A/C Compressor?

So 2 years ago I put a new compressor (from autozone) in and it has run fine/cold since then. The last few weeks Ive noticed my compressor cycling on/off a bit...now it doesnt run at all. Put a gauge on it and there was zero pressure! So added refrigerant and now the compressor just cycles on/off, wont stay running more than 5 seconds. Pressures are weird...70LS when running and about 60-80 on the HS. I pulled a vacuum...well tried....it wouldnt pull more than 26-. Once the vacuum was off pressure went to zero within seconds. Once filled up with some refrigerant I drove about 25 miles and it was completely empty then.
So is my compressor shot? Wheres my leak though...used a "sniffer" around the compressor and didnt see anything....also put uv dye and dont see anything. I peaked in the Evap core and looks dry.
Pulled orifice tube and did find some gray particles but not a lot....

So 2 years ago I put a new compressor (from autozone) in and it has run fine/cold since then. The last few weeks Ive noticed my compressor cycling on/off a bit...now it doesnt run at all. Put a gauge on it and there was zero pressure! So added refrigerant and now the compressor just cycles on/off, wont stay running more than 5 seconds. Pressures are weird...70LS when running and about 60-80 on the HS. I pulled a vacuum...well tried....it wouldnt pull more than 26-. Once the vacuum was off pressure went to zero within seconds. Once filled up with some refrigerant I drove about 25 miles and it was completely empty then.
So is my compressor shot? Wheres my leak though...used a "sniffer" around the compressor and didnt see anything....also put uv dye and dont see anything. I peaked in the Evap core and looks dry.
Pulled orifice tube and did find some gray particles but not a lot....

Put it back together and recharge with oil and R134a and leak dye.
Then go over the compete system.
All hoses and compressor and condenser and evaporator and dryer with sniffer and leak dye light.
Also look for oily spots.

So 2 years ago I put a new compressor (from autozone) in and it has run fine/cold since then. The last few weeks Ive noticed my compressor cycling on/off a bit...now it doesnt run at all. Put a gauge on it and there was zero pressure! So added refrigerant and now the compressor just cycles on/off, wont stay running more than 5 seconds. Pressures are weird...70LS when running and about 60-80 on the HS. I pulled a vacuum...well tried....it wouldnt pull more than 26-. Once the vacuum was off pressure went to zero within seconds. Once filled up with some refrigerant I drove about 25 miles and it was completely empty then.
So is my compressor shot? Wheres my leak though...used a "sniffer" around the compressor and didnt see anything....also put uv dye and dont see anything. I peaked in the Evap core and looks dry.
Pulled orifice tube and did find some gray particles but not a lot....

when I do this repair this is how it goes . the system is cleaned with cleaner. then blown out with an air compressor until all gray material is gone. the seals ,orifice . and filter dryer are replaced.

then I vacuum the system and check for leaks. when installing the PAG 150 oil I at this time use leak detector.

the leak if you suddenly lost cooling is most likely the condenser got hit with a rock . could be the high/low ac pressure ports are leaking. especially the high side.

need a black light with the leak detector but since you have a big leak it should not be that hard. with your vehicle I would use nitrogen pressure of about 120 psi and then spray down the ac components looking for bubbles.

I agree....find the leak.....just add 134a, so you have a static pressure of 70psi on both sides,,,,,then spray a soap solution, everywhere externally.....if nothing it has to be the evaporator...

I agree....find the leak.....just add 134a, so you have a static pressure of 70psi on both sides,,,,,then spray a soap solution, everywhere externally.....if nothing it has to be the evaporator...

So I filled it again with some more dye and refrigerant. I determined the leak is the compressor, in front of the clutch. It leaks so much that within literally 5-8 minutes the compressor loses so much refrigerant it stops coming on and ultimately pressure is zero!
Can someone confirm a part number for me, the genuine GM part#...its a 03 1500 5.3. is it 89024882 / 15-20940? Im definitely not buying an autozone cheapo again.

Was the AZ compressor rebuilt or brand new?
Is there any warranty left on it?

I do not see a year make or model or engine or VIN no.

Go to your local parts place and see if they have a brand new not rebuilt compressor or check with your local dealer with your Vin no.

So I filled it again with some more dye and refrigerant. I determined the leak is the compressor, in front of the clutch. It leaks so much that within literally 5-8 minutes the compressor loses so much refrigerant it stops coming on and ultimately pressure is zero!
Can someone confirm a part number for me, the genuine GM part#...its a 03 1500 5.3. is it 89024882 / 15-20940? Im definitely not buying an autozone cheapo again.

if you have a receipt or they may have your transaction with your telephone # see if they will take care of this they are usually good about these things . where the shaft seal was defective that would not be something you did wrong.

now if the internal valves got damaged because the system was not cleaned properly that would be a problem .

if you have a receipt or they may have your transaction with your telephone # see if they will take care of this they are usually good about these things . where the shaft seal was defective that would not be something you did wrong.

now if the internal valves got damaged because the system was not cleaned properly that would be a problem .

