Air conditioning compressor question
Thread Starter
Burning Brakes
Joined: Aug 2000
Posts: 952
Likes: 0
From: Morgantown,WV USA
Air conditioning compressor question
Ok- I think I am making progress, but need a reality check on something. I purchased a reman. compressor with clutch and evacuated the system. I installed everything and charged it with my handy retro-fit kit to switch it to the 134 stuff.
The good news is the system holds pressure and blows cold. The bad news is that the new compressor makes noise when it runs. It makes a clanking sound at idle and the belt is loose (it bounces around and I plan to replace it). The strange thing is that if you increase the engine speed, the rattling sound goes away. Anything over 1200 rpms makes it disappear. When the compressor is off- its dead quiet.
What do you guys think- did Advance sell me a bad compressor or could the loose belt be causing it?
Thanks,
Dan
The good news is the system holds pressure and blows cold. The bad news is that the new compressor makes noise when it runs. It makes a clanking sound at idle and the belt is loose (it bounces around and I plan to replace it). The strange thing is that if you increase the engine speed, the rattling sound goes away. Anything over 1200 rpms makes it disappear. When the compressor is off- its dead quiet.
What do you guys think- did Advance sell me a bad compressor or could the loose belt be causing it?
Thanks,
Dan
Race Director
Joined: Sep 2002
Posts: 10,362
Likes: 5
From: San Diego - Deep Within The State of CONFUSION!
Why did you buy reman instead of new? but yea as Mark suggested you do need to put oil in the system if you didn't. If you do have the proper amount of oil in it, then the pump is no good.
Drifting
Joined: Jun 2005
Posts: 1,523
Likes: 1
From: grand prairie texas
Couple of things to check. Make sure your refrigerant charge is proper if you have too much refrigerant in your system it will but an additional load on your system. More than likely either your compressor belt is worn or the tension is not correct.
Thread Starter
Burning Brakes
Joined: Aug 2000
Posts: 952
Likes: 0
From: Morgantown,WV USA
The pump came with a small amount of oiul in it, plus the 134 stuff I used to convert it had oil in the cans. I put almost three cans in it and according to the content of the cans I put almost 4 ounces of oil in the system (it hold 5, but I read to use 80% of the capacity when switching to ester & 134).
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 28
From: Florida
Most quality new and rebuilt compressors have tags or labels on them or at least in the box that state the oil type requirements and most void any warranty if the right vscosity pag oil is not used. Not that ester will cause noises quickly, but there is a reason.
Check it.
If the system is overfilled with refrigerant or oil, then the compressor can be noisy and put a lot of extra load on the belt too.
Did you flush first? change the dryer?
Check it.
If the system is overfilled with refrigerant or oil, then the compressor can be noisy and put a lot of extra load on the belt too.
Did you flush first? change the dryer?
Burning Brakes
Joined: Jun 2008
Posts: 1,086
Likes: 1
From: Michigan
All of the above seems like good advice. The compressor works really hard and puts a good deal of stress on the belt. If the belt is fluttering when the compressor is running, check the belt tension. I know from personal experience that a loose belt can make for a compressor rattle. If a new belt with correct tension doesn't solve the problem then you have to go deeper into compressor issues.
Three cans sounds about right. If you didn't change the accumulator/dryer and blow out the evaporator and condenser you could have some old oil left in the system. PAG oil and the old mineral oil used in the R12 systems is not compatable. Ester oil is compatable with both the old mineral oil and the new PAG oil. I blew out the system and replace the accumulator/dryer to be sure all/most of the old oil was out. Just in case I left any behind I used the Ester oil.
Also the old A6 compressors used about 11 oz. of oil and the newer R4 compressors only need about 5 oz. so I hope you didn't overfill if you replaced an A6 compressor with an R4.
Three cans sounds about right. If you didn't change the accumulator/dryer and blow out the evaporator and condenser you could have some old oil left in the system. PAG oil and the old mineral oil used in the R12 systems is not compatable. Ester oil is compatable with both the old mineral oil and the new PAG oil. I blew out the system and replace the accumulator/dryer to be sure all/most of the old oil was out. Just in case I left any behind I used the Ester oil.
Also the old A6 compressors used about 11 oz. of oil and the newer R4 compressors only need about 5 oz. so I hope you didn't overfill if you replaced an A6 compressor with an R4.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
5 Best & 5 Worst Corvette Daily Drivers
Joe Kucinski
The Headlights of Every Corvette Generation Explained
Joe Kucinski
5 Best & 5 Most Overrated Corvette Track Packages of All Time!
Joe Kucinski
Every 2027 Corvette Engine Explained
Joe Kucinski
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Verdad Gallardo
10 Ugly Corvettes That We Still Kinda Love
Joe Kucinski
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
Thread Starter
Burning Brakes
Joined: Aug 2000
Posts: 952
Likes: 0
From: Morgantown,WV USA
Air conditioning compressor question
[QUOTE=08vycpe;1573631996]All of the above seems like good advice. The compressor works really hard and puts a good deal of stress on the belt. If the belt is fluttering when the compressor is running, check the belt tension. I know from personal experience that a loose belt can make for a compressor rattle. If a new belt with correct tension doesn't solve the problem then you have to go deeper into compressor issues.
What a difference a correct, new belt can make
The old belt was the wrong one and was a tad too long- it was just long enough that it was ay the end of the adjusting slot and was still a little sloppy.
A new, correct, belt was installed and the air blows ice cold and the new compressor is quiet as a mouse
I great "thank you" for everyone who advised me through this air conditioning rero-fit!
Dan
What a difference a correct, new belt can make
The old belt was the wrong one and was a tad too long- it was just long enough that it was ay the end of the adjusting slot and was still a little sloppy.
A new, correct, belt was installed and the air blows ice cold and the new compressor is quiet as a mouse
I great "thank you"
for everyone who advised me through this air conditioning rero-fit!Dan
Last edited by RedZR; Apr 10, 2010 at 01:48 PM.
