Converting R12 to R134

First off, I know that taking it to a shop and getting everything done is the best way to di this, but I don't have too much cash, and the 95+ temps are killing me....that and the girlfriend is gnawing my ear off for my always 'wanting to take the jeep' [1984 V6 2.8]

I bought a conversion kit with 30oz of refrigerant, 6oz of lubricant, o-ring conditioner, service port adapter, and charging hose w/ gauge.

Is there anything else I need? And the main question:

Does anyone out there know where to find instructions on how to do this (not neccessarily on my year) with pictures???

TIA Ed

Just as general knowledge, the kit you are referring to can be had at Wal-Mart and typically results in the compressor failing shortly after. The o-rings at any couplings should be replaced with those compatible with 134. You might be able to get away with the old o-rings without it leaking, but likely pinhole leaks will develop.

In addition, the A/C should be vacuumed and ensure that it holds it for around 30 minutes (this also will remove any moisture in the system-prevents compressor death) You could take it to a shop to have it vacuumed after YOU replace the o-rings BEFORE adding refrig.

Secondly, do you know if this compressor is even good? Turn on the A/C and jump the low pressure switch, the rad fan should come on and the clutch should engage. Do not run it for very long, since it sounds like the refrigerent (and oil) has leaked out of the system. If the pulley locks, turn it off and keep the A/C off and consider the compressor trashed.

OR, you could ignore everything I said and toss it in and see how long the compressor lasts.

(89CherokeePioneer)
Just as general knowledge, the kit you are referring to can be had at Wal-Mart and typically results in the compressor failing shortly after. The o-rings at any couplings should be replaced with those compatible with 134. You might be able to get away with the old o-rings without it leaking, but likely pinhole leaks will develop.

In addition, the A/C should be vacuumed and ensure that it holds it for around 30 minutes (this also will remove any moisture in the system-prevents compressor death) You could take it to a shop to have it vacuumed after YOU replace the o-rings BEFORE adding refrig.

Secondly, do you know if this compressor is even good? Turn on the A/C and jump the low pressure switch, the rad fan should come on and the clutch should engage. Do not run it for very long, since it sounds like the refrigerent (and oil) has leaked out of the system. If the pulley locks, turn it off and keep the A/C off and consider the compressor trashed.

OR, you could ignore everything I said and toss it in and see how long the compressor lasts.

Click to expand...

I am ASE certified for A/C repair and service, and you sir have it correct!!

It's alot more than what you think needs to be done. EVERY last molecule of R-12 must be removed before anything else can happen. Also any remaining oil in the system should be chamged as well to avoid failure....

I've repaired alot fo system where the owner has done the conversion themselves, none of then were pretty.....

Usually when the compressor dies and blows the case apart.....

Wow, thanks for the quick replies, and all the really good information. Also, some details on my jeep--if I turn the A/C controls on air comes out of all the vents, but temp. wise its like putting it to 'vent' mode. Don't know if that changes the diagnosis. Also, would you guys think it a good idea to have a shop vac out the system, and then do the recharge/replacement myself?? How much does this normally run?

Again, thanks for everything.
Ed

I personally would have a shop do the whole thing.

Their maybe more to the system that has failed or is failing, that you may not be able to do.....

Yes, it's more money, but it's worth it not to have the A/C compressor blow up on the freeway at 70 MPH....

ASE= Ask Someone Else

I just finished replacing my seized compressor. I changed all the seals out, and got a new drier. However, the steel nut on one of the lines tore up the aluminum threads on my condenser so I had to replace that as well. Cost me nearly $400 just buying everything. I have all the tools and my EPA 609 cert so I did it all myself.

Have a shop attempt to recover any remaining R-12 as a first step. I bought a venturi type vacuum pump from Harbor Freight that worked nicely.

Since you're asking for pictures, I'd suggest you consider doing the grunt work, like changing o-rings and such, and leave the charging to the shop. The pressures in the system are pretty critical. Too low and it wont cool. Too high and it may damage the system.

firefight343 said:

Wow, thanks for the quick replies, and all the really good information. Also, some details on my jeep--if I turn the A/C controls on air comes out of all the vents, but temp. wise its like putting it to 'vent' mode. Don't know if that changes the diagnosis. Also, would you guys think it a good idea to have a shop vac out the system, and then do the recharge/replacement myself?? How much does this normally run?

Again, thanks for everything.
Ed

Click to expand...

Either the clutch isn't getting power because of an electrical issue at some point, or much much more likely the refrigerent has leaked out and caused the low pressure switch to open.

