I live in Texas, and for years I have heard "war stories" about how difficult and expensive it is to convert "old" (I don't know the exact gas they used, "RC-something or other"...) air conditioner gas to new. So difficult and expensive (I thought) that there was an illegal flow of vehicles heading into Mexico in order to get repaired, because it was cheaper to do that, rather than converting to the "new" gas.

But just the other day, my boss mentions that a conversion kit costs less than $50.00, and that it was possible for a marginally skilled person (hello ) to do it.

Amazing! Given that I have been driving around in 100 degree South Texas heat all summer, thinking that I was looking at either a $600 conversion or a trip to Mexico. My boss (who sold me the truck)

So now am I asking, Is this REALLY the "scoop"? I'm hearing that you can purchase these kits at just about any retail auto parts store (like Auto Zone).

If all this it true, how would I go about making sure I get the right parts, tools and instructions on how to perform the conversion.

Thanks in advance,

Billy.


'86 F-150 XLT
4-speed manual transmission
"in-line" 6 cylinder w/factory air conditioning

 

The kit in question is available at mostt parts stores and even some dept stores. There will be plenty of debate as to the merit of the kits. I have used several with good results, one on my F250, as well as numerous other vehicles. You will hear plenty of war stories here as well, I'm just relaying that I did fine with it for 2 years now on the F250, and several years on other systems. The kits have a additive in the oil that helps with compatibility on R-12 systems. In the early days of the kits they did not have the additive, so bad things happened.

 

Don't do a "cheapie", you're asking for early failure. Here is a link on how to do it right: http://www.forparts.com/techretrofit.htm . There are many others on the internet; Google "R12 to R134 Conversion", "R134A conversion" or the like. Above all you need to replace the accumulator/dryer with a new one that is compatible with R134A, replace the orfice tube with the R134A version, get as much of the old mineral oil out of the system as you can, and use a polyolester oil. You also ought to install a high pressure cutout switch on the compressor output (high side) to prevent damage from over pressure. Done right, your A/C will perform really well; I can't tell the difference in cooling capacity on my '83 F350. Done wrong and you may well end up with compressor failure and big bucks to recover.

 

Thanks for the link. It's given me a sense of what is going on. It seems the vacuum pump and the manifold gauge are going to be a bit beyond me. Are these tools something that one can rent ? They seem like they would be more expensive than simply paying a professional.

Also, there was some discussion about alternative coolants to R134. I just want a "standard" situation; nothing weird or exotic. I assume I should stay safe with 134. Also, I read a post somewhere from a guy that said that it would be best to simply "top off" a functional system if it is just a matter of a small leak. (I messed up the first post. My boss (who sold me the truck) said the air was working fine last summer, so I assume the only problem is the coolant is low.)

I thought R-12 was banned. Or at least hard to get, expensive and just generally bad. Is this true ?

And can I assume that a conversion kit is going to include the replacement Accumulater/Drier ? What kind of money are we looking at here ? Is it still in the $50.00 range ?

I was hoping the link to the conversion kit would include a list of parts, tools, instructions, etc... I tried Googling for some more of this type of information, but couldn't find much. Are these kits "general" or are they make/model/year specific ? Should I be searching for my F150 first, and then look for the conversion kits second, or is this a "one size fits all" situation ?

Thanks in advance,

Billy

 

Generally the cheapies are only R134A, some PAG or POL oil and some adaptor fittings. Accumulators are separate (fit individual vehicles) as is the HPCO switch, orfice tube, etc. There's a lot more info in some of my earlier posts (search Piffery1 in this Forum). I get all my conversion parts at Advance Auto Parts (locally) except for HPCO from J. C. Whitney's online catalog. Remember, if the system lost its R12 charge then there is a leak somewhere that needs to be fixed before evacuating and recharging. I think R12 is still available, at least it was in 2003; that might be the cheapest way to go @ about $30/lb. Takes 3 lbs if I remember correctly. The leaks I've found have mostly been o-rings and shraeder valves (don't replace with tire valves) and occasionly a compressor shaft seal. I bought all my R134A tools and vacuum pump on eBay at a fraction of new cost.

 

If you can, hold off on the conversion-a new coolant is being released for use next year that does NOT require retrofitting parts and pieces of the system. It cools as well as and is fully compatible with R12-and it is environmentally friendly like R134.

 

Moved to Cooling, Heating, Ventilation and A/C Forum.

 

I went to Advance Auto Parts yesterday and had a conversation with what seemed to be a qualified Mechanic (he was just hanging around...) and got a pretty good idea about how to convert my '86 F150 from R-12 to R-134.

Saw the kit; it has a guage included in it and the price was about $40.00.

The mechanic said that it was very important to make sure that the entire system was not only evacuated, but also flushed. And that only a qualified mechanic could do this. He said that it was because the oil that is used with R-12 is incompatible with the oil used with R-134. I think he also said that compressor damage could result if the system is not flushed.

I didn't open the box to the coversion kit, so I cannot say what the instructions recommend, but I do wonder how it is that they can sell a "conversion kit" to retail customers, if it is going to take a professional to do the job correctly.

Because of this, I am asking how accurate was this mechanic's opinion. Do I need to have the AC system professionally evacuated and flushed before being able to do a conversion ? Do other people fail to do this, and if so, how likely/often does damage occur to their AC system ?

Also, Advance had 3 AC "Driers" available in stock, priced at about $30.00.

So $40.00 for the Conversion Kit, $30.00 for the Drier... How much would a professional charge to do the whole thing himself ? Could it be cheaper ? Certainly seems like it would be safer and more convenient.

Also, how difficult would it be to find a professional AC technician to only evacuate and flush the AC system, so that I could do the conversion myself ? And how would that cost compare to having them do the whole thing ?

And I have a question about the quality of the conversion kit. Would a professional be using higher quality parts than what I would be buying Retail ?


Thanks in Advance,


Billy

 

If you do it yourself there are a few things that need to be done to ensure proper operation and life of the AC components. Depending on what oil comes with the kit, if it is Poly Alkyl Glycol or (PAG) it will not mix with the mineral oil used with R-12. If it is Ester oil then you might get away with trace amounts of mineral oil mixed in but not recommended. You will also need to change the hoses, dryer, high and low pressure switches, these can all trap oil and lead to contamination. The rest of the system will need flushed and cleaned real well. I know some will say that they didn't do all that and had no problems but I have seen to many lose a compressor within a short period of time. Even if you take it to a professional make sure they do all the work mentioned and not just throw in some kit. Cheaper, by no means will a professional be cheaper. To do it right you are going to look at probably 500 to 1000 dollars for a true conversion that will last and not ruin your system. Now there is supposed to be a new freon coming out that will be compatible with R-12 and can even be mixed as well as work with mineral oil. I do not know for sure yet if it is coming out next year or when, but I hear it will be soon.

 

If you can't rent or borrow a set of R134A gauges, a refrigeration vacuum pump (with fitting to match gauges), a leak detector, and an air compressor with a blow gun attachment then you'd be better off taking it to a GOOD shop. If your hoses were not leaking with R12 then they will in all likelyhood be ok with R134A (apparently the larger R12 molecules fill the pores in the hoses so the smaller R134A molecules can't get through). If you have any bad hoses, you need to replace them with the barrier hoses approved for R134A. Drain the mineral oil from the compressor and blow out the lines, condenser, and evaporator. If you use ester oil (POL) with the R134A you shouldn't have a problem and it's not necessary to flush with mineral spirits if the system doesn't have contamination from metal or dessicant particles. I've done conversions on several vehicles without problems, most recently about 3 years or so ago on my '83 F350. I used a Castrol #26242 Retrofit Kit, a red orfice tube, new accumulator dryer for R134A, and a High Pressure Cutout switch (HPCO) from J.C. Whitney's on-line catalog (to prevent over pressure damage in extremely hot temperatures). I also had to replace the inoperative thermostatic fan clutch and the fan belt on my truck. I evacuated and recharged with 85% of the original R12 weight as stated on the underhood label. With proper tools, some mechanical aptitude and reasonable care you should be able to do an excellent job that cools comparably to the original R12 system. OBTW, coat the o-rings lightly with refrigeration oil before installing.