I own two hotels so I've got dozens of toilets. Since starting to fit Torbeck valves a few years ago, we've had endless grief with noisey cisterns and valves which won't shut off, wasted water and loads of expensive callouts for plumbers. In my opinion, Torbeck valves are rubbish. I will never have another fitted. They are unreliable. I've just spent four hours trying to sort out a faulty Torbeck and it's now after midnight. Olive oil didn't work. I've got several spare Torbeck valves which I could cannibalise for spare parts but still no good. Then I refitted the original parts and - Presto! It's working again but for how many hours or weeks is anybody's guess.
This is how to fix a misbehaving Torbeck valve:
1) Replace it with a conventional ball valve, and -
2) Nothing else.
Torbeck valves are like Jimmy Savile or the Space Shuttle: They are brilliant right up to the moment they go wrong.
The Infamous Greg, January 2016