I spent about $1,000 Summer before last getting my AC in tip top shape. Last Summer I had to charge it twice and now, it will only stay cool for a couple of weeks. Is there something that I can do as far as a leak / dye test or do I need to have it done by an AC specialist ? I am going to reak down and get it fixed again but not until I am 100$ sure it has no leaks. Anyone know where to get the high and low pressure lines for an older vehicle other than having them made ? I am aware of the leak posibillities at the fittings but was curious of the hoses as well. I will end up getting a new compressor, accumulator and orifice tube but wanted some advice from those that do this. I am almost considering making the conversion to R12 or whatever the newer freon is since I can add a can of that stuff from time to time for less than $5. as opposed to $30. a can.

Thanks fro the advice guys,

 

I am an air conditioning contractor in florida, but have converted my system over to R-134A and repaired a few family member's automotive A/C's. However automotive A/C's are not my specialty! I am assuming you have an R-12 system and It is costing alotta money to maintain? When you spent the $1000.00 summer before last, why did'nt you convert it then? The easiest thing you can do to locate a leak is the old fashion bubble test. Mix dishwashing soap and water 50/50 and start putting the solution on the fittings and look for bubbling. The sytem does not have to be running because on a 80 deg. day, assuming you have R-12, the pressure in the entire A/C system will be 84 psig. If the engine compartment is hot, the pressure will probably be higher. Just start putting it over all the fittings an the system and see what happens. As far as hoses go, they are still available at auto parts stores! I would recommend that you convert the system though to 134A and be done with it. I bet that you have what is called an azeotropic mixture of a refrigerant in your system like HOT SHOTS or COLD 12. These were made for a direct replacement for R-12 so you did'nt have to change oil and accumaloters etc. However these are a mixture blend and one tiny little leak will cause one part of the blend to leak out ( the part with the highest pressure first) and make the entire charge useless without the one part!! You can pick up a retro-fit kit fairly cheap and accumalators are really not that expensive, and get a new "o" ring kit to and change all your "O" rings, wet them with the new oil first. Oh yeah any leak in an air conditioning system will be accompanied by oil, if you have a fitting with alotta oil and dirt around it, that is a good starting point.
Good Luck.

She Ain't Revved Ti'll The Rods Are Thrown!
Al

 

Ouch, 1000bucks? I built my own hoses too cennect too a brand new sanden compressor and with the new compressor brackets and R-134A, new orface, it cost me a little over 500 bucks.
You don't need any conversion kits, you can just pump 134A in your system with no problems, it is pressured at 80% of R-12.

 

You cannot pump 134A into your system! You have mineral oil in your compressor that is not compatiable with the R-134A it will not lubricate properly and eventually burn out! It will work for a little while. That's why they retro-fit A/C system's to except the new refrigerant. $1000.00 is alot of money! It does not cost that much to bring it to a qualified shop and have them do the change over. Good Luck it's gonna get hot fast.

She Ain't Revved Ti'll The Rods Are Thrown!
Al

 

Alsair and the rest,

Thanks for the info. I am going to replace my compressor, dryer, orifice tube and anything that is causing my leak. I have little if no pressure in the lines now due to leakage so I have a question. What damage wiil it cause to the lines if I put air in there in order to find the leak since the components are going to be replaced anyway ? Will the input of air cause anything other than the components I am going to replace rust ?

Thanks again,

 

Who told you that, a saleman?

I and my dad have mixed oil from both in different conditions, and the oil mixes like it was made for eachother. He has been fixing ac for over 30 years and has mixed freon in countless autos.
Al that retro fit talk is just so part houses can make an extra buck

 

You can put air in the system, however it is not recommended due to the fact that compressed air has moisture in it and that will get into the A/C system i.e. evaporator & condenser coils and lines. Moisture in a A/C system is not good! If you have top quality air driers for compressed air system you can do it, however you have to do an incredible evacuation ( Pull the system into a vaccum to remove all air and moisture) before charging the system. A dry inert gas like nitrogen or C02 is used for pressure testing system's. Do not go above 150P.S.I. But to be honest with ya I went to 200 and the pin hole in the evap coil let loose, and well the good new's was I found the leak, bad news was having to replace the coil.

She Ain't Revved Ti'll The Rods Are Thrown!
Al

 

you can take it too a shop and they can pressure it with some freon, then use a leak detector.

 

Broncoroadkill, It is a known fact that the oil from a 12 system and a 134 system are non-compatible Mineral for 12 and ester for 134A. I am a licensed A/C contractor, Universal E.P.A certified, Have an associate's in H.V.A.C. and R been doing it for only 15 years. All that really does'nt mean ****! But I will keep doing what I'm doing. Just trying to give the right advice! I can't tell someone to do it the wrong way, I would be out of buisness!!

Al

 

good point, since I have been woking at autozone, I can't tell people this little known info.
But, if anybody feels exparimenta, my dad mixed the freons in his 86 F-150 and he sold it about 8 years later too my uncle and he still drives the truck too this day, and the ac works like a charm. My dad is the only one who has touched the ac since it rolled off the factory floor.

 

broncoroadkill is 100% correct 134a drops right into a r12 system, auto ac system that is , ive been a refrig. tech.10 yrs +. I am not a auto tech but experience with auto ac and reliable old school mechanics agree. The gentlemen contractor has been quoting to much from his school books and i believe he likes to try to impress people with tex-book horse****, no offence. Its been so long since ive heard the word azeotrop, any tech who resites that word instead of just saying mixed refrigerants loves to try to impress!!

 

Rock on brother!

I was also gonna say, When me and my dad restored the AC in my 82 bronco, I dropped in a brand new sanden compressor, w/ brakets, built all 3 brand new hoses, plus new orface. Also is using stock new acumilator, and pressor switch, that is built for R-12. We chrged it 80% of R-12 capasity with R-134A, because who can afford R-12? And that stock style pressor switch cycles perfectly.

Just a note, I highly reccomend replacing any stock compressor with a sanden unit, you will need new brakets and hose ends, but It worth it in the end. A motorcraft stock compressor reman was about 300 bucks, and that did note include the extra 150 bucks you have too spend too buy a new clutch assybly for the compressor. I spent 250 bucks on a brand new sanden and that includes the clutch, and pre oiled.

 

You go ahead and mix and match your refrigerant's and oil's. I am not going to get in a ****ing match with you about. I am sure you are one fine tech. I will continue to do it the right way! I would not go around telling people you can do that though, does'nt make you sound very credible. Was I trying to impress, hell no, don't even know these people and they don't know me. Just stating the facts!! By the way, you might want to break out your text books and re-read that horse-****! Just a thought.
Al

 

Chill bro. No need for flame wars.