Originally Posted by Goodnewsboy
As between the two options, a properly managed gasoline inboard engine seems preferable.
Powerboats use gas, cars use gas. Gas isn't the problem, but ignorance can blow you up. Run the blower, make sure the alternator is "marinized" (spark-shielded), double-clamp all hoses, and install a sniffer. Think twice about installing propane, or if it's a small boat, a Coleman stove on a plank in the cockpit plus a rail barbeque running those two-pound bottles seemed to serve us just fine in Toronto where the weather isn't as amenable as Florida.
I have rebuilt and installed an Atomic 4 in my 33 footer and it runs like a charm and is quite economical to boot. I actually REDUCED my gas tankage from 15 to 11 U.S. gallons because I was having trouble using a tank a season. Also, I wanted extra locker space for lines.
Given that I motor off the mooring, get head to wind, and then switch off and get to sailing, that's not surprising. I use about 3/4 gal/hr. at 5.5 knots, which gives me enough range to find a gas station anywhere. If I am motorsailing, I have refuelled enroute from jerrycans, but this is rare.
My new much larger boat has a fat diesel in it and enough tankage for about a thousand NM of range, but it has its own issues, primarily the availability of diesel (and its cleanliness) in certain places, and the fact that diesel engines, unlike gas, really don't enjoy the typical "motor in and out from the basin" scenario. They want to get nice and hot, and so ironically, I am leaving the engine on longer just to warm it up, knowing that the bearings will thank me for not switching it on for just 10 minutes in the cold April air to get beyond the breakwall. So I am burning more diesel than I'd like...because it's a diesel!
This is not a concern with the Atomic 4 anymore than it's a concern with an outboard or a chainsaw. Gas engines can bear short periods of activity. This characterizes a lot of sailboat use...otherwise we'd all have trawlers, right?