i was trying to replace a leaking plastic drain valve on my gas water tank but it broke off leaving part of the treaded piece inside. i tried using pliers to unscrew it but it won't budge. any suggestions??

Try an extractor or use a hack saw blade and GENTLY cut the threads not to score the female threads inside the tank ..

thanks. i ended up sawing the piece off. now using a brass valve instead of the cheap plastic crap!

Brass valve is the way to go, to bad the manufacturers are so cheap on quality control