Carb'd A/C swap

[MitsuMax]

I have a 1988 mighty max 2.0 that I'm putting a/c on from an 89 model. (both are carbureted) I have all the lines cleaned up, new expansion valve ordered, and I have a few questions. I plan on getting my hoses converted into barrier hoses locally, since I'm doing a r134 conversion I have to get new O-rings and a receiver drier as well. Any of you order the kit from NAPA or do you have any suggestions on where to buy the retrofit kit? Will the drier be compatible with the r134? I have heard of Freeze12, has anyone ever used that stuff before? Thanks! :))

[pennyman1]

Check the posts from Recian - he just put one on a 2nd gen and talks about all the parts used

[iceman]

When you go to do the conversion before you put anything in the truck this includes all of the lines, the compressor, and evaporator you need to flush them out. They make a flush for it and someone at napa should know what you are talking about. The reason is that the oil from r-12 and r-134 when mixed turn acidic and will eat up the system. generally anything new is going to be designed to work with r-134 since you cannot get r-12 anymore, again someone at napa should be able to tell you if it was designed for r-134. I got my o-ring kit from oreily and haven't had any problems just be sure you put a good vacuum on it and let it sit to make sure there isn't any leaks and don't forget the compressor oil.

[pennyman1]

You can get away without flushing the r12 system if you use r134a with ester oil instead of the Pag oil ones, or use straight r134a and add ester oil to top it off. The best method is to flush it, Autozone should also have the flushing kit. Change out the expansion valve for one thats r134a compatible

[recian]

Anytime you buy a new dryer they're compatable with either. That's kind of industry standard now. Yours being pre-93 it's got the 2-screw line design instead of the bolt on lines. Make sure you get the right one. Mitsu purposely changed the designs of the dryers between r134 and r12 trucks to prevent cross contamination and a quick reference to teh system's contents. You'll have to buy a new dryer either way. I put a 91 system on a 94 truck so it got confusing looking for parts since my truck would be a r-134 truck but the donor was a r-12 system.