changed ac compressor and refilled with r134a no cold air
#1
TECH Fanatic
Thread Starter
iTrader: (70)
Join Date: Oct 2005
Location: Los Angeles, California (818)
Posts: 1,219
Likes: 0
Received 0 Likes
on
0 Posts
changed ac compressor and refilled with r134a no cold air
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?
#5
TECH Apprentice
iTrader: (2)
Join Date: Nov 2007
Location: Delaware, OH
Posts: 376
Likes: 0
Received 0 Likes
on
0 Posts
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.
#7
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.
Trending Topics
#8
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.
#12
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.
#14
10 Second Club
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.
#15
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.
#18
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.
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.