better refueling for gravity fed outboard

[iam2sam]

Hi. I previously had a 16' aluminum transom canoe (Michicraft) with a 3 HP Gamefisher (Tohatsu) OB that I liked very much. I replaced that with a 16' Sea Nymph semi-V and 25 HP OMC. For my solo use the replacement boat has proven far more trouble than it's worth (another story,) so I'm planning to go back to my previous boating mode (I still have 2 of the 3 HP Gamefisher motors.) The only real inconvenience in using the canoe was that the motor is gravity-fed, and has only a 1 quart fuel capacity. I would carry 2 - 3 1 liter cans of 40:1 TruFuel with me for reserve, but twisting around in he canoe and refueling when the water was less than glassy, especially since the GF gas cap has no tether, was an "interesting" exercise. I'd like to have a 2 - 3 gallon reserve tank on board, and fabricate some easier way to refuel. I have seen threads here and elsewhere about adding an actual vacuum fuel pump and external tank to a gravity-fed motor, but I think that is a more ambitious a project than I want to tackle, and I'm not sure that this motor can be fitted with a pump in any event. What I had in mind was to tap the fuel cap for a quick disconnect fuel fitting, and use a small tank equipped with a fuel line, primer bulb, and the matching fitting. When my motor ran low on fuel, I could attach the line, and use the primer bulb (or possibly some other type of maual pump) to refill the top tank, using the primer bulb. Obviously this is not as convenient as a completely uninterrupted fuel supply, but it seems to me to be a heck of lot better (ntm safer) than hand-pouring gasoline from a can while tossing around in the chop. Any thoughts on this idea? Are there differences in primer bulbs in regard to how many "cycles" will wear one out? Thanks in advance.

 

[Sea Rider]

Gravity engines with attached internal fuel tank doesn't have a built in carb fuel pump to hook directly an external fuel tank. Or even add a mechanical fuel pump attached to engine, carb, whatever.

Could install a larger fuel tank but will need to seat it over engine with a tank support of somekind to work also by gravity. Try to find a small engine with dual internal/external tanks, say a Tohatsu, Merc, 5 HP.

Happy Boating

 

[JimS123]

Use a small 3 gal plastic tank. Instead of having a normal "plug" on the end of the hose, remove the plug and cap it off with a cork. When refueling, remove the cork and squeeze the primer bulb while holding the hose in the engine fuel tank. Make your own tether for the cap.

 

[roscoe]

TRufuel is not really what you want in a cool running outboard motor.
It is formulated for hot running engine, outboards are not hot running.
And at what?, $40 for a gallon and a half, Thats a waste of $34.



I have a 2 stroke Mercury/Tohatsu 4 hp with a 3 quart tank, runs for 10+ hours at moderate trolling speeds.

I would not suggest getting a smaller motor that does not have reverse gear.
The smaller motors have 360* steering, BUT, start pulling a canoe sideways, even for a second or two, and it will swamp. Experience documented, June, 1979, Nagawicka Lake.

So sell what you have and get a motor with a larger tank, OR solve the issues you are having with the 14'er.

 

[Silvertip]

Install a fuel nipple on the tank and attach a small fuel line to it. Run that line to a one gallon fuel tank with a similar fitting in the bottom. When the motor runs out of fuel, hold the auxiliary tank higher than the engine and let gravity work its magic. Keep in mind the portable tank will need to be vented during the fuel transfer. You wouldn't need to turn around with this plan.