Compressor cycling to often
No question just wanted to post about my recent search for the reason my compressor was cycling so much. I was noticing that my drier was spitting a lot. Measuring it, it was about every 2 1/2 minutes. I crawled around under the coach and could not find any leaks. I put a gauge on my auxiliary air fitting and found it would only leak when the engine was running. If I shut the engine down right after a spit the gauge would drop from 135psi down to 110 psi in about 45 minutes.
After searching the forum I found Jerry Davis's post on 10/15 "Compressor Cycle". The problem he described was the same problem I was having. So I disconnected the air supply line to the turbo air control valve and plugged it. I started the engine and after the first spit I started my stop watch. I let the engine run for ten minutes and it never spit so I shut it down.
Okay so I am happy that I found the problem. Now to get a part. As stated in Jerry's post it is an expensive part. $820 from Cummins new. Dorman makes a OEM replacement for $500-550 and a rebuilt can be had for $330 if your core is good and $400 if not.
Two of the part houses I called recommended not to use the Dorman part saying they don't last. The rebuilt unit uses the original printed circuit board assembly. Right or wrong I chose the Cummins part. I really don't want to do this job again in five years. With Power Club discount it cost $738. I can also sell my core to the rebuilder for $70.
Took the coach out this weekend and compressor cycles are more than ten minutes apart. I'm sure there are probably some very small leaks in the rest of the system. Thanks to Jerry for his post and for the PM he answered.
It is now time to tackle the exhaust manifold leak I posted about a short time ago. Hopefully I can post that I was able to get all the bolts out without breaking any.
2006 Alpine 34FDDS