new bathroom faucet stems

So, I put in new stems with new washers to get rid of harder-and-harder to shut off bathroom faucets. I put in new stems because the old ones were 15-20 yrs old and cruddy. So, everything's nice and shiny-brassy new BUT (there has to be a but or why else would I be writing?) now when I turn on the water, it comes out a nice steady stream and then slowly drops off to nothing. I turn it up some more and a stream of water comes out and then it slowly starts shutting off. I feel like the stem must be slipping back CCW to shut off but I can see that the faucet is not turning. So, it guess it's the pressure equalizing but I can't figure how it's happening and why and how to fix it!! And it happens equally to both the hot and the cold.
Any hints????
Howard in Santa Rosa, CA Home of "Arnold 'Girlie-Man' Schwarzenegger"
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Howard Moss wrote:

Usually only a problem with the Hot side due to expansion of the washer. Try a couple of washers of different material/make. And don't overtighten the bibb screw, that will distort the washer.
Jim
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Yeah, I was wondering about the washers. I mean, I can't imagine what else could shut off the flow. The other thing is that this is a pressure shift and why would it happen now with the new stems? I put in new valve seats so I may check to make sure they're tightly seated. How important is teflon tape on the water-in and water-out connections to the faucet body? I put some on the Cold side but forgot to do it on the Hot side...
Thanks,
Howard

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Howard Moss wrote:

If the connections aren't leaking, you're good... Jim

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