ignition mystery

[rbolduc]

I have just bought a new boat with an early model Atomic 4 with a Prestolite distributor from a very nice guy who "upgraded" to electronic ignition just
before selling.
He installed a Coil No. - IGEM_05_31 and an
electronic ignition IGEM_12_37 from Moyer's marine
New plugs,new wires,new distribution cap
The electric fuel pump and the electronic ignition unit is plugged directly on the coil's terminals.
After running ok for a while (around an hour, sometimes less) the timing begins to be off and then the motor stops. After a while (from 10 minutes to half an hour) it can start again.
We changed the IGEM0531 coil for another one made for
electronic ignition but the same problem remains.
Does anyone know what is happening?

[Don Moyer]

Your symptoms appear to be more consistent with a fuel-related problem than ignition. The next time the engine shuts down, and during the time that it will not start, please run through the attached troubleshooting guide. You can skip down to the fuel and ignition sections of the guide, since I don't believe you'd be losing compression after the engine runs so well at the beginning of each trip.

Don

[rbolduc]

...and blueish exhaust smoke

I've just remember: a sign that it's going
to choke soon is blueish smoke.
Is that pointing to the same cause?