Do you guys think this a "real" condenser? Looks like a good price for a close to OE condenser. Im going to change the condensor since its an 03 with 165k miles on it. Just dont want something thats junk. Is AC Delco the same as what the truck came with?

http://www.ebay.com/itm/ACDELCO-OE-SERVICE-15-63666-A-C-Condenser-/350842483425?pt=Motors_Car_Truck_Parts_Accessories&hash=item51afd772e1&vxp=mtr

Do you guys think this a "real" condenser? Looks like a good price for a close to OE condenser. Im going to change the condensor since its an 03 with 165k miles on it. Just dont want something thats junk. Is AC Delco the same as what the truck came with?

http://www.ebay.com/itm/ACDELCO-OE-SERVICE-15-63666-A-C-Condenser-/350842483425?pt=Motors_Car_Truck_Parts_Accessories&hash=item51afd772e1&vxp=mtr

so the condenser has a leak ? I thought you had a bad compressor seal ?

so the condenser has a leak ? I thought you had a bad compressor seal ?

The condenser doesnt leak...just figured with the mileage and age and to ensure a clean system I would replace it.

The condenser doesnt leak...just figured with the mileage and age and to ensure a clean system I would replace it.

no that is not necessary. a waste of you money.

I would buy an air compressor rather that get a new condenser . then after you use the flush blow out the ac system components.

since the seal blew out the system should be pretty clean. now if you had a compressor failure , that was with a seizing condition you would need to be very though with the flushing and blow out of the system for metaL that will damage the compressor and get caught in the orifice. the filter dry still should be replaced with the compressor replacing .

no that is not necessary. a waste of you money.

I would buy an air compressor rather that get a new condenser . then after you use the flush blow out the ac system components.

since the seal blew out the system should be pretty clean. now if you had a compressor failure , that was with a seizing condition you would need to be very though with the flushing and blow out of the system for metaL that will damage the compressor and get caught in the orifice. the filter dry still should be replaced with the compressor replacing .

So all done....new condenser, flush the system, new dryer, orifice tube. Put a Denso/AC Delco compressor in. Pulled a vacuum for 2 hrs.
Only issue that occurred was when I filled the system with refrigerant my scale was messed up at the end. The digital display got funky.
My truck calls for 1.6lbs. My starting weight/tank shows 33 05.50 (my scale shows first 2 digits as lbs and last 4 as ounces. So to me my ending weight should be 31 45.50. My scale got funky and I couldnt read it perfectly, see attached. Did I add enough/too much? After all this work I want the right amt of refrigerant in it.

So all done....new condenser, flush the system, new dryer, orifice tube. Put a Denso/AC Delco compressor in. Pulled a vacuum for 2 hrs.
Only issue that occurred was when I filled the system with refrigerant my scale was messed up at the end. The digital display got funky.
My truck calls for 1.6lbs. My starting weight/tank shows 33 05.50 (my scale shows first 2 digits as lbs and last 4 as ounces. So to me my ending weight should be 31 45.50. My scale got funky and I couldnt read it perfectly, see attached. Did I add enough/too much? After all this work I want the right amt of refrigerant in it.

Cant get the photo to upload , anyways looks like the ending weight is 31 05.0

Cant get the photo to upload , anyways looks like the ending weight is 31 05.0

So I guess I put 2lbs in instead of 1.6.....should I let some out...start over?

I would put gauges on it and see if the high and low side pressures are within their acceptable range, based on ambient temperature. If too high, some needs to come out. If not, I'd let it ride.

I would put gauges on it and see if the high and low side pressures are within their acceptable range, based on ambient temperature. If too high, some needs to come out. If not, I'd let it ride.

Ok I didnt want to mess around....so I recovered the refrigerant and then added it again and put in 1.6 exactly. Now my hopefully final question for this project. Is it normal for the compressor to cycle on and off? Its about 68 degrees out today. I thought the compressor should stay on being the a/c was at the coldest setting....

Ok I didnt want to mess around....so I recovered the refrigerant and then added it again and put in 1.6 exactly. Now my hopefully final question for this project. Is it normal for the compressor to cycle on and off? Its about 68 degrees out today. I thought the compressor should stay on being the a/c was at the coldest setting....

with 68 deg f you will have the cycling. test it out @80deg F doors open fan on max Idle 1500-1800 rpm.

low side should be 40-45 psi. high side about 290-325 psi. .

with 68 deg f you will have the cycling. test it out @80deg F doors open fan on max Idle 1500-1800 rpm.

low side should be 40-45 psi. high side about 290-325 psi. .


