You’ll be quite ok leaving gate valves a quarter turn off the end stop, in fact it’s generally considered good practice.
For penetrating oil I personally like atf mixed with acetone , although a more commonly available equivalent would be motorcycle chain lube. It’s a sticky lubricant carried in a fast evaporating solvent, and it’s designed to penetrate. The best thing you can do with gate valves is cut them out and replace them with full bore lever action ball valves. Far superior in my opinion. H Sent from my iPhone On Thu, 12 Feb 2026 at 11:37, Ralph Corderoy <[email protected]> wrote: > Hi, > > To create some traffic for our newcomer, I thought I'd ask for > recommendations for a penetrating oil to apply to stuck gate valves; the > typical kind found on 15 mm and 22 mm domestic copper piping. > > I've had WD40 suggested, but it isn't the same thing. > > I've quite a few stuck gate valves. Getting applying torque by hand, > back and forth until it starts moving has freed some. I've returned the > open ones to fully open less a quarter turn to help prevent future > sticking. Presumably that doesn't impact flow, with the gate only > cutting in after more turning? > > The tap on the incoming mains is also stuck. :-) > > -- > Cheers, Ralph. > > -- > Next meeting: Online, Jitsi, Tuesday, 2026-03-03 20:00 > Check to whom you are replying > Meetings, mailing list, IRC, ... https://dorset.lug.org.uk > New thread, don't hijack: mailto:[email protected] > -- Next meeting: Online, Jitsi, Tuesday, 2026-03-03 20:00 Check to whom you are replying Meetings, mailing list, IRC, ... https://dorset.lug.org.uk New thread, don't hijack: mailto:[email protected]
