You can check out the gasoline-powered single-engine motor boat I added recently:
{
"type": "vehicle",
"id": "boat_motor_single",
"name": "motor boat",
"blueprint": [
[ "|--\\" ],
[ "|==O>" ],
[ "|--/ " ]
],
"parts": [
{ "x": 0, "y": 0, "parts": [ "frame_vertical", "metal_boat_hull" ] },
{ "x": 1, "y": 0, "parts": [ "frame_horizontal", "metal_boat_hull" ] },
{ "x": 2, "y": 0, "parts": [ "frame_horizontal", "metal_boat_hull" ] },
{ "x": 3, "y": 0, "parts": [ "frame_sw", "metal_boat_hull" ] },
{
"x": 0,
"y": 1,
"parts": [ "frame_vertical", "metal_boat_hull", "engine_1cyl_large", "alternator_bicycle", "battery_motorbike" ]
},
{ "x": 1, "y": 1, "parts": [ "frame_cross", "metal_boat_hull", "trunk" ] },
{ "x": 2, "y": 1, "parts": [ "frame_cross", "metal_boat_hull" ] },
{ "x": 2, "y": 1, "part": "tank", "fuel": "gasoline" },
{ "x": 3, "y": 1, "parts": [ "frame_cross", "metal_boat_hull", "seat", "seatbelt", "controls", "dashboard" ] },
{ "x": 4, "y": 1, "parts": [ "frame_horizontal", "metal_boat_hull", "windshield" ] },
{ "x": 0, "y": 2, "parts": [ "frame_vertical", "metal_boat_hull" ] },
{ "x": 1, "y": 2, "parts": [ "frame_horizontal", "metal_boat_hull" ] },
{ "x": 2, "y": 2, "parts": [ "frame_horizontal", "metal_boat_hull" ] },
{ "x": 3, "y": 2, "parts": [ "frame_ne", "metal_boat_hull" ] }
]
}