[Maxfly]

Originally Posted by MG ZS STE

have you tried unscrewing the plunger (think they're torx bits) and cleaning it. you get better access to all the seating faces. i squirted a bit of silicon spray down the shaft and worked it in and out a bit as you can move it a bit more when its off.

An emminantely logical suggestion, thanks for that I will give it a shot. Think the silicone is a good idea!