King keg taps

I have a king keg and a brewcraft keg both with leaky taps. The king keg doesn't seem to have been as bad as it has been, but I've lost at least 4 pints from the other due to the tap dripping. Does anyone have any advice on how to stop them/what sort of tap would work better?

I also gave a king keg which had a useless tap, the thread was poorly moulded meaning that it could not be tightened properly. I since got hold of a more sturdy replacement and it works a treat. The new tap came from a local HB shop, so I don't have a link. It has a good thread and the fitting on the inside of the keg is solid. I'll see if I can post a photo

Sent from my SM-T585 using Tapatalk

Sent from my SM-T585 using Tapatalk

The thread is fine, it's actually leakage out of the tap, not from the space where it screws on (on both legs)