So, I currently have a new engine going in my B350 van and since the old AC compressor leaked, I ordered a used compressor to have the mechanic swap in during the engine swap.

My van must have been one of the last models to have r12, and maybe they changed mid-year, because the service manual refers to r134a and the new compressor I got is r134a too.

I also ordered new AC lines and a new gasket and o-ring kit. If I swap the r12 compressor for this r134a one and add the new line, can I start using r134a? I know the entire system is sort of specific to the refrigerant type, so I don't want to put this r135a compressor in and then have something else malfunction.

I'm also wondering what I should do to overhaul this used r134a compressor before I have it installed? Should I remove anything and clean/replace? Never worked on an AC system, so any tips would be much appreciated.

Thanks!

 

R134a.

You will need to replace the high and low pressure switches as well. Should be a kit available for just such an occasion, that will also come with the adapters for the pressure ports. (if the high side pressure port is on the compressor, won't need an adapter for that, since it is already R134a)

 

LOL. That must have been painful to read!

 

You will also need:
Fitting adaptors as stated
new filter drier
Flush ALL old oil out and add correct PAG oil for the 134a system, the oils are not compatable
all o rings on all connections-green
May need change expansion valve, put new any way, they are cheap
freon
Its not hard to do

 

Does look like the correct low pressure switch? high pressure switch? How about filter dryer?

Here's a pic of the new compressor, (is that the high pressure port?):

 

Thanks for the info fellas. I don't understand exactly what the high and low pressure switches are. I understand the rest of the system, and that mine uses a receiver/drier and expansion valve vs filter, orifice tube and accumulator, but what are the switches for?

 

Switches are for low or excessive pressures, Will cut off the compressor if to low or high.

 

Dig around over here a bit.
https://www.rockauto.com/en/catalog/...r+conditioning

Im not sure about the condition of your used compressor.

 

The high pressure port may be on your line, it usually is. That is a plug for internal repair and assembly. That compressor looks rather iffy to me. I replaced the one on my Escalade last year with one off Fleabay and it wasn't much for a kit with a new compressor, orifice tube and receiver/dryer. If you're going to this much effort, I'd go all the way and do it right. After flushing, your old condensor and expansion coils and such will work fine with R-134. I bought a '93 Dakota in '93 and they said if it needed a/c repair, they would convert it to R-134 as a matter of course.

 

Your high pressure port is usually on the line. That is a plug for internal repair and assembly.That compressor looks rather iffy to me. I replaced the one on my Escalade last year with one off Fleabay and it wasn't much for a kit with a new compressor, orifice tube and receiver/dryer. If you're going to this much effort, I'd go all the way and do it right. After flushing, your old condensor and expansion coils and such will work fine with R-134. I bought a '93 Dakota in '93 and they said if it needed a/c repair, they would convert it to R-134 as a matter of course.