Another A/C problem! compressor began tp sieze!
Thread Starter
Melting Slicks
Joined: Jan 2003
Posts: 2,877
Likes: 13
From: Doha
St. Jude Donor '08
Another A/C problem! compressor began tp sieze!
That A/C stuff driving me crazy! After all the effort and $$$ I put in it, it only worked good for 1 day, and today I discovered that my brand new compressor starting to sieze! It would drag the belt hard and producing a squeack sound. I switched off the engine and tried to rotate it by hand, it was fairly strong, much stronger than a normal healthy one!
Now did that compressor was damaged long time back when I filled it with R134 and it has R12 oil in it? although I flushed it few times with a new nythetic SAE 100 R134 compatible oil and it did work good for a day or two. Or is that kind of compressors will not work properly with a R134 and its oil grades? Is it due to too much freon inside? too much oil maybe?
My worst case scenario is to replace it with another new one, but my biggest concern is to have the new one flushed and re-filled with SAE100 R134 oil and face the same knightmare again!
Now did that compressor was damaged long time back when I filled it with R134 and it has R12 oil in it? although I flushed it few times with a new nythetic SAE 100 R134 compatible oil and it did work good for a day or two. Or is that kind of compressors will not work properly with a R134 and its oil grades? Is it due to too much freon inside? too much oil maybe?
My worst case scenario is to replace it with another new one, but my biggest concern is to have the new one flushed and re-filled with SAE100 R134 oil and face the same knightmare again!
Race Director
Joined: Sep 2001
Posts: 10,560
Likes: 439
From: Wellington, FL
St. Jude Donor '11 thru '25
You will need to flush the condenser, evaporator, and hoses before you install the next compressor or you'll end up with the same problem. When compressors seize, there is the strong possibility that they will throw of metal fragments that end up in the system. 
Thread Starter
Melting Slicks
Joined: Jan 2003
Posts: 2,877
Likes: 13
From: Doha
St. Jude Donor '08
Thats really unbelievable! I just flushed the whole thing for the 2nd time in a couple of months! now I need to do the same thing again!
I've noticed that when I switch the A/C on it will work ok without slipping for about one minute before slipping again. When I turn the compressor by hand BEFORE starting the engine and turning the A/C on, I feel its normal and not that hard to turn, does that indicates anything??
I've noticed that when I switch the A/C on it will work ok without slipping for about one minute before slipping again. When I turn the compressor by hand BEFORE starting the engine and turning the A/C on, I feel its normal and not that hard to turn, does that indicates anything??
Race Director
Joined: Sep 2001
Posts: 10,560
Likes: 439
From: Wellington, FL
St. Jude Donor '11 thru '25
Be sure your belt is in good condition. If the compressor turns easily by hand, and I'm assuming the clutch is engaged (eng. off ignition and a/c on), perhaps your belt is the problem.
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 28
From: Florida
From your previous posts it seemed that your pressures were a little high.
As a guide, your low side should be close to your evap temperature and the high side should be 2.2 to 2.5 times the ambient temp.
Having both the low and high side higher usually indicates a failing compressor or a stuck expansion valve.
The 134a is not compatable with mineral oil, so you may well have done some previous damage to it.
BTW A6 compressors call for 11oz of PAG 135 oil, which can be hard to find readily, but usually PAG 150 is substituted for waranty purposes. Sounds like you used an ester oil? Anyway, viscosity of 100 is too thin.
At this stage, have them let out a very little refrigerant. Your aluminum suction line up to the compressor should be cold, but the compressor fitting should not be.
Try it, at this stage you have nothing to loose.
As a guide, your low side should be close to your evap temperature and the high side should be 2.2 to 2.5 times the ambient temp.
Having both the low and high side higher usually indicates a failing compressor or a stuck expansion valve.
The 134a is not compatable with mineral oil, so you may well have done some previous damage to it.
BTW A6 compressors call for 11oz of PAG 135 oil, which can be hard to find readily, but usually PAG 150 is substituted for waranty purposes. Sounds like you used an ester oil? Anyway, viscosity of 100 is too thin.
At this stage, have them let out a very little refrigerant. Your aluminum suction line up to the compressor should be cold, but the compressor fitting should not be.
Try it, at this stage you have nothing to loose.
5th Gear
Joined: Mar 2007
Posts: 5
Likes: 0
The AC system might be over charged with refrigerant and that will cause the pressure on the high side to be too high causing the belt to slip. There could also be air in the system and that will cause the pressure to be too high also.
Melting Slicks
Joined: May 2002
Posts: 2,717
Likes: 121
From: Sulphur LA
St. Jude Donor '05-'06,'11,'13-'14,'16,'18,'19,'24, '25
From your previous posts it seemed that your pressures were a little high.
As a guide, your low side should be close to your evap temperature and the high side should be 2.2 to 2.5 times the ambient temp.
Having both the low and high side higher usually indicates a failing compressor or a stuck expansion valve.
The 134a is not compatable with mineral oil, so you may well have done some previous damage to it.
BTW A6 compressors call for 11oz of PAG 135 oil, which can be hard to find readily, but usually PAG 150 is substituted for waranty purposes. Sounds like you used an ester oil? Anyway, viscosity of 100 is too thin.
At this stage, have them let out a very little refrigerant. Your aluminum suction line up to the compressor should be cold, but the compressor fitting should not be.
Try it, at this stage you have nothing to loose.
As a guide, your low side should be close to your evap temperature and the high side should be 2.2 to 2.5 times the ambient temp.
Having both the low and high side higher usually indicates a failing compressor or a stuck expansion valve.
The 134a is not compatable with mineral oil, so you may well have done some previous damage to it.
BTW A6 compressors call for 11oz of PAG 135 oil, which can be hard to find readily, but usually PAG 150 is substituted for waranty purposes. Sounds like you used an ester oil? Anyway, viscosity of 100 is too thin.
At this stage, have them let out a very little refrigerant. Your aluminum suction line up to the compressor should be cold, but the compressor fitting should not be.
Try it, at this stage you have nothing to loose.
noonie is right on with his suggestions. Do as he says
Neal
Thread Starter
Melting Slicks
Joined: Jan 2003
Posts: 2,877
Likes: 13
From: Doha
St. Jude Donor '08
OK, I am ready to be flamed! It turned out to be the belt needs a little more tensioning! it was dark when I checked it yesterday and I didnt notice that .. I know I shouldnt freak out like that, but I've put A LOT of work in that thing and I was working alone with no garage, under a 100F plus environment, so no way I will do that again!
So things are going fine now, I had it for a drive for almost an hour with no problems, A/C blowing cold, engine temp. is very good, reads exactly 200F off the thermostat housing by the IR gun when I came back home, nothing better to ask.
Thanks guys!
So things are going fine now, I had it for a drive for almost an hour with no problems, A/C blowing cold, engine temp. is very good, reads exactly 200F off the thermostat housing by the IR gun when I came back home, nothing better to ask.
Thanks guys!
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