Ain't that the truth Mark. For anyone interested, the outcome to the problem that ruined my birthday cruise here...
http://www.trawlerforum.com/forums/s53/hello-coomera-queensland-36335.html#8
...turned out to be something a couple of nips up with a spanner cured. Trouble is, I couldn't find the said fuel leak, as it was only revealed by pumping the lift pump vigorously for longer than I did. It was where the copper tubing fuel line joins (via a metal locking nut), to the on-engine 2º filters. It took the diesel mechanic, who had dealt with this sort of thing before, about half an hour to fix. The tiny leak allowed air to get in and cause an air-lock when we throttled off for the first anchorage. So, it cost me the four day cruise, and $520 for the tow back..! Because, as the boat has been for sale, we had let our sub to the local Volunteer Marine Rescue folk lapse, otherwise the tow would have been free. There's a lesson there I guess.