I would have it discharged (there may be none in to discharge anywho) then replace the o-rings-then have a vacuum pulled on it. If the vacuum comes out okay with no leaks, then I'd replace the refrig+oil. I believe it's mandatory to replace the accumlator.

This is all assuming the compressor is good, if it's not a new one is upwards of $300 and a junkyard one is questionable.

I needed a new compressor so had a shop do the compressor and the conversion last year. Cost was around $700 but it cools pretty well now. I was afraid the R134 was not going to cool the XJs interior but I am happy and more importantly my wife is happy. So spend the money or lose your ear.

I would do it as a bussiness, but I lack the tools to do it.....

Pressures are pretty critical, to low is better than too high.

My first question is do you know what refrigerant is currently in there?

The OEM in 84 was R-12, but most R-12 systems (not all!) that old have been upgraded to R-134a already. The fittings are different on the compressor, and if it was upgraded it has the R-134a quick connect fittings on the compressor (and possibly an upgrade label on the compressor). If it is still R-12 , it has small threaded fittings on the compressor to hose connections, not quick connects. There are also service valves on their that may need to be opened to charge, drain or read system pressures.

To do it yourself properly you need gauges, gauge hoses and a vacuum pump, minimum, if you open the system!

If you open the system I always replace the high pressure hoses, and the filter / dryer (sometimes called an accumulator) and o'rings. I usually replace all the rubber hoses, especially in a R134a upgrade. Hoses are usually the first think to go bad, and leak, especially the Hight pressure hose, and the R-134a uses a special barrier hose that R-12 did not use.

You need to find out 2 things first, what refrigerant is (or was) in the system last, and why it leaked out (where) if it leaked out.

If you want to learn more about Doityourself Auto AC with pictures check out this website discussion group:

http://www.autoacforum.com/categories.cfm?catid=2

firefight343 said:

First off, I know that taking it to a shop and getting everything done is the best way to di this, but I don't have too much cash, and the 95+ temps are killing me....that and the girlfriend is gnawing my ear off for my always 'wanting to take the jeep' [1984 V6 2.8]

I bought a conversion kit with 30oz of refrigerant, 6oz of lubricant, o-ring conditioner, service port adapter, and charging hose w/ gauge.

Is there anything else I need? And the main question:

Does anyone out there know where to find instructions on how to do this (not neccessarily on my year) with pictures???

TIA Ed

Click to expand...

here we go again...

It may be worth checking around at some smaller corner garage style shops. I was trying to find a shop that would vac the system down for me so I could do the rest. I was surprised at how many shops don't have r12 equipment any more (even the stealership!). A few stops later I talked to a guy who said he would do a Freeze12 swap for $210 parts and labor plus tax. Apparently the F12 is a direct swap for R12 with a couple new valves. Check around.

My system has two aluminum hoses that run from the compressor to the left of the valve covers and back. It seems like each have two little valves about 2" from the (compressor) end (possibly pressure releases?) And at their ends, have very thin aluminum threaded caps--which if unscrewed, give access to a square peg (kinda like the back of a drill bit)

Again thank you all for your input...it's definitely not going unnoticed. I'll look around for a shop, but anything around $300 is better spent going toward new tires in my opinion...guess I'll just have to turn up that radio real loud, and tune her out in the interim.

Man I really thought it was just going to be one of those walmart fixes, where I could attach the can and have cold a/c (glad I kept the reciept).

The square pegs under the Aluminum cover are the shafts of a service valve. The side of the service valves should have small apx 3/8" threaded fitting, or a very large quick connected fitting (maybe attached to the small 3/8" threaded port). The square peg shaft of the service valve is rotated to open or close the valve. The small 3/8" fitting (the old R-12 fitting) has a reed style, tire valve in it that seals the port.

Saudade said:

Cost me nearly $400 just buying everything.

Click to expand...

Do you mind sharing where you got all the parts for $400? A quality compressor alone runs close to that.

TIA

Maz said:

Do you mind sharing where you got all the parts for $400? A quality compressor alone runs close to that.

TIA

Click to expand...

I got the Compressor (rebuilt SANDEN 508 with new clutch), condenser (new copper), o-ring kit, oil and some odds-n-ends from www.ackits.com. I bought the freon (R-12) on eBay.

I already had the manifold gauges, and vacuum pump.

Thank you Sir

I got my new condenser and new compressor from Ebay stores. I think completeradiator.com for the condenser, and I paid someone on Ebay about $120 for a brand new Sanden 508 from an inventory close out.