Modern A/C swap from donor?

[Streetbu]

Different freons have different cooling needs. They don't always make a retrofit condenser for newer style freon in an older vehicle, but if they do, it helps the system work better overall.

 

[jlcustomz]

If talking about swapping an entire system, mounting a different ac compressor will be the least difficult part. Mounting a different condenser up front isn't that bad either, Fitting a different evaporator /heater unit with controls would be a huge task. Connecting vents & their controls would be another. Some with camaro, etc donors have swapped entire dash, part of firewall, wiring , etc with the LS, but you're not doing at same time anyways. Any of this is a huge amount of work. Again fabbing compressor mounts to engine would be the easier, not the harder. Just being honest here.

If keeping/refreshing the existing g-body evap unit & controls, you can't use the ls style compressors. G-body units kick the compressor into on & off cycles, where the new compressors have variable internals. These compressors will work for a while with g-body controls, but WILL eventually fail. Wish I had known that earlier with my LS swap done back in 2002'.

Another choice some have done for a complete factory retrofit is doing a trunk mounted rear unit setup. Suburbans, etc, have rear units, along with front.

 

[Supa.Slo.SS]

Hey, I understand where you're coming from. It's hard enough to pinpoint when you're actually able to do the LS swap, so why not have a working A/C system in the car in the meantime while you're gathering parts and putting money aside to buy the necessary mounts, fuel system upgrade, electronics, etc.
If you already have the basic R4 compressor/ system in the car now, I'm sure you'll be able to have it gone over and make it functional without breaking the bank.

Every works on my stock A/C expect no cold air. The car sat for about 10 years before I purchased it so I am not sure what could be wrong. Maybe just seals and a charge? Compressor clutch does engage but obviously doesn't stay on.

 

[Supa.Slo.SS]

Do you have factory air now?

yes I do. Everything is there and functional just doesn't blow cold air.

 

[Supa.Slo.SS]

If talking about swapping an entire system, mounting a different ac compressor will be the least difficult part. Mounting a different condenser up front isn't that bad either, Fitting a different evaporator /heater unit with controls would be a huge task. Connecting vents & their controls would be another. Some with camaro, etc donors have swapped entire dash, part of firewall, wiring , etc with the LS, but you're not doing at same time anyways. Any of this is a huge amount of work. Again fabbing compressor mounts to engine would be the easier, not the harder. Just being honest here.

If keeping/refreshing the existing g-body evap unit & controls, you can't use the ls style compressors. G-body units kick the compressor into on & off cycles, where the new compressors have variable internals. These compressors will work for a while with g-body controls, but WILL eventually fail. Wish I had known that earlier with my LS swap done back in 2002'.

Another choice some have done for a complete factory retrofit is doing a trunk mounted rear unit setup. Suburbans, etc, have rear units, along with front.

Thanks for the info. I guess I do not know enough about A/C's I figured fabrication would be the hard part and everything else would just swap in from the donor. So skipping ahead, once the LS is in it, what the correct way to get A/C?

 

[L92 OLDS]

yes I do. Everything is there and functional just doesn't blow cold air.

FYI…It a general consensus that R4 compressors are junk from the factory. Another GM failure. They leak Freon and sling oil everywhere. Look at the bottom of your hood at the compressor location and you’ll see an oil stain. I ran them for years with Oldsmobile engines. It was painfull to replace hood felt, oil and freon every few years. Now I run an LS with a Sanden compressor.

 

[81cutlass]

yes I do. Everything is there and functional just doesn't blow cold air.

If you have everything there just replace the O rings, the drier and orifice tube and either charge the system with R134a yourself or pay someone. Dad and I have done this to half a dozen R12 systems (and he has done it since the 90's on off highway equipment) and if the compressor has been sealed it's almost always fine. I have killed 2 compressors doing this but the compressors were shot anyways and sat exposed to atmosphere for over a decade.

The amount of parts that will swap to an LS from the stock R4 system is small. The cost to get the existing system working is small if the compressor is fine.

You can get the stock system working for under $100. If it dies quickly you are out $100 but it's cheaper than dumping $700 into redoing the entire system or adapting a sanden compressor onto it and then making lines and brackets that will get used for maybe 1-2 years.

 

[Longroof79]

I guess there's not a whole lot you can do with an R4 that's leaking at the front seal, aside from converting over to a Sanden compressor, etc.
What a freakin' waste of money. I thought I was doing the right thing by buying a new AC Delco R4 compressor. Looks like the Sanden conversion kit is on my to-do list. 🙄 I certainly wouldn't throw good money after bad by buying a new R4 paper weight.

 

[ELCAM]

Changing GM front shaft seals - Automotive Air Conditioning Information Forum

 

[Supa.Slo.SS]

FYI…It a general consensus that R4 compressors are junk from the factory. Another GM failure. They leak Freon and sling oil everywhere. Look at the bottom of your hood at the compressor location and you’ll see an oil stain. I ran them for years with Oldsmobile engines. It was painfull to replace hood felt, oil and freon every few years. Now I run an LS with a Sanden compressor.

Thanks for the info. Hence, my hesitance to spend money on the current system.