Converting to R-134?

[Razorback1980]

Hey Matt...don't sweat the small stuff.

LOL...it's really not that complicated.

Here is the story...buy a fill line and it will hook to the ac fill valve and adapt it to your vacuum pump....local hardware will have fittings. If you remove the valve stem, you will lose the vacuum when you take the pump off so don't do that. Just hook a fill hose to it and to your vacuum pump and run the pump until you have removed all air and water vapor from the system. I am not at home and I can't remember where on my gauge I pull the vacuum to but I think it's 30" but you don't have to get to that number. That is the proper way although I've done it without pulling a vacuum at all...just won't last as long or cool as well. Shut the vacuum pump off and let it sit for a couple hours. If you still have vacuum, then you don't have a big leak and you should be ok to fill. Unhook the pump by unscrewing the vacuum line from the fill plug leaving the system in a vacuum state. If you have the double gauge setup, it has valves you can close. If you have a single fill hose, then remove from the fill valve. Put the can(s) of oil on there and suck them into the system followed by the freon. The vacuum will pull the oil in but you will probably have to start the car and turn the a/c on to get the freon in and get the pressure you need to check. How you change cans will depend on the fill hose you have, but remember, you don't want any air in there...only freon. Check the pressures on both the high and low side and shoot for the values I mentioned previously. Too little is better than too much. If your pressures on one side or the other are way off, then you need to do some more work...if not enjoy your ac. The only hard part is finding any leaks you may have....hopefully you won't have to worry about that but if you do, let me know and we'll try to explain the ways for that.

The oil is carried through the system by the freon, so you want to use an oil that is compatible with the freon. Pag for 134 or ester for R12...or caster for either.

I think they sell the flush (cleaner) where they sell freon. If you have the compressor off, you can just dump the oil out of it. If you replace the dryer, there are two remaining parts that need cleaned. The condensor and evaporator. I hook a compressor to a rubber hose and fill the rubber hose with flush cleaner and then blow it through the system to clean it.

I can't remember how much oil to put in the system but it may be on a sticker on the car. If not, I'll try to look it up....or your local auto parts store can tell you.

[HondaDustR]

OK, thanks! I'll have to look into it once I get some extra time. I'll let you know if I get stuck.

[mattdavis11]

De-natured alcohol works well as a flush.