A/C Compressor?

[someday31]

Originally Posted by rkvons

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....

[j cAT]

Originally Posted by someday31

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. .

[someday31]

Originally Posted by j cAT

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?

[j cAT]

Originally Posted by someday31

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.

[Tech II]

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.....

[someday31]

Originally Posted by Tech II

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?

[brcidd]

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.

[MT-2500]

Originally Posted by someday31

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.

[someday31]

Originally Posted by MT-2500

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.

[j cAT]

Originally Posted by someday31

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.

[MT-2500]

Originally Posted by someday31

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.!!!!!!!!!!!
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.

[someday31]

Originally Posted by MT-2500

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....

[someday31]

Originally Posted by MT-2500

To much oil.!!!!!!!!!!!
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.

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?

[j cAT]

Originally Posted by someday31

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.

[MT-2500]

Originally Posted by someday31

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.