I am planning on converting this truck to 134a. I have a new accumulator, compressor, lines, FOT (red), and new o-rings. I plan on installing the new parts, and having a tech charge and check it. I get conflicting info on oil. Some say Pag 46 and others say ester. An online chart says I need 10 oz. in this system. How much in the compressor, and do you just distribute the rest in the other components? Will replace all o-rings with the green ones. Do they need to be coated with oil when installed? Also, I will be doing a thorough flush before I install the new parts. Any input would be greatly appreciated.

 

I use Chapstick on the orings.
Don't worry about the oil. The AC guy will add the amount when he charges the system AFTER he has evacuated the air from it and tested for leaks.

 

The compressor already has oil in it usually - does it say what kind? I use Ester on my conversions since it is compatible with both R134a and R12.

 

The compressor I bought came empty.

 

I just converted my 92 F-250 to R134a. Vent temps are cold enough to sting your arm.

When adding a new compressor, you do need to add oil. Don't allow it to cycle dry. My compressor was still operational, so all I did was pull it and "flush" it with new ester oil by draining the old oil out, adding new oil, cycling the compressor by hand about 12 times, and then dumping that oil back out. I did that three or four times. Pag oil doesn't mix, I would recommend ester, unless you are replacing the evaporator core and condenser as well, even if you flush, just to be safe. Measure the oil that comes out of the compressor and add that amount to the new one, if the new one didn't come with instructions telling you a correct amount. If you get two and a half oz, maybe round up to three.

The two parts you have left in the system to flush are the evaporator and condenser cores. What are you planning on using to flush them? Whatever it is, make sure you have lots of compressed air. All of the flush needs to come out. Blow air in one end of the core and place your thumb over the other and pop your thumb on and off. This allows pressure to build up and it should help blow that flush through. Be smarter than me and use gloves .

Do you have the fs6 compressor? I put three in the compressor, two in the new accumulator, three in the evaporator core, and two in the condenser, totaling 10 oz. The oil will go through the system. If you want to add some of the oil by can, that's fine, but I wouldn't go over the recommended amount for the system. Excess oil takes place of refrigerant. By the way, if you have the fs6, there isn't a drain plug. You add it to the ports where you connect the refrigerant hoses.

The o-rings do need to be coated with oil. Never heard of using chapstick, however if UNTAMND has had success with it, it might be a handy way to lubricate them. If you choose to use oil, use the same you used for the rest of the system.

Make sure the tech adds some uv dye to the system.

Anyone is welcome to correct me if I'm wrong, these are just some of the steps I took when I did mine not all that long ago. So far, so good. It's been over 100 here and the cab of the truck has been ice cold .


Edit:
I actually used this link to figure out the quantity of oil for each component-

http://www.google.com/url?sa=t&rct=j...48705608,d.cGE

 

Depending on the type of oring and type of oil, you can either contaminate the system, or rot the orings. Chapstick works great as a lube and doesn't harm any oring or rubber type.
I've always just had the guy doing the AC charge put the oil in. But as long as you tell the guy you've already done it, and he doesn't over do it, you should be fine. But they may not give you a warranty on it. No idea though.

 

Oh, I wasn't disagreeing with you on that, that's a good idea.


On a fresh compressor, though? I can't imagine spinning anything at that speed without lube. You're right, you should tell the tech everything and anything you did to the system, however I doubt any warranty will be implied, as he is doing 90% of it himself.

 

Only put a new compressor a few times, but yeah, bolt it all in with no extra attention to the pump. I guess no one ever advised me to put my own oil in before assembly. The oil and refrigerant is going into the suction side of the pump anyway so I kinda figured it would be in the line ready to be immediately sucked into the pump once it got filled enough to kick on the pump.
Ill ask my guy what he does normally on a complete system upgrade the next time I see him.

 

Well, that all makes sense. If you don't mind and it's not too much trouble, could you let us know what he says? I have another vehicle to do in the not-so-near future (needs lots of other work first) and if there is a better way, then I'm all ears.

 

Thanks for the posted help. I got things together and working, sort of. I need to get a little more info. Thanks again.