Bathroom sink shutoff valve leaks when turning

[Ramias]

No leaks ever from this sink area. Tried to shut the water off to replace a faucet (easy, right?).

Turned the shutoff valve and water started spraying out. So with the valve open all the way -- no spraying. With the valve closed all the way -- spraying. I've had this house 8 years. It's 18 years old. Valve has probably never had a reason to be turned until now (original builder vanity and faucets).

It looks like it is screwed on to the copper inlet pipe and I was able to easily screw on the new sink supply lines. So I don't think it uses compression fittings, but otherwise looks like this:https://www.homedepot.com/p/BrassCr...-Multi-Turn-Straight-Valve-PR14X-C1/202047069

How can I fix the spraying when it is turned on/off? Should I be concerned, or just leave it be?

 

[Terry]

CPVC stop glued on? Sometimes snugging up the bonnet nut below the handle fixes that.
I normally open all the way and then back in a bit.
If closing all the way sprays, you can turn all the water off until the job is done, then reopen.
If it's still leaking, then the job gets bigger and a new stop.

 

[Sponsor]

 

[Terry H]

There is packing around the bonnet nut and tightening up the bonnet nut will usually stop the leaking. It depends if this has been use before etc etc.

You can buy the graphite packing and redo it or replace. I recommend putting a 1/4 turn stop on but it depends what is stubbed out of the wall. If it’s galvanized anywhere in there very often they break and you’re in a bind.
Whatever you choose hold the stop sturdy while working on it to prevent any leaks elsewhere.

 

[Ramias]

It is the same general shape as the valve in that picture but definitely copper pipe.

the job is done. The spraying only happens for the one second it takes to turn from full open (no spray) to full close (also no spray).

I doubt this valve has been turned in 18 years. So my question is how risky is it to leave it open (currently open with no leaks)? I can get a pro here by a Wednesday.

 

[Terry H]

I have never seen the packing blow out and spring a major leak all of sudden. I have seen the washer that turns water off blow out before though.

If it is not leaking right now then you will be fine.