themack56

iTrader: (70)

well my old compressor was cracked and leaked some oil, so i changed with a used compressor that i know for sure was working, after i installed i refilled with r134a, is there something i missed?

SS#2906

iTrader: (53)

Did you refill it yourself with the cans from autoparts store? If so, maybe it's not full yet.

themack56

iTrader: (70)

yes i did, i cant fill anymore since the can gauge says its full

Full-Force

iTrader: (11)

how many cans? are you sure the compressor is coming on?

Benner

iTrader: (2)

You didn't pull vaccum on the system did you. That's most likely the problem. When you brake the system open by changing something, you almost always have to evacuate it as to get all the air and moisture out of it before you add the refrigerant. You'll probally have to take it to somewhere that does AC service and have them evacuate it and refill it.

themack56

iTrader: (70)

1 can, well when the car is on and i turn the ac on, my idle goes up a bit, so im guessing that means the compressor is on

Ls1Rookie

As quoted above do as told! You have to pull a vaccum otherwise it will never work right.

9000th01ss

iTrader: (10)

An LS1 F-body takes 1.5 pounds which is two 12 oz cans.

Your ac might blow cool with another can added but without evacuating it first it'll never get near as cold as it used to. And if enough moisture entered the system it could mix with the oil to form sludges and acids.

themack56

iTrader: (70)

well i just bough this ac vac pump, should i empty the system vac it and then fill it back up?

Benner

iTrader: (2)

yes. You need to get as close to 30 hg as possible and hold it there for a a couple minutes. I wouldn't reuse the stuff you pull out of it cause it'll be contaminated.

themack56

iTrader: (70)

ok cool, ill let u guys know what happens

9000th01ss

iTrader: (10)

Whats the CFM rating on the vacuum pump?

And you need to run it for several hours not a few minutes.

If you just took your AC apart to change a few things and put it right back together with a new accumulator, you might get away with 15 minutes on a vacuum pump. But you already ran it, and who knows how long it's been apart.

orangeapeel

iTrader: (18)

Moving to maintenance

2001WS6Vert

If you vacuum it you should add a couple oz. of pag oil that gets lost when recovering and vacuuming the system. A strong pump just needs to be on fifteen minutes, an average one a half hour.

9000th01ss

iTrader: (10)

It wasn't recovered and evacuation doesn't remove oil.

I'd be more concerned with how much oil was in the old compressor and how much was in the used on that was installed.

Actually a lot, but lets hope you get lucky.

themack56

iTrader: (70)

well the pump should be in this week, how do i remove the oil in the system?
does the pump do that as well?

Benner

iTrader: (2)

It should removed enough of everything but unless the refrigerant you put in contains the pag oil, you'll need to add it to the system.

9000th01ss

iTrader: (10)

I'll post up one last time about doing a mother ******* AC job right.

This is a basic 'I lost refrigerant' instructions.
If you tore up a compressor you condenser is most likely filled with **** and ruined too.

You need to disconnect the hoses from each component.

Compressors get drained.
Accumulators get replaced.
Neither ever gets flushed.
Evaporators get flushed.
Condensers get flushed.
Lines get flushed.
Orifice tubes get replaced.
All the o ring seals get replaced.
Flushing removes the oil and contaminates, this way you get the right amount of oil put back in. Too much oil is a problem and too little oil is a problem.
What oil, well some jackass keeps saying PAG.
OK go find PAG oil. You're going to see PAG 46, PAG 100, PAG 150.
An LS1 F Body takes 9 oz PAG 150. Easy to find on your own---look on the old compressor it says GM oil# XXXXXX, just google the part number.
Assemble everything correctly. Put some oil in the comp, some in the accumulator, some in the evap and cond.
Put oil on the seals before installing.
Don't leave the oil open, use it and put the cap back on. Once you put oil in the system have it closed up asap. Don't leave the caps off the accumulator until you're ready to connect the lines.
When it's all together leak check it. Do not use compressed air, use nitrogen with a regulator, add a trace amount of refrigerant if you plan to use an electronic leak detector. If you use soap bubbles it has to be for leak checking it can't be hand soap.
After the leak check Evacuate the system. Thats what the vacuum pump is for.
A VACUUM PUMP DOES NOT REMOVE OIL!
YOU CANNOT RUN IT ON A VACUUM PUMP FOR TOO LONG! I've run them for 24 hours on systems that have been open.
YOU CANNOT RUN IT ON THE VACUUM PUMP FOR 5 MINUTES!
YOU CAN NOT ACCURATLY MEASURE VACUUM WITH THE MANIFOLD GAUGE SET!
If you want to measure vacuum get a micron gauge. If you flush it right and leak check it right and evacuate it long enough you should not need a micron gauge.
Then weigh in 1.5 pounds of 134a.
Thats two 12 oz cans. You should purge the air out of the center hose when you get the can connected.
I've weighed the 12 oz cans before and they vary by an ounce very often.
(thats full can weight minus empty can weight).

If you cannot do it like this don't bother trying.
I've done this long enough to know what the books say, I know what people fresh out of their automotive AC class will tell you and I know what works in the real world.
And those are three entirely different sets of instructions and opinions.

Take your pick, waste your money, do it right. It's all up to you.