I left the key turned on. When I discovered it the battery was dead and the meter now has about 100 extra hours of time on it. I did not know the clock ran while the key was on. Anyone else have this issue?
Cut the key off in the future. If you are worried about your last oil change interval, change the oil and start your count over, no intense bookkeeping involved.
Some hour meters run off of the machine battery key on power while others have a single wire that spirals around a coil lead and senses the induction created by the coil firing when the engine is running.
