Hi,
I seem to have a slow leak at the water shutoff valve under my kitchen sink. The leak is coming from the part that is used to turn is on and off (sorry don’t know the specific name).

The problem is that the pipes running to the shutoff valve are polybutylene. The valve itself is metal as well as the hose running from the shutoff valve to the faucet. I went to Lowe’s and they informed me that they no longer sold valves used for polybutylene pipes.

Can anyone tell me where I could find a 3/8 (polybutylene side) to 1/2 (metal side) straight shutoff / inlet valve?

Thanks a bunch.
Chad

Chad... seems to me that you have a leaking packing nut at the shutoff stem/handle. This is usually veryyyy easy to fix. Just grab onto the valve (hold against yourself) and tighten the packing nut a bit until it reseats the seal around the stem... packing nut is made to be tightened so no sweat really!

Do not overtighten here... start with a 1/4 turn... then another... you should be able to feel it cinch up a bit. Then try that.. could last years after this so do not rush to replace.

Dry area up completely then put tissue paper under stop and see if gets wet over time... bet this does it though.

If it does not then just purchase a new straight valve and replace riser to faucet with a flexible no burst riser... or maybe someone else on line will be familiar with the part you are looking for.

Hey good luck... hope this helped. If it did, please RATE THE ANSWER by clicking on button below. Thank you.

You probably won't need a new valve but just in case you go looking one
You said;

The valve itself is metal as well as the hose running from the shutoff valve to the faucet
Then you said;

3/8 (polybutylene side) to 1/2 (metal side)

I think that's backwards.