Andy:
Using chocolate as a fireguard may not be as useless as you suggest. A favorite campfire treat over here in the US is "s'mores", made by melting chocolate and marshmallows, in a sandwich of graham crackers. Check the link below for a brief history of S'Mores, along with a recipe.
Turning to the watch, this is a fairly common problem -- having the watch run perfectly (to tell you the time-of-day), until you start the stopwatch, at which time the whole machine comes to a halt. Over the years, I have had this happen on six or eight chronographs (Heuers and non-Heuers); in most cases it required only an "adjustment" by the watchmaker, and no parts; perhaps once or twice, some minor parts were required. In each case, a good watchmaker was able to get it running properly, with the price of the service in the $30 to $100 range (depending what else required attention).
Parts should be readily available for almost any 1960's vintage Heuer-Leonidas, and once serviced these are real workhorses . . . very reliable.
Good luck with the watch and do give the s'mores a try.
Thanks for the question.
Jeff
++++++++++++++++++++++++++++++++++++++++++++++++++
: Can anyone out there help, please. I have a
: 1960s Heuer Leonidis (sorry about spelling)
: with a stop watch and three dials. I think
: the mechanism is a Valjoux like early Omegas
: of this type. Anyway, as long as you don't
: use the stop watch the thing keeps time, is
: reliable, looks great etc. The trouble
: starts when you do use the oblong buttons
: for the stop watch. The big secondhand
: occasionally stops, which also makes the
: entire watch stop as well. At which point
: the whole thing becomes as useful as a
: chocolate fire guard. I have sent the thing
: to two separate watch repairers, who have
: each (twice) expensively failed to mend it
: and I'm now having a sense of humour
: failure. Is this a common fault? Am I being
: stupendously optimistic in expecting all the
: functions to work? And does anyone know of a
: good, reasonably-priced watch repairer in
: the South East of England who has the skill
: and knowledge to make this problem go away?
: Thank you fo your time. AE