bought a small portable R 12 recovery machine + some other garage equipment from a shop that closed.I used to sucessfully recover R12 from the occasional junk car or wreck that system was intact but know most vehicles I see up here are 134 systems.I had a customer with a 80s era Olds that the compressor was bad so I took a used unit from a junk car blew out the compressor ,hoses, condenser,evaparator + receiver drier with compressed air.Was able to get specs on the correct amount of Pag oil to add to the system.poured it very slowly into the larger Low side Hose + into condenser then evacuated the system with my pump,let it sit to see if it holds vacume.Then put 134 conversion fitting on low side + calculated the amount of refrigerant I read that with a conversion about 80% of amount of R12 is correct due to the fact that 134 pressures run higher + used the site glass on receiver drier for content + thermometer in vent in cab.This car still on the road third summer since repair.This summer it needed just a small amount of 134 it must have a slight leak somewhere.The 2nd system I did was my own 91 Dodge Power Ram 4x4 Dsl Wrecker.A couple years back my compressor went bad + replaced it with a reman unit from Chrysler + charged it with R12.Last spring when I went to use that rig after I serviced it + took off the studded snows for the summer months ( it is now my spare Wrecker as I am runnin a 01 Dodge Dsl 4x4 as my #1 rig ) warm air so at one of my stops that I tow for in our friendly little almost crime free city of Plattsburgh I used his equipment + added some dye + a little R12 to see if I could find the leak + with a UV lite was able to find traces from a pin hole in the condenser.Ordered a new condenser from the Chrysler dealer + installed it 3 days later.Added the correct amount of oil to the new condenser + rest of system after blowin out R12 oil + runnin compressor to pump out any remainin R12 oil,Closed up system ,evacuated with pump,let sit to see if it held vacume then put conversion fittings on both hi + low side added correct amount of R134 + nice cool air .I used that rig a bit durin the summer + we do get some very Hot + Humid days here in the beautiful Adirondacks + feel no differnce in the cooling with the 134 conversion.I did have a slight leak at the hose block connection at one side of the receiver drier but it seems to have sealed itself.I just went out to that rig last week the day after I got out of the hospital it sits in its own garage by itself. I built the garage a few years ago away from my repair shop + put a lean to off the side for my Hot Rod Jeep.I climbed into it slowly + fired up the DSL + listened to the rattle of the Cummins .Let it idle for a bit air was ice cold so I guess system is leak free.