Ray, you don't tell us what size
boat you'll be delivering - and bigger might help over smaller - but Gord's point is worth reflecting on: where are you going to site the generator while underway (and I might add, the quantity of gasoline you'll be needing) so it is chocked in place, emissions won't be a problem for the crew,
noise not bothersome, and where it will be protected from
salt water? If you actually mean 'delivery' (vs. just relocating the boat on some kind of loose sked), you'll need the amps from the generator more at sea (a/p, lights, etc.) than in port, just as Gord suggests. How practical is that for your boat?
This aside, take a good luck at the battery charger on the boat to be delivered and talk with the manufacturer about the compatibility of it with simple gas generators. Often, more sophisticated battery chargers won't
work with simple generators; one reason (but not the only one) is that the charger will want to start out at the bulk
charging rate even if the battery bank is at a 90% state of charge, and this will be more than the generator can provide. Sometimes a simple, secondary battery charger is purchased and clamped onto the battery terminals to overcome these problems...but that can introduce other problems. (There's a reason why
panels and
wind gens are popular...<g>)
BTW a common practice for GAS generator-equipped boats in the islands is to place a measured amount of gas in the tank (not much; note Gord's
consumption figures...) for the length of charge the battery bank needs, start up the genny and then hop in the dink and leave to go swimming, spear
fishing, etc. The genny does it's
work, shuts itself down via
fuel starvation, and the crew returns later to a peaceful boat with charged
batteries. Not a bad way to go...unless you're anchored next to neighbors.
Jack