Compressor leaking

[WhoWhatNow]

New member here. Been lurking for a month or two and have learned lot.

I'm having trouble with my Porter Cable compressor. We moved recently and I drained the tank before the move. When I went to set up the compressor in the new place, I found that the drain valve was frozen open and would not close. I took the opportunity to install an elbow, a short piece of pipe and a ball valve to make draining the water easier. Here's the problem: I can't get the elbow to seal. Every time the tank starts to fill, air leaks from the tank/elbow connection. I have tried Teflon tape (wound counter-clockwise) and even pipe thread compound. After that failed, I when to Sears Hardware and got a new drain valve with a tread sealant already on and even that leaks. Any ideas? My fear is that I over tightened the elbow and screwed up the treads in the tank

Thanks!

 

[Skin]

if you got transfer or the threads look stripped buy a pipe tap [1/4"?] and run it through to clean them then try. For future reference you dont need to crank down on pipe threads. They're designed to seal.

 

[WhoWhatNow]

if you got transfer or the threads look stripped buy a pipe tap [1/4"?] and run it through to clean them then try. For future reference you dont need to crank down on pipe threads. They're designed to seal.

Thanks, I'll give the tap a try. The was some rust that came out of the tank when I pulled off the old valve.

How much do you tighten pipe threads? 1/4 turn past hand tight?

 

[Skin]

The rust is probably from the wall, the drain usually stays pretty solid as its one of the thickest parts of the tank.

As far as tightening. There is no fixed spec per say as it depends on the material of the pipe [for example black iron vs brass], the quality of the threads and material, and what you're using to seal. Generally finger tightening then 2-3 turns is what i aim for. With teflon tape getting a good start with just your fingers can be a pain so probably 4-6 or so full turns from the start is a good area to aim for.

Dont rule out the idea of a crappy elbow either. Its pretty much all coming from china these days and can be quite crude.

 

[WhoWhatNow]

Skin,

I feel better about knowing that. I don't think I went that tight. I really don't want to have to buy a new tank. Thanks for the help!

 

[nehog]

If you do try to clean the threads, be careful not to run the tap too deep... They are tapered threads.

 

[cubfarm 1]

Just thought I would add, brass fittings are much better about being round before threads are cut on them and the brass is easier to get to seal.

 

[isaac338]

Are you testing for a leak with soapy water? Are you positive it's leaking at the joint you think it is?

Not to sound like an ***, but if you're checking just by feeling for leaking air with a finger, that's a notoriously unreliable method... (ask me how I know!)