I've noticed however that one of the studs in the inlet is shorter than the others - I think it has come loose, because it can spin around and someone hack sawed (quite recently) the bolt off. Someone sawed the end off the nut/stud anyway!

Is it something replaceable? I trialed screwing a bolt on - it just fits:

I can't tighten it much though, because it spins around - If its ok to leave it in I'd have to secure it somehow? I was thinking of sawing a slot in the end for a screwdriver?
I'd appreciate any input!
Also - is it ok to clean with plain old washing up liquid, any bits I should be careful about? And how on earth do I get the plunger from the dashpot?

