Ac compressor oil?

JimKueneman

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Did mine slightly differently. After I removed the EPR valve in my compressor I added an adjustable clutch cycling switch. Mounted it on a brace behind the glove box. Think it had an 18" long capillary tube on that particular model. Drilled a tiny hole (with a rubber grommet) in the ac/ heater box to put it's end in between the fins in the evaporator and wired the under dash a/c clutch wire in series to it. This switch has two adjustments. Cut in and cut out. Stuck a digital thermometer in the center a/c vent and set it at I think 34 degrees cut off and 40 degrees cut in. With a big block I really don't notice much of a RPM drop when it cycles. With a 225-6 probably more so unless there was an idle speed solenoid to up the rpm's when engaged. It doesn't start to get as cool initially as my 93 Taurus, but it gets way colder a short time soon and I'm turning it down to the low fan speed 5 minutes into my 10 minute drive home from work. This link prompted me to remove the EPR valve for improved cooling: https://www.forbbodiesonly.com/moparforum/threads/ac-compressor-oil.147951/page-2

Yea it has to get the heater core antifreeze cold but man after it does that old V2 will freeze you out!
 

bearman

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That sounds great the way you did that. That just might be the right idea for most of these guys that are looking to make 134a work in a r12 system.do you run a electric fan for condenser or mechanical on the engine
 

hyde-park

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On my car everything is stock cooling wise. Two row factory radiator, 180 degree t-stat, stock 7 blade viscous fan w/ shroud. I did add police transmission and power steering coolers. I'm still running with what I call automotive heroin IE: R12. It's illegal and high priced, lol!
 
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bearman

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The only reason that it takes a little longer to cool down is because of the transfer between gas and liquid in the condenser the faster you change the gas to liquid the faster it will cool down. Like the newer cars they run three and four core and don't forget the swirl coils this was for one reason only and it was change the gas to liquid. Here is a test go take a ray gun and take a temp reading at the intake of the condenser and then take temp at the bottom get the number.. then grab a house gan and put it front of the condenser start watching the bottom number change and time the inside temp you should see a 5plus drop faster than when the extra fan is not there. If you want to see a real fast change run the a/c then take a bucket of water and throw ot on the condenser watch the inside temp really start coming down.
 

bearman

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Thanks again jim I'm not that bright on this computer stuff . But yep that should help everyone out. The info that you just put out is great and very helpful. Thank you again
 

vtg air tech

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I bought a converted rebuilt R134 compressor, new dryer, new evaporator, and condenser. Only reusing the lines. What should I clean the lines out with? Brakekleen or similar?

If your using the old R-12 hoses (non barrier) with R134a they will leak. R134a has a much smaller molecule than the R-12 and will leak right through the hose.
 

JimKueneman

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If your using the old R-12 hoses (non barrier) with R134a they will leak. R134a has a much smaller molecule than the R-12 and will leak right through the hose.

If they are old the mineral oil has already seeping into the hose and plugged the larger holes. I have my original hoses going in 2.5 years with R134 and still is full.
 

vtg air tech

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If they are old the mineral oil has already seeping into the hose and plugged the larger holes. I have my original hoses going in 2.5 years with R134 and still is full.
That is possible, and if you are using ester oil There may not be an issue for some time. But if you are using a PAG oil with the R134A system and there is any amount of mineral oil in the system it will cause contamination.
 

JimKueneman

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That is possible, and if you are using ester oil There may not be an issue for some time. But if you are using a PAG oil with the R134A system and there is any amount of mineral oil in the system it will cause contamination.

I am using ester
 
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