<HTML><HEAD><TITLE>HTML Message</TITLE> <META http-equiv=Content-Type content="text/html; charset=windows-1252"> <STYLE></STYLE> </HEAD> <BODY style="BORDER-TOP-STYLE: none; BORDER-RIGHT-STYLE: none; BORDER-LEFT-STYLE: none; BORDER-BOTTOM-STYLE: none"> I try to remember to open the drain cock on my compressor tank every time I've fired it up, and usually do.   But I've noticed that often the hiss of air seems to stop, like something is clogging it, then it suddenly hisses forth loudly again. I don't notice any great rush of water when this occurs and I tilt the horizontal tank back and forth to try and make sure all the water finds the opening.   So I'm wondering if some kind of gunk builds up in their, maybe the way it does in refrigerator drains. Anybody experience this? Should I ream with a pipe cleaner or some such? Alan Barnard Salem, MO Joshua 24:15 </BODY></HTML>