ac advice please

[74challenger03]

so my friend put r134 in the system,he changed the hook ups for his gauges. Using the newer stuff will that eat up the seals in my system. Another friend said he could get the right stuff if i wanted him to.Ac didnt work because of bad evaporator so im changing that and before i fill it i would like to know. Also what oil should i be using in the ac system and can i blow out the old oil when i pull the evaporator out by using a compresser in one line and out the other? thanks

[74challenger03]

 

[Matt70]

Is this the system in your E body? It needs to be converted from R12 to R134. Not sure if it will hurt the seals but the oils are different. The dryer will need changed as well as the oriface tube/expantion valve and pressure switch. I doubt you will get all the oil out using compressed air.   

[74challenger03]

 a thead said change dryer put in green o rings and ester oil and good to go. Im going to put HOT SHOT in the system it is like R12. Yes it is for the challenger

[74challenger03]

thank you Matt70

[72cudamaan]

a thead said change dryer put in green o rings and ester oil and good to go. Im going to put HOT SHOT in the system it is like R12. Yes it is for the challenger

Be very careful with the r12 wannabee's. They can be very flammable.

[Matt70]

Good deal, R12 is out there but expensive and hard to find. Good luck let us know how it works out   

[7071 challenger]

If you can get R12, that is the best way to go. R12 systems uses mineral oil, but if you convert it to R134a, you will have to drain the compressor completely and refill it with Ester oil.To drain your compressor, you have to remove from the engine, remove the fill plug, and turn the compressor upside down.  You need nitrogen to flush your evaporator. Of course, you have to replace your drier, (my suggestion is,  perform your pressure/ leak test with an old drier installed, and install the new one just before you evacuate the system. Your drier is there to remove moisture from your AC system and the longer it is open to atmosphere, the faster you will ruin it). R134a can damage seals and hoses, bt it will take a long time to do so. Some people use MP66 refrigerant, but these can ''eat'' you conderser and aluminium parts. I wouldn't use HOT Stuff on mine. I read about it and they don't have very good reputation. If you cannot get R12, go with R134a.
Let us know the results

Robert

[spamtank]

 

[74challenger03]

thanks guys, my friend told me to pull the condencer and clean that also. Changing the o rings and buying new dryer and going with the r134. Was told i could use Freeze 12 has anyone used that? Putting ester oil in. Could not believe how easy taking the heat box out. Ordering the heat box seal kit from Roseville, do we get any discount from them?

[Matt70]

Yes Dave gives members a discount. On your order put your screen man in the comments section. You can post in his thread also that you are making a purchase to remind him.

[spamtank]

If you can get R12, that is the best way to go. R12 systems uses mineral oil, but if you convert it to R134a, you will have to drain the compressor completely and refill it with Ester oil.
Robert

I have a few cans of R12 I got from my uncle.  My AC doesn't work at the moment.  Is there a way to leak test the system before hand before I waste a can of R12, only to find out its got a problem somewhere else?

[Matt70]

You can look for oil around the fittings and on the condensor and evaperator, but the best was is to charge the system and use a "sniffer" to check for leaks. There are recovery machines to save the freon but don't think any shops would have one for R12.

[spamtank]

You can look for oil around the fittings and on the condensor and evaperator, but the best was is to charge the system and use a "sniffer" to check for leaks. There are recovery machines to save the freon but don't think any shops would have one for R12.

Would a "shop" even deal with R12 anymore?  Is R12 illegal or can they still charge a vehicle originally designed to use it, if someone were to have a few cans to provide?  Or would they confiscate it and turn me in to the authorities?

I don't believe I see any signs of oil leaking.  I think I'll try to find a shop that still has a guy around 60 or 70 years old working there, that might know how to deal with the stuff.  Last time I did any AC work was 25 years ago, with a cheap tool from the auto parts store.

Thanks for the feedback.

[7071 challenger]

You can look for oil around the fittings and on the condensor and evaperator, but the best was is to charge the system and use a "sniffer" to check for leaks. There are recovery machines to save the freon but don't think any shops would have one for R12.

Go to any shop that works in refrigeration and ask them to perform a leak test for you. They will put a small amount of refregirant, (r134, R22, ect...), and then, put pressure with nitrogen. Any leak detector cannot smell nitrogen, that is why they put a small amount of refrigerant before the build up the pressure with nitrogen. NEVER mix R134a and compressed air: the combination is explosive! By putting in a small amount of R134a, (vapor), you won' t dammage anything, because it will be in only for leak detection, you won' t run the A/C with that in the system. You can also use nitrogen only, and use refrigeration liquid soap to find the leaks. It works good, but it is messy. Once you have a leak free system, install a new drier, (I recommand perform the leak test with the old drier installed), and evacuate the system with a vacuum pump. For best results, change the oil in the vacuum pump before using it. The oil in that pump absorbs moisture, so, it will evacuate better with new oil. Also, do not believe your evacuation is done that when your suction gauge reach 30'' of vacuum. Your vacuum pump will be ''noisy'' when you start her up. After a certain time, (at least an hour), it will become quiet. That is a good indication of a good vacuum. When the pump is hooked to your system, (running), close the gauges handles and you will undestand what I mean be ''quiet''. If you have access to a Micron gauge, hook it to the vacuum pump. When it reads below 500 microns, your evacuation is excellant. Close the refrigeration gauges, hook up your freon can and fill it. If you have questions, feel free to ask.

Robert