This kinda goes along with my previous posts about the air tool issue and water in the compressor but.................

I have a 30 gallon Craftsman compressor. And I have replaced the drain plug once in the past cause it was nearly impossible to open and close to drain. Although I have learned my lesson about draining the water from it, I am running in to the same problem again. When trying to drain the water, the thumb screw will not budge. SO i end up using vice grips to open/close it. For whatever reason, whenever I close it all the way, I turn the compressor on and all the air goes right through the drain plug.

Why is this doing that? It's like its not sealing or closing the drain plug to fill up with air. So again, I have to buy another drain plug. Am I doing something wrong?

Here is a link to the compressor I have. It shows the part number of the drain valve I need to replace it but are these a pretty typical size or do they differ from tank to tank? I see these valves at home depot, but unsure of the fit. the compressor parts list does not display the size, but rather a part number.

Any help?

COMPRESSOR

http://parts.sears.com/partsdirect/part-model/Craftsman-Parts/All-Products-Parts/Model-919165570/0247/0703000

DRAIN PLUG

http://parts.sears.c...=&prst=&shdMod=

Since you would have to remove the plug anyway, pull it out and see how much rust and crap got in it when you drained the tank. May have to go to a friend with a compressor and blow out your plug......

Also, I think those only unscrew maybe half a turn to drain. Any more and you damage the threads. Clean it up, put some thread sealant on and try it.

It's possible you have rust in the tank, and the plug, (or is it a petcock?) gets a particle of rust in the workings so that it cannot seal.