Ok...I'm back..lol...so today was driving and turned on my a/c and the air was hot. I smelled rubber, realized a/c belt was burning. Looked under hood and saw sparks flying out of clutch! I think the new compressor blew!
The Denso compressor (ac delco) included a booklet that the compressor came with 7oz of oil and to adjust accordingly. My truck seemed to call for 8.6ozs or so. I added 2oz. Could it be the new compressor didnt really come with oil in it? Do most Denso come dry?

Ok...I'm back..lol...so today was driving and turned on my a/c and the air was hot. I smelled rubber, realized a/c belt was burning. Looked under hood and saw sparks flying out of clutch! I think the new compressor blew!
The Denso compressor (ac delco) included a booklet that the compressor came with 7oz of oil and to adjust accordingly. My truck seemed to call for 8.6ozs or so. I added 2oz. Could it be the new compressor didnt really come with oil in it? Do most Denso come dry?

what is normally done is you drain out the compressor oil if any in it. then you add the correct amount of pag 150. which is about 8-10 OZ. you put a few in the compressor, in the filter dryer ,,and the evaporator. also after you place the connections to the compressor you rotate the compressor so as to lube the compressor, then complete the install.

I would never use the oil that was in the compressor when shipped. also these are usually under a vacuum when shipped. some oil may be in them to prevent corrosion issues.

now if you flushed the system then which you should have then you would need to add the proper amount of pag 150 for proper operation. you cannot get 8-10 OZ of oil into just the compressor . get another one and see how much oil was put in . I doubt 7 OZ.

with low oil the compressor will get real hot then lock up. snap the clutch off or break the belt idler etc.

If you are just replacing the compressor......

Remove the old compressor, and drain out the oil in the compressor, and measure it......

Rule of thumb is, if less than 2.0 oz came out of the old compressor, you add 2.0 oz of pag......if you collected more than 2.0 oz of oil out of the old compressor, add the same amount collected to the new compressor.....


some compressors come with oil, some don't....if there is oil in it, empty it completely out and discard.....add the amount based on what was removed from the old compressor.....

If you are just replacing the compressor......

Remove the old compressor, and drain out the oil in the compressor, and measure it......

Rule of thumb is, if less than 2.0 oz came out of the old compressor, you add 2.0 oz of pag......if you collected more than 2.0 oz of oil out of the old compressor, add the same amount collected to the new compressor.....


some compressors come with oil, some don't....if there is oil in it, empty it completely out and discard.....add the amount based on what was removed from the old compressor.....

When the new compressor comes I will drain out the oil and see whats inside there, the paper included said 7ozs but as you guys say thats really impossible to hold that much! Very curious.
Should I install one of those inline filters, if so wheres the best location to cut the line?

I totally disagree with the statement the compressors cannot hold the entire system oil charge. I worked in a compressor factory- all the oil for the entire system goes out the door with the compressor to the assembly plant to be installed in a dry system. I was an engineer and went to almost all north american assembly plants and saw this first hand with all the competition's compressors- so please don't tell the OP that a compressor can't hold the entire system oil amount. It was back in the 70's that assembly plants would add the oil to the systems- then when one would burn up- the compressor people would blame the assembly plant for "forgettiing to add oil" The problem was solved by making all compressor manufacturers supply the necessary system oil in the compressors- so that the assembly plant could no longer "forget the oil" - been that way for 40 years now- also no one "rotates those compressors 10 times" prior to compressor start-up- imagine that!
If a system has a rear system- the assembly plant does add the 3 additional ounces of oil.

Ok...I'm back..lol...so today was driving and turned on my a/c and the air was hot. I smelled rubber, realized a/c belt was burning. Looked under hood and saw sparks flying out of clutch! I think the new compressor blew!
The Denso compressor (ac delco) included a booklet that the compressor came with 7oz of oil and to adjust accordingly. My truck seemed to call for 8.6ozs or so. I added 2oz. Could it be the new compressor didnt really come with oil in it? Do most Denso come dry?

The 8.6 OZ. specs for your AC system is for the hole system. NOT JUST FOR THE COMPRESSOR.

Rule of thumb is 2 OZS. oil for compressor. 2 condenser and 2 evaporator and 2 dryer.
Total 8 for complete system.

What did you do about oil on the first compressor?

If it had 7 oz in it and you added a couple. your first compressor replacement would be 7 oz over full and if you done same on second compressor replacement you would have 7 oz more over full with over 20 oz in system.

You only hope no is to flush the complete system.
Drain the replacement COMPRESSOR AND ADD CORECT OIL CHARGE FOR YOUR SYSTEM.

The 8.6 OZ. specs for your AC system is for the hole system. NOT JUST FOR THE COMPRESSOR.

Rule of thumb is 2 OZS. oil for compressor. 2 condenser and 2 evaporator and 2 dryer.
Total 8 for complete system.

