Tom,
I did the same thing with a 1964 VW1500. The alternator would work sometimes, the starter was bad, and the 6 volt battery was marginal. I pushed it to start, hoped the alternator/battery would get me to where I needed to go, and parked on hills.
I really believe the battery would last pretty long with an outboard. I looked at the BF150 specs and it shows the motor uses 11 amps out of the 51 AMP alternator output at 2000 rpm. With a fully charged battery, that would give you a lot of hours if the motor was the only load.
Tom
I did the same thing with a 1964 VW1500. The alternator would work sometimes, the starter was bad, and the 6 volt battery was marginal. I pushed it to start, hoped the alternator/battery would get me to where I needed to go, and parked on hills.
I really believe the battery would last pretty long with an outboard. I looked at the BF150 specs and it shows the motor uses 11 amps out of the 51 AMP alternator output at 2000 rpm. With a fully charged battery, that would give you a lot of hours if the motor was the only load.
Tom