The handbasin mixer unit of an Ideal standard bathroom suite that is about 35years old is leaking from the swivel joint. There is no grub screw to release the spout to replace the "O" ring which I presume is the problem. Neither can I turn the spout and pull it off. The unit is monoblock with quarter turn on/off action for hot and cold.

maxbailey, October 2011

The problem was solved by replacing the wornout special (original) gasket with three close fitting O-rings suitably greased. I had to experiment with various combinations before I got the leak cured.
A year later the busy mixer is still leak free and I have identical spares ready for the future.

GEE, October 2011