Reseal R4 Compressor
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Pro
Joined: Oct 2003
Posts: 506
Likes: 12
From: Savannah GA
Reseal R4 Compressor
I've seen the video on resealing a R4 compressor. Of course the guy didn't seem like it was his first time to the rodeo.
Wondering if anyone has done one.
I'd like to get rid of the oil streak under the hood.
I would rather keep my 30yr old compressor, it's not to noisy, instead of new china whatever or some other rebuild.
If I do it, going back with new accumulator and orifice tube and R12.
JS
Wondering if anyone has done one.
I'd like to get rid of the oil streak under the hood.
I would rather keep my 30yr old compressor, it's not to noisy, instead of new china whatever or some other rebuild.
If I do it, going back with new accumulator and orifice tube and R12.
JS
Race Director
Joined: Aug 2000
Posts: 11,470
Likes: 764
I've seen the video on resealing a R4 compressor. Of course the guy didn't seem like it was his first time to the rodeo.
Wondering if anyone has done one.
I'd like to get rid of the oil streak under the hood.
I would rather keep my 30yr old compressor, it's not to noisy, instead of new china whatever or some other rebuild.
If I do it, going back with new accumulator and orifice tube and R12.
JS
Wondering if anyone has done one.
I'd like to get rid of the oil streak under the hood.
I would rather keep my 30yr old compressor, it's not to noisy, instead of new china whatever or some other rebuild.
If I do it, going back with new accumulator and orifice tube and R12.
JS
http://www.rockauto.com/en/moreinfo....041208&jsn=488
Last edited by Joe C; Mar 30, 2017 at 08:54 AM.
Le Mans Master
Joined: Feb 2005
Posts: 6,485
Likes: 566
From: Clearwater Florida
(my 2-cents, FWIW) -- if you're running an original R4 compressor, AC Delco has a (new) service replacement compressor (ACDELCO 1520227) w/ clutch - price somewhere between $165-$175. I bought one when I did my 134a conversion, and its been on the car now for around 4500 miles without issues. I thought about rebuilding my original, but by the time your buy all new parts and seals PLUS a few specialty tools needed for the rebuild, and calculate the time and materials thing, well, for a few dollars more, it was worth the price of the new delco unit. form, fit, and function - pretty much on the money. rockauto's price comes in at $170.
http://www.rockauto.com/en/moreinfo....041208&jsn=488
http://www.rockauto.com/en/moreinfo....041208&jsn=488
... I went to the local AC Delco Parts House and bought a NEW compressor with clutch for less than $200 ... best way to go in my opinion ... put the old unit on the shelf and rebuild it at your leisure .....
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
Not really. AFAIK, R134A conversions don't cool as well as the R12 that the system was designed for without changing things around like the condenser. Cools better than without obviously but all things equal, on hot and humid days in stop and go traffic, the R134A conversion doesn't work quite as well.
Racer
Joined: Apr 2016
Posts: 336
Likes: 93
From: San Antonio TX
Not really. AFAIK, R134A conversions don't cool as well as the R12 that the system was designed for without changing things around like the condenser. Cools better than without obviously but all things equal, on hot and humid days in stop and go traffic, the R134A conversion doesn't work quite as well.
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Drifting
Joined: Mar 2015
Posts: 1,275
Likes: 165
From: Utah
R12 was a pretty good refrigerant from what I understand.
I drove my wife's grandparents car, an all original low mileage 1987 Honda something...
Factory R12...
The vents looked like when you open the freezer on a hot summer day, fog coming out of the vents it was so cold...
They also lived like a block away from the beach, so the humidity may have had something to do with it...
I drove my wife's grandparents car, an all original low mileage 1987 Honda something...
Factory R12...
The vents looked like when you open the freezer on a hot summer day, fog coming out of the vents it was so cold...
They also lived like a block away from the beach, so the humidity may have had something to do with it...
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
R12 isn't as available but not too expensive for what you get. Since I will never drive my car, any car without AC on unless it is in winter with the heat on, cooling is kinda important to me. Important enough to pass on any car without AC unless a repair is figured into the sale.,
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
R12 was a pretty good refrigerant from what I understand.
I drove my wife's grandparents car, an all original low mileage 1987 Honda something...
Factory R12...
The vents looked like when you open the freezer on a hot summer day, fog coming out of the vents it was so cold...
They also lived like a block away from the beach, so the humidity may have had something to do with it...
