Automotive Air Conditioning Information Forum

Just a question after the fact:
If I was not in a vacuum as I am now, where and how would I have added the 4 oz of PAG oil to the system?

I would have put 2.0 oz in the condenser, 1.5 in the evap, and 0.5 in the accumulator, this is assuming the comp already has its oil

Or, you could have put all the oil in the compressor, if it would fit. I believe that's the way GM does it at the factory.

I have seen where some suggest putting all 4 oz in the accumulator. Good or bad?

OK, Iguess what I got ain't gonna work. There seems to be something missing in the end of the hose. when I screw this onto the threade connector on the liquid line, don't I need the pin inside the end of this?

Yes, that end is supposed to have a valve core depressor in it. ?Chinese?

Putting all 4 oz into the accumulator would be a disaster, since the next device after the accum is the comp, most of that oil is gonna head to the comp and destroy it.

I am not sure where you are getting all this marginal advice from, only to come on here and have us overrule

There are too many wannabe ac 'experts' out there

It may help to focus on the direction of flow of refrigerant in the system, and to keep uppermost in mind that you want to always avoid slugging the comp with any kind of liquid. A liquid cannot be compressed, so if the comp tries to do so, it will internally grenade into a pile of junk.

Starting with the comp, the 134 enters in the gaseous state (as a low pressure gas) from the low side, is then compressed into a high pressure gas, travels next to the condenser, which condenses the high pressure gas to a high pressure liquid, which travels to the OT. The orifice allows high pressure liquid to greatly expand into a gas. It sprays the liquid 134 into the evap, whereupon it turns to vapor. This expanding gas absorbs heat (that very simply is the definition of any type of refrigeration, ie, an expanding gas absorbs heat). If it cannot absorb heat, then it cannot expand and there will be no cooling effect. In this case the heat is supplied to the high pressure liquid 134 by the evap, ie the gas in the evap absorbs the heat from the evap which is actually the heat from the cabin of the car. Next stop is the accum, which traps any leftover liquid 134 and allows it to boil into vapor, so as to keep liquid away from the comp, which is the very next device in line. This cycle continually repeats itself.

Focus on this route of travel and what is happening to the 134 at each step along the way.

Yea, POS, freakin pisses me off where this world has come to. Amazon POS. Ididn't want to spend a lot for this one tool, cost 40 bucks.
So, I thread it onto the threaded fitting, after getting the air out of the hose, and open the high side valve on gauge?

Without the depressor it is not useable

" and open the high side valve on gauge?"
If by this you mean open the high side handwheel on your MGS, then no. That will not accomplish anything.
As JohnHere states, the vacuum in the system will suck the oil into the system. You don't need the MGS for this at all

You spent a good amount of change on the Appion, so a proper oil injector is far less. It is difficult to do AC work without proper tools.
Suggest a reputable brand such as Yellow Jacket. They make all manner of tools, equipment, hoses, fittings, etc for the industry

OK, I got a high side quick adapter to inject the 4 oz of oil into the high side and am ready to pull another vacuum for an hour as Deroit suggested.
Do I leave both high and low side adapters from MSG connected to the connectors on car and open, and leave the yellow connected to the vaccuum pump and start pump and slowly open blue line on MSG only.