Just found the cause of an intermittent problem I've
been having. Seems over the last couple of weeks I
thought I had been flooding the engine on startup, Well,
I had but not from what I thought. For absolute years
I've never really had any issue getting the engine to
start. but then just as I'm about to start flying again
occasionally it would be impossible to start. turns out
the ignition fuse was acting like a resistor.
Was hard to diagnose as just touching the fuse made
it work so every time I put the multimeter on it it
would show as ok, and volts at the coils was only ever
slightly lower but obvious now at very low amps. and if
by luck when the engine did start it would continue to
run( guess due to extra couple of volts from alternator)
so no inflight failure, but would only have been a
matter of time.
Anyway now when I should be right in my test phase,
I'm back trying to figure out if I need a redundant
power supply for the engine. hard because of the type of
failure and there are so many single point failures
possible its kind of pointless trying to mitigate them
all.
The problem area was the contact surface between fuse
& fuse holder, Not sure if I got a dodgy fuse block
or if its just the environment.
So do I duplicate the engine power bus, switches
& wiring with diodes where the systems join at each
component( lots a work) or just put it down as a totally
random failure & just check & clean fuse panel
connections as part of the annual inspection?
Andrew