What did you do about oil on the first compressor?

If it had 7 oz in it and you added a couple. your first compressor replacement would be 7 oz over full and if you done same on second compressor replacement you would have 7 oz more over full with over 20 oz in system.

You only hope no is to flush the complete system.
Drain the replacement COMPRESSOR AND ADD CORECT OIL CHARGE FOR YOUR SYSTEM.

So I put the new compressor in. Flushed all the lines completely, new dryer/accumulator. I added a few ounces more than it called for to be "safe". Any drawbacks to doing having a little too much oil or will the excess pool in the accumulator? Thus far air is cold and compressor is quiet.
The compressor did come with oil in it, and the tag says 7ozs, its the same Denso compressor I got last time. Makes me wonder how the heck the 1st one blew if it had all that oil in it to begin with and I added 2 ozs=9 in total then.

So I put the new compressor in. Flushed all the lines completely, new dryer/accumulator. I added a few ounces more than it called for to be "safe". Any drawbacks to doing having a little too much oil or will the excess pool in the accumulator? Thus far air is cold and compressor is quiet.
The compressor did come with oil in it, and the tag says 7ozs, its the same Denso compressor I got last time. Makes me wonder how the heck the 1st one blew if it had all that oil in it to begin with and I added 2 ozs=9 in total then.


I would have drained/removed the compressor oil and added the PAG 150 to the correct amount which is about 9 oz. what oil did the compressor come with any way ?

If there is different oil in the compressor then you can/will have problems.

So I put the new compressor in. Flushed all the lines completely, new dryer/accumulator. I added a few ounces more than it called for to be "safe". Any drawbacks to doing having a little too much oil or will the excess pool in the accumulator? Thus far air is cold and compressor is quiet.
The compressor did come with oil in it, and the tag says 7ozs, its the same Denso compressor I got last time. Makes me wonder how the heck the 1st one blew if it had all that oil in it to begin with and I added 2 ozs=9 in total then.

To much oil.!!!!!!!!!!!:sarcasmsign:
Like we have been trying to tell you.
With a compressor replacement when the system is not flushed.
You drain new/replacement compressor and just add 2 oz correct oil.
When replacement compressor has 7 oz oil and you add 2 or more.
You have a lot more in system than in can digest.
Just like over eating. you are going to get a big belley ace.:sarcasmsign:

The 8.6 OZ. specs for your AC system is for the hole system. NOT JUST FOR THE COMPRESSOR.

Rule of thumb is 2 OZS. oil for compressor. 2 condenser and 2 evaporator and 2 dryer.
Total 8 for complete system.

What did you do about oil on the first compressor?

If it had 7 oz in it and you added a couple. your first compressor replacement would be 7 oz over full and if you done same on second compressor replacement you would have 7 oz more over full with over 20 oz in system.

You only hope no is to flush the complete system.
Drain the replacement COMPRESSOR AND ADD CORECT OIL CHARGE FOR YOUR SYSTEM.

From what I found online my truck takes pag46 oil...its a 03 silverado 5.3....

To much oil.!!!!!!!!!!!:sarcasmsign:
Like we have been trying to tell you.
With a compressor replacement when the system is not flushed.
You drain new/replacement compressor and just add 2 oz correct oil.
When replacement compressor has 7 oz oil and you add 2 or more.
You have a lot more in system than in can digest.
Just like over eating. you are going to get a big belley ace.:sarcasmsign:

I did flush the entire system, condensor, evap core, new drier. So it had zero oil to start. Last time I added 2 ozs since the compressor came with 7 ounces. This time I drained some oil out of the compressor, turn it over...but didnt / realize that I shouldve spun the clutch to get the rest out. The oil was clear/no dye. I then added a total of 7-8oz to the system. Would mixing different weights of oil really cause problems?

I did flush the entire system, condensor, evap core, new drier. So it had zero oil to start. Last time I added 2 ozs since the compressor came with 7 ounces. This time I drained some oil out of the compressor, turn it over...but didnt / realize that I shouldve spun the clutch to get the rest out. The oil was clear/no dye. I then added a total of 7-8oz to the system. Would mixing different weights of oil really cause problems?

looks like the denso compressor does take the low viscosity oil PAG46. the HT6 compressor uses the PAG 150 high viscosity oil. this change was made 2002/3 model years so read the sticker under the hood to cross over the GM number to the correct oil that was used. but it does appear that the denso compressor does use this PAG46 oil.

I did flush the entire system, condensor, evap core, new drier. So it had zero oil to start. Last time I added 2 ozs since the compressor came with 7 ounces. This time I drained some oil out of the compressor, turn it over...but didnt / realize that I shouldve spun the clutch to get the rest out. The oil was clear/no dye. I then added a total of 7-8oz to the system. Would mixing different weights of oil really cause problems?

Not on the first and second compressor change where you had problems.