[Roderick]

Well, thanks for all comments. Had a look today cleaning up the cooler. Various bits of rubbish fell off, but the actual cooler doesn't look too bad.
The whole pipe/valve thing wobbles around (green on pic) and there is a 'wire' loose, not attached to anything (yellow on pic) ?
The wettest part is along the bottom of the 'radiator'/grill, and drips off the red plastic tie. Possibly it could being dripped on above but can't see anything.

As you can tell I'm not very mechanically minded and don't like undoing things if not really knowing what I'm doing and will it fit back again after! If I try taking the whole thing off for examination, how does fuel stop flowing?
More comments welcome! Ray