Tub faucet leak- cant remember the rule
 

People,

There is a rule regarding which of the 2 types of leaks one should be aware of- My leak occurs ONLY when faucet is on. It leaks from the cold water knob. When faucet is off, no leak.

I remember ths was key in determining if a leak is caused from the knob washer, or the main faucet stem seat/washer.

Thanks!

I've never heard of a "rule" for figuring it out.
In your case it's the stem seal.
If one's leaking may as well fix both at the same time even if it's not leaking.

Good deal, Joe. Should I start with unscrewing the faucet , then look inside at he innards for some type of washer/o ring?

some have a hex nut under the handle you can try tightening a little or you might have to buy some packing material, others have o-rings around the stem on the inside and you would have to remove the stem to replace it.

Thanks, Danny. Will do it.