ac fix, vacuum and recharge questions

[team]

ok, got a few questions, but before I get blasted I have searched and read all the previous ac threads i could.
My system has a small leak and I put in about 1-2 cans a year and it works decent. Vehicle is a 1996 sport 4x4 4.0 ohv 168,000miles
Here are my questions

1. Does vacuuming down the system pull out any oil?
2. I see there is a seal kit and it looks like it has 10 o rings, where do all the o rings go? (do you have to unbolt any lines at the compressor, or just at the spring lock fittings)
3. I guess if i put on new o rings i need to get a new accumulator, if so, do they come with a new orifice or do you buy that separate?
4. Also, when you put in new refrig. can you just put it all in the low side with the can right side up? I saw on one of the help pages it was being put in on the high side upside down with the engine off, then put in on the low side right side up with the engine on.
5. If i put on a new accum. do I just drill a hole in the bottom, drain out the oil, measure, replace with the same amount and add extra 2oz. to this?
6. ALso, how do you put the oil in the best way? buy an injector, vacuum it down and put it in after a vacuum or what?
7. Is the orifice between a spring lock connector, or a cut out style?

That's all i can think of right now, obviously I am not the ac master so take it easy on me, but i want to try this so grace me with your knowledge. !

 

[Cobraguy]

(1) No. Contrary to popular belief, evacuating an a/c system pulls out absolutely nothing but air and moisture...and only moisture if you have it in a warm enough shop. At about 30 inches of vacuum, water boils around 55 degrees and the vapor can be evacuated. Not one spec of dirt or debris will be removed. However, oil can be lost through evacuating the freon or through normal leakage. That's why you measure the oil in the capture bottle and replace it.

(2) You replace the o-rings as necessary. If you take something apart, replace a component, etc. Lube with PAG oil before installation. (you don't unbolt the compressor lines unless you're replacing/repairing the compressor or lines)

(3) First, replacing the accumulator is no longer required by Ford in most cases. However, some compressor manufacturers require it. It doesn't hurt. Also, if you have had a compressor failure, you must replace it.

The orifice tube is not located in the accumulator. It is in the lower line of the evaporator.

(4) NEVER EVER charge on the high side with the engine running!! That side can reach 250 lbs pressure...and even higher. That means the can will see that pressure. BOOM! Always shut off the high side line prior to charging unless you are using a charging system that pumps the freon into the system. Your a/c system could care less what side you charge from. Since it's going through the accumulator first on the low side, there is no issue liquid charging. (holding the can upside down)

(5) You can just turn it upside down and catch the oil. But do a google search. There are a bunch of charts that will tell you how much oil to replace for each component you replace. If you flush the entire system, I believe the total system takes 7 ounces of PAG 46 oil. (double check that!)

(6) You can just pour it in the accumulator. They also make tools that will allow you to charge it with the freon or force it through the charge fitting. But be very careful you don't dump it directly in front of the compressor. Also, if you replace the compressor, most come with a complete system charge of oil in the compressor. Don't over charge your oil.

(7) You remove the line from the lower outlet of the evaporator (it's a spring lock connector) and pull the orifice tube from the evaporator side. You can try using a pair of needle nose pliers and grab FIRMLY and pull. If it won't come, you can buy a removal tool. Tool trucks, NAPA, carry it. Be careful...you could end up having to pull the evaporator if you aren't careful. But that's rare...and they even make a repair kit if it happens.

 

[team]

Just a few more questions for clarification, thanks for the above answers already they helped a lot.

1. So if I end up replacing an o ring or two should I put in some oil for it?
2. If so, do you put it in before you vacuum the system?
3. I saw a syringe looking oil injector, do i just shoot it in the low side after evacuating and before vacuuming?
4. And finally, I can just put all my refrigerant in the low side right side up?

Thanks!

 

[Cobraguy]

(1) No. Not unless you see evidence of oil leakage from the bad seal. Then it's kind of a crap shoot as to how much to put in. Look and estimate remembering a small amount of oil goes a long way.

(2) I would. You can add it anytime before you start the car and run the system, but I always put it in first.

(3) You can put it in anytime...even before evacuating (vacuum) if you want. Your vacuum pump won't pull it out.

(4) Unless you have a charging station that pumps the freon without the vehicle running, then all charging MUST go through the low side. On an Explorer, it doesn't matter if the can is up or down since the low side dumps into the accumulator.

 

[PDA1]

Which tube do I put the oil into the accumulator/dryer? The one connected to the Evaporator or the one going to the condenser?

Any idea how much oil I should put in the accum/dryer? I think I'm supposed to put 7 oz total into my 96 Explorer a/c system.

Thanks