I lost the engine earth on my old 180 while driving... the engine carried on till I turned it off (the dials went crazy then nothing from them though!) after that would not start again...
I'd say check the earths to be sure, make sure the click you are hearing is not just the relay and the spade hasn't fallen off... (been done before!) and double check the battery too.
Another quick fix some times is to whack the starter motor while turning over, sometimes this jumps it into life
