Thanks. This is definitely electrical. The sending unit is a good thought. Doesn't cough or sputter. Just stops running... dead. Wait a couple minutes. Turn the key on listen for the relay to reset and then turn to start. Bingo, starts right up. I purposely let the tank run below 1/2. Then... still had 6.9 gals out of 20 last time. Filters etc. seem to be running clean.