I drove my wife's grandparents car, an all original low mileage 1987 Honda something...
Factory R12...
The vents looked like when you open the freezer on a hot summer day, fog coming out of the vents it was so cold...
They also lived like a block away from the beach, so the humidity may have had something to do with it...
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
IIRC, the 94-96 C4 had R134A and the condenser was different. Next time my AC system comes apart, I'll try that one. As I was told, the system was designed differently so when you retrofit, you are doing a shoehorn operation which is why it isn't as good. That said, if the system is designed for it, the cooling will be as good as R12.
Team Owner
Joined: Jul 2004
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From: Hartford WI
Race Director
Joined: Aug 2000
Posts: 11,470
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on the topic of "efficiency-R134a vs R12" I can say first hand, and not by hearsay, that my 134a conversion is more than adequate for my needs. I did not use some Wal-Mart, conversion in a can thing, but a conversion by the book, and the book was from FJC. even with the hot summers and high humidity here in florida, my center duct temp are around 40°F (cruise) and around 55°F in traffic. I replaced the compressor, accumulator/dryer with new delco stuff, replaced the cycling switch, and orifice tube, and solvent flushed the system. ester oil and three 12oz cans of R134a - pressures within recommended ranges. my condenser and evaporator are original 85 hardware - cleaned inside and out. R134a may not be as good or as efficient as R12, but IMO, the difference is minimal. my conversion was not cheap, and i'm damn near embarrassed to say, but it was well worth it. - 
Race Director
Joined: Aug 2000
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Evaporator is the exact same configuration for 134 as it is for R-12. The threads are different for R134, but that is the ONLY difference. Size is exactly the same.
The main difference for the condensors that the 134 is a "parallel flow" design, and the R-12 is fin and continuous tube.
Evaporator housings and cores are the same. There's nothing to gain with changing the evaporator. The condenser needs to be more efficient for 134 because 134 condenses at lower temperatures than R12. But 134 boils at a lower pressure than R-12 so if you get 134 condensed with the available air-flow by using a more efficient condenser design, 134 will be more efficient (lower evap temp for the same heat-load) in the SAME evaporator size.
I've been judging C4 in NCRS for 10 years. A couple hundred cars. I'm certain the evap housings are identical for all the years. No way is the evap core "50% thicker". Plus it doesn't NEED to be, so it ISN'T.
The main difference for the condensors that the 134 is a "parallel flow" design, and the R-12 is fin and continuous tube.
Evaporator housings and cores are the same. There's nothing to gain with changing the evaporator. The condenser needs to be more efficient for 134 because 134 condenses at lower temperatures than R12. But 134 boils at a lower pressure than R-12 so if you get 134 condensed with the available air-flow by using a more efficient condenser design, 134 will be more efficient (lower evap temp for the same heat-load) in the SAME evaporator size.
I've been judging C4 in NCRS for 10 years. A couple hundred cars. I'm certain the evap housings are identical for all the years. No way is the evap core "50% thicker". Plus it doesn't NEED to be, so it ISN'T.
Last edited by Joe C; Apr 1, 2017 at 09:46 PM.
Drifting
Joined: Mar 2015
Posts: 1,275
Likes: 165
From: Utah
Good info.
I'm about to redo my ac for the second time next weekend.
Last year i flushed the system, replaced the hoses, and ran the original ac compressor.
It worked ok for a while, but the thing was noisy, i also cleaned up the pump before install and pulled out some black crusty crap.
Due to money and not trusting the compressor i did the conversion vs spending $100+ on r12.
This time around i have a much better flushing tool, better lines, and a brand new R4 compressor (4seasons).
I plan on doing the disassembly of the original compressor to see if i can find the source of the noise, however from what i read, it's garbage.
If it checks out i may try rebuilding it for fun.
I'm about to redo my ac for the second time next weekend.
Last year i flushed the system, replaced the hoses, and ran the original ac compressor.
It worked ok for a while, but the thing was noisy, i also cleaned up the pump before install and pulled out some black crusty crap.
Due to money and not trusting the compressor i did the conversion vs spending $100+ on r12.
This time around i have a much better flushing tool, better lines, and a brand new R4 compressor (4seasons).
I plan on doing the disassembly of the original compressor to see if i can find the source of the noise, however from what i read, it's garbage.
If it checks out i may try rebuilding it for fun.
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
Le Mans Master
Joined: Feb 2005
Posts: 6,485
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From: Clearwater Florida
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI