Manager Forum

I am just checking to see what other shops do on converting R12 to R134. I have places around here that have just been getting those conversion kits from the local supplier and screwing on the fittings. The last conversion I did, I did the full replace compressor, drier, flush, new oil, and the guy has been loving it for over a year now. So how do other shop deal with it? Do you use the wuick conversion kits or do you do the flush etc.

Depending on the vehicle we will just put fittings on it and evac and recharge. Id say weve done 1000+ of these with little issues. If the a/c does nto work when it comes in you need to be aware of issues that were already present but you were unable to know about until you get the a.c operational. Those are the only issues ive seen. Like a leaking comp etc.

brianp87 wrote:Depending on the vehicle we will just put fittings on it and evac and recharge. Id say weve done 1000+ of these with little issues. If the a/c does nto work when it comes in you need to be aware of issues that were already present but you were unable to know about until you get the a.c operational. Those are the only issues ive seen. Like a leaking comp etc.

Same for us.

Ditto here

I usually replace the Rec/Dryer, then flush out the system and install the conversion fittings. On some there is a different orifice tube or setting on the cycling switch. That's about it. Very successful so far with no complaints.

I have even personally just used the kit on my little daily pos, and it has worked great. I have done them before and yes most worked great with no issues. I was just bringing this up since a/c season is upon us, and I had one in asking already. He was at the dealer and they quoted over $1000 to fix. I told him I had to see it first, but may be able to get by the cheap way.

I preety much have done the same as the others. I do replace reciever drier as Ric does also. One thing I've found is the refridgerant oil is critical to get right. I really helps get the cooler temps. We've done a few hundred or a thousand and rarely a problem unless it already had one.

We too evacuate for extended time, add proper amount of designated oil and recharge. Been working good for the last several years. The oil is important because mineral oil used in R12 systems won't move with R134.

Went to an A/C class several years back that was sponsered by four seasons co, and the instructor said that on cars that came with R12, when you are doing a compressor job and changing it to R134a, to put about 1.5-2 ozs of mineral oil in the compressor before installation and it will stay in the compressor and help to make sure it is lubed properly at all times. Said it is due to the fact that R134a does not carry mineral oil. I have done this since and have not had any problems with compressor failures. Of course this only applies to cars that came factory with R12....... Also when doing a compressor, I add oil to the compressor and stand it on its clutch for 15-20 mins to allow oli to seep in to the front seal area and help to insure it does not fail early. (Tip from same instructor). It must work cause the people at the parts houses say I have a much lower rate of compressor failure that most of the other shops around.....

liljoe wrote:Went to an A/C class several years back that was sponsered by four seasons co, and the instructor said that on cars that came with R12, when you are doing a compressor job and changing it to R134a, to put about 1.5-2 ozs of mineral oil in the compressor before installation and it will stay in the compressor and help to make sure it is lubed properly at all times. Said it is due to the fact that R134a does not carry mineral oil. I have done this since and have not had any problems with compressor failures. Of course this only applies to cars that came factory with R12....... Also when doing a compressor, I add oil to the compressor and stand it on its clutch for 15-20 mins to allow oli to seep in to the front seal area and help to insure it does not fail early. (Tip from same instructor). It must work cause the people at the parts houses say I have a much lower rate of compressor failure that most of the other shops around.....

Ive heard this before also the mineral oil will stay in the compressor it cannot be moved witht he r134a so it will still lube. Same with a aconversion any oil in there will still lube ith just cannot be transfered around the system. We also have a low rate of failure very few. We us bg oil in all a/c systems and whenI flush we use dura flush. We also use variable orfices which seem to actually help.

In going to AC classes the last number of years, mention is made of the variable orifice tubes. I have used several already and would say that they probably work better in the south where you fellows are. I didn't notice any difference than using the regular orifice tubes. I brought this up in one of the classes and the 4S instructor agreed with that idea.

Regarding oils. We add about 1oz of ER to every system. Energy Release, that is. Reduces friction, clings to metal and helps lower temperatures. Works very well for us.

Regarding AC compressor combacks, the local parts place told me recently that a high percentage of failed compressors can be traced to no oil being added to the system by the installer. Imagine that! So, we install a new compressor, accumulator, orifice tube, recharge with freon and do not add oil ------ equals a failed compressor.

Haven't done a conversion in years but i always replaced the dryer, extended vacuum, flush, new oil, orifice tube, and adjustable cycling switch. That was the basics, some vehicle models needed other work. It was a bit time consuming but i saw the results of the 39.95 retro kit jobs.

While we're on the a/c subject here i'll add the little know fact about the adds for refrigerant supplements. What your customers need to understand is just because it says on the box "approved by the Federal Government" and a lot of other crapolla doesn't mean it will work. It means that it will not effect the ozone layer. That's it, nothing more. You can get coyote piss licensed by the EPA but that's not going to cool off the vehicle. I've seen some that are using propane as a major ingredient.

steven kiser wrote: I've seen some that are using propane as a major ingredient.

Had a fellow several years back stop by trying to sell a "drop in" replacement for R12, can't remember the name of it, but I was looking at the lable and noticed it said "contains liquid propain gas" I asked the guy " ain't that flamable?" He said it is no more flamable then hair spray in a can..... asked him had he not ever used hair spray and a bic to make a blow torch????? He wasted no time leaving after that...

liljoe wrote:He said it is no more flamable then hair spray in a can..... asked him had he not ever used hair spray and a bic to make a blow torch?????

I forgot about the fun we had with them.

We offer all the options to customers from just changing ports to the full 9 yards. The oil is very important, the oriface tube also. I was taught that a piggy back condenser is needed, never done that one yet. Flush is very important and long vac time. Charge with 80% of capacity listed for r12. All rubber hoses are supposed to be replaced because the molecules in 134 are much smaller than r12 and can seep thru a good hose. Its all about how cool it will get and how long the system will last. There is my 3.5 cents