Air conditioning compressor "o" ring problem.
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MBWorld Fanatic!
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From: Southeast
2008 C300 Sport, RWD, US
Air conditioning compressor "o" ring problem.
My A/C has gradually not cooled down the car as fast as before so I took the recently out of warranty C300 to the dealer for repair. As they replaced an "o" ring last August, I thought it might be related or that they had missed it and could get it repaired without costing me.
They say that its an "o" ring on the compressor and that it wasn't the same one that was repaired last year.
Originally they told me that the repair would be $534.74. After I complained a little, they told me that they'd split it with me and it would cost half that which is $267.37. To me, that's still outrageous. The "O" ring was backordered to Germany and it may take a couple of weeks to arrive. They did add freon to the system so for now, its cooling fine.
Has anyone else had this problem and if so, what was the resolution????
Has there been any special notices allowing out of warranty C300 2008 to have this repaired at MB's expense????
They say that its an "o" ring on the compressor and that it wasn't the same one that was repaired last year.
Originally they told me that the repair would be $534.74. After I complained a little, they told me that they'd split it with me and it would cost half that which is $267.37. To me, that's still outrageous. The "O" ring was backordered to Germany and it may take a couple of weeks to arrive. They did add freon to the system so for now, its cooling fine.
Has anyone else had this problem and if so, what was the resolution????
Has there been any special notices allowing out of warranty C300 2008 to have this repaired at MB's expense????
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C350 Elegance
If your car is out of warranty, the o-ring failure is probably due to the system not being used during long periods of time in the cold periods. An almost universal warning on A/C is the fact that seals would deteriorate when the system is not turned on at least 10 minutes every 2 weeks. In these systems the fact that they had to add freon means there was a loss. What I would do to open the umbrella before it rains again is to change all seals, instead of only the failed one, and any joint or hose which looks suspicious. Afterwards, there would be no reason for future failure by developing a leak as long as you keep the system lubed by running it as I mentioned before.
I don't seem you are going to be happy this time. Sorry.
I don't seem you are going to be happy this time. Sorry.
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From: Philippines/California, USA
W204 C280
The cost of the O-ring is pretty much nothing. What you're paying for is the labor. If the W204 is anything like previous Benz models, the whole dashboard needs to come out in order to access your AC unit. That's where the expensive labor comes in.
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From: Southeast
2008 C300 Sport, RWD, US
joe,
nyca is right in that when you run the window defoggers, the compressor gets used. Also, I think I recall something about the compressor is constantly spinning and in its design, they're some kind of vains that change position when its called upon.
albert,
Are you saying that the compressor is somehow under the dash? So what's that compressor looking thing with the freon lines between the engine block and the radiator?
nyca is right in that when you run the window defoggers, the compressor gets used. Also, I think I recall something about the compressor is constantly spinning and in its design, they're some kind of vains that change position when its called upon.
albert,
Are you saying that the compressor is somehow under the dash? So what's that compressor looking thing with the freon lines between the engine block and the radiator?
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From: SEATTLE WASHINGTON USA
'08 C300 Lux Barolo Red Beige Leather P2 MM 18" wheels '84 944
Confusion
joe,
nyca is right in that when you run the window defoggers, the compressor gets used. Also, I think I recall something about the compressor is constantly spinning and in its design, they're some kind of vains that change position when its called upon.
albert,
Are you saying that the compressor is somehow under the dash? So what's that compressor looking thing with the freon lines between the engine block and the radiator?
nyca is right in that when you run the window defoggers, the compressor gets used. Also, I think I recall something about the compressor is constantly spinning and in its design, they're some kind of vains that change position when its called upon.
albert,
Are you saying that the compressor is somehow under the dash? So what's that compressor looking thing with the freon lines between the engine block and the radiator?
The condensor is in front of the radiator. The evaporator is in the cabin behind the dash. The compressor, driven by the multi-rib belt is at the lower left of the engine. The clutchless compressor turns all the time and the R-134 refrigerant flow is regulated by a "computer" which varies the angle of the swashplates inside. MB has used swashplate compressors for at least ten years which eliminated the compressor clutch which was another failure item. Therefore, you cannot feel the compressor "kick in" because it a slow process.
Anything else?
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2015 Iridium Silver Luxury Edition C300 4Matic
I've noticed it's also a slow process when I turn it off, where it can sometimes still cool for almost five minutes.
So much confusion....
The condensor is in front of the radiator. The evaporator is in the cabin behind the dash. The compressor, driven by the multi-rib belt is at the lower left of the engine. The clutchless compressor turns all the time and the R-134 refrigerant flow is regulated by a "computer" which varies the angle of the swashplates inside. MB has used swashplate compressors for at least ten years which eliminated the compressor clutch which was another failure item. Therefore, you cannot feel the compressor "kick in" because it a slow process.
Anything else?
The condensor is in front of the radiator. The evaporator is in the cabin behind the dash. The compressor, driven by the multi-rib belt is at the lower left of the engine. The clutchless compressor turns all the time and the R-134 refrigerant flow is regulated by a "computer" which varies the angle of the swashplates inside. MB has used swashplate compressors for at least ten years which eliminated the compressor clutch which was another failure item. Therefore, you cannot feel the compressor "kick in" because it a slow process.
Anything else?
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223.168 & 213.012 & 906.633 & 214.005
The compressor starts and stop slowly when compared to a clutch but is still fast compared to the time it takes for the pressure being released at the evaporator.
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MBWorld Fanatic!
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'08 C300 Lux Barolo Red Beige Leather P2 MM 18" wheels '84 944
Slooowly
But this is a different slow process. The fact that you get cold for some time after the AC has been turned off is from the freon pressure already built up, once the pressure is getting released at the evaporator, you still get some cold even if the compressor is not running any more.
The compressor starts and stop slowly when compared to a clutch but is still fast compared to the time it takes for the pressure being released at the evaporator.
The compressor starts and stop slowly when compared to a clutch but is still fast compared to the time it takes for the pressure being released at the evaporator.
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Perhaps these new clutchless compressors are different, but on the "old" systems it was always a good idea to disengage your AC (not the fan) about a minute before you knew you were arriving at your destination and shutting the car down. I still do it even in this car as a habit.
MBWorld Fanatic!
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223.168 & 213.012 & 906.633 & 214.005
Perhaps these new clutchless compressors are different, but on the "old" systems it was always a good idea to disengage your AC (not the fan) about a minute before you knew you were arriving at your destination and shutting the car down. I still do it even in this car as a habit.
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223.168 & 213.012 & 906.633 & 214.005
But I was after the on/off switching time of the AC compressor itself. I was not able to find real figures for this but it really does not take minutes to turn the swash-plate from one end to the other, preferably a few seconds.
I could try this with Xentry diagnosis, it allows direct control of the compressor cooling power and reports the actual values for refrigerant pressure and evaporator temperature readings.
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'08 C300 Lux Barolo Red Beige Leather P2 MM 18" wheels '84 944
Freon, not.
But this is a different slow process. The fact that you get cold for some time after the AC has been turned off is from the freon pressure already built up, once the pressure is getting released at the evaporator, you still get some cold even if the compressor is not running any more.
MBWorld Fanatic!
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223.168 & 213.012 & 906.633 & 214.005
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C350 Elegance
Another point regarding O-rings is that these are not supposed to be neoprene or buna-n standard O-rings, but O-rings to keep the freon seals tight. These O-rings are not found everywhere and the fact that they bring them from Europe is a cost adding feature that happens not to research a US source for replacements which can be poor performing.
