Hot In Charleston
08-09-2010, 09:39 PM
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Hot In Charleston
Hello good people, here I am again asking for help from the Benz lovers. As you know, I have a 1988 300 SE. Recently I have been having a few issues with it. This is the latest one. My Air conditioner. When I get in the car, the ac is cold. If I travel for about 30 mins, it quit cooling. I can pull over the side of the road, cut the engine off and restart. The ac will resume cooling or another 20 to 30 mins. I am lost. I pulled the relay and opened (Klima) nothing seems to be out of the ordinary. Also, sometimes when it rains, the same issue happens. At first I thought that water was getting under the hood of the car. But non-to that effect. Can someone help me…
I have stopped on several occasions to see what is going on under the hood while the engine is running. The clutch was disengaged on the AC unit. I checked the high-pressure switch, the wiring to the switches and the connections to the AC unit it self, I even thought that it may have been the high speed switch. But it happens at all speeds and there seems not to be anything wrong with the connections and all. I have removed the AC relay and replaced it while the car was running, after a few seconds it started. I still don’t think it was the relay, but I do have one on order. I just checked the temp sensor in the car and it seems to be fine as well. I did discover something, I put some gauges on the system and it seems as if the low side is running a higher pressure than it should. I have started to lower the low side to about 30 pounds. The high side is fine at around 245. Tomorrow I will replace the dryer and vacuum the system for a couple of hours, starting over. Still searching and looking for more advice. The next time it shuts down I will disconnect the mono valve and see what happens. If it starts I would assume that I would need to replace the monovalve.
I have stopped on several occasions to see what is going on under the hood while the engine is running. The clutch was disengaged on the AC unit. I checked the high-pressure switch, the wiring to the switches and the connections to the AC unit it self, I even thought that it may have been the high speed switch. But it happens at all speeds and there seems not to be anything wrong with the connections and all. I have removed the AC relay and replaced it while the car was running, after a few seconds it started. I still don’t think it was the relay, but I do have one on order. I just checked the temp sensor in the car and it seems to be fine as well. I did discover something, I put some gauges on the system and it seems as if the low side is running a higher pressure than it should. I have started to lower the low side to about 30 pounds. The high side is fine at around 245. Tomorrow I will replace the dryer and vacuum the system for a couple of hours, starting over. Still searching and looking for more advice. The next time it shuts down I will disconnect the mono valve and see what happens. If it starts I would assume that I would need to replace the monovalve.
