85 Chevy C30 a/c flush question
 

Just flushed evaporator and condenser with auto parts place flush. Blown out with clean air. How do you know if you got all the flush out? I googled a lot but no decisive answer. I don't want to leave it open for too long for the stuff to evaporate and let moist air in. I am going to flush with nitrogen before closing up for the vacuum. Will the vacuum pull out any flush residual? Any help appreciated. Installing new compressor also.

Re: 85 Chevy C30 a/c flush question
 

The solvent will evaporate. I blow both directions and let it sit a while then hit it again to make sure. Letting it sit is not an issue, evacuating should remove any moisture prior to pushing in some oil and refrigerant. Make sure you read the compressor box and instructions to get the proper amount of oil in the system. Some rebuilders just have assy oil in the compressor and others fill them up so you have to drain the compressor and measure what comes out for the total needed in the system. Then there is the whole thing of converting from R12 to 134a with the PAG oil and the different viscosities per Mfg. reccomendations

Re: 85 Chevy C30 a/c flush question
 

I'm putting in new Harrison R4. It had the right amount of oil but I drained and refilled it. Some people say to put all the remaining oil in the accumulator and some say to add 2 oz to accumulator, 1 oz to condenser and 1 oz to evaporator. What's your recommendation?

Re: 85 Chevy C30 a/c flush question
 

If I have the system apart then I'll measure out all that I need and pour it down different hoses or components. That way it is spread out through the system when I fire it up. The oil will settle through anyways, so I just help it out some. That way there is not a big blast of oil when the compressor starts doing it

Re: 85 Chevy C30 a/c flush question
 

Well, I have a new problem. It seems that I don't have an a/c fitting that will match the high side port on this 85 C30. I have multiple gauge sets with some adapters but nothing I have is small enough for this port. Iv'e never had this problem before with any Chevy's I've had. I was even going to screw a 134 adapter to it but it's too big, it won't even start to thread. Does anyone know what size that port is? I'm pretty sure it's the factory line. At my wit's end now.

Re: 85 Chevy C30 a/c flush question
 

Now I just found out that my new 4 seasons r4 compressor doesn't have oring ports but they gave me some metal encased orings with the it. Will they work with my old oring manifold? It says to torque them to ?nm and check the dimension between the manifold block and compressor, supposed to be like 1.2mm.

Re: 85 Chevy C30 a/c flush question
 

They give you different thickness o-rings because different manifolds have different offsets.

Re: 85 Chevy C30 a/c flush question
 

This compressor just came with one set. Delco 2724575 and 15-2720. GR9-222. I actually thought they were both the same so I don't know if I put them in their correct place, high or low port.

Re: 85 Chevy C30 a/c flush question
 

My old manifold is for the 2 orings that go into the grooves in my old compressor. The new compressor has no oring grooves.