Higher capacity topside tanks instead of 6gal portables?

[undone]

I thought the same thing, how and long does someone want to hold onto a tiller handle.

 

[KC8QVO]

Last trip I took I went through 11 gallons (half of my fuel) and wasn't at the half way mark of my planned trip so I had to turn around. I had a 2.5 gallon spare can, but I didn't calculate that in to my fuel consumption because it was intended to get me home if I miscalculated. That day was an 8 hour day, but it included 2 trips through a portage crossing (around 45 minutes to get through each way) and stops for swapping/filling tanks. Yes, lots of tiller holding, but its the only boat I have I can "explore" in. I bought a regular boat seat a few weeks ago after some exploring treks I made earlier this season. I needed a padded seat and back support. So I got that covered. I thought about doing a console conversion, but I think that is a bit far out of the question. Until I can afford another boat I'm making do with what I have.

Based on that last trip I need another 10 gallons to make the trek comfortably on the main motor. My running fuel was 22 gallons, that I planned to burn, then 2.5 gallons on top of that. So add in another 10 gallons and that is 32, but at that rate I'd like to throw in a 5 gallon can as a spare in place of the 2.5 for a total of 37 gallons. With 3x 12 gallon tanks that pretty much hits the mark at 36. I still need to check the burn rate of the spare motor, that could be another big factor.

 

[steelespike]

A very general rule of thumb at wot(wide open throttle) A motor will use fuel at a rate of 10% of the hp. 25 hp = 2.5 gph (gallons per hour).
The 9.9 about 1 gph. The 4 hp .4 gph.It is the same whether pushing a house boat or a runabout.
Actual mpg is determined by the speed achieved.
Needless to say you need to be sure the motors are in tip top shape.If you don't know the condition of the fuel pumps you may want to do a rebuild.
If there is a bad diaphram it could leak fuel into the crankcase wasting fuel.
Its not out of the question that if the 9.9 can't plane the boat and the 25 can the 25 mpg may be competitive with the 9.9.
If you run a lot at displacement speeds,about 6 mph, the 4 may do amazingly well.

 

[Chris1956]

11 gal should give you nearly 10 hours of running time at mid throttle. Was your trip that long? If not, you need to check the fuel pump to make sure it is not pushing unburnt fuel out the exhaust.

 

[KC8QVO]

I figure I am getting a little under 6mpg now. My range on a 6 gallon tank is around 35 miles, so that comes out to 5.8333mpg. I didn't think I was too off the mark there. The motor has a new water pump. I will have to see what all the shop did to it, they were closed when I was up there last so we weren't able to check.

Running speed at WOT seems to be around 22-24mph. At 24mph that comes out to a little over 4gal/hr.

Another tidbit is the last trek I was on was around the 140-150 mile range, and that is about 2/3 where I intended to get to (1/3 out and 1/3 back). That leaves my intended track (the one right now anyway) in the low to mid 200 mile range.

 

[MH Hawker]

Run a serch on weatherhead fuel valves

 

[64osby]

I wouldn't consider a 12 gallon tank portable. I wouldn't want to lift it.

 

[roscoe]

Those are top side tanks, not portable.

Top side, not to be enclosed or put below deck. But they need to be secured.

 

[Chris1956]

Gee, My after hearing about the large distances covered, my thoughts are that the OP should get a larger boat.

 

[64osby]

^^^ or at least a faster one.

Looks like you have a 16' 3 bench tiller. How does it plane.

Are you pushing too much water and not riding on top?

What is the max HP rating for the boat?

 

[KC8QVO]

25hp max, 4 bench. Like a modern lund wc but different style rear bench. 16ft. I was looking at the Moeller tanks today. That is exactly what I want. They have much more obust fuel ports - built in gauge also. The tanks have handles on the bottom of the sides too. My plan is to stack the 3 side by side in the middle floor section, plumb them to a 3 way valve, and run a line back from there. I need a quick disconnect at the tank ends also, though. Not sure exactly how I want to do that yet.

 

[KC8QVO]

Looks like you have a 16' 3 bench tiller. How does it plane. Are you pushing too much water and not riding on top?

The boat planes fine now. I had a 13 pitch prop on it up until this summer. In the past couple years I went out fishing with my brother. With 2 people and gear it was bogging down. So I did some research on props and dropped 2 pitches to 11. With pretty much the same load comparing the 2 props when I swapped them I gained about 4mph and the motor was not lugging so much. With my loaded expedition treks the boat still does a good job. It runs better lighter so it goes through more fuel in the beginning (slower speed) but as I burn fuel it lightens up.

 

[Chris1956]

Gee, for a trip that long, I would want an 18 footer with a comfortable seat, a windshield, a steering wheel, a cooler and a women. But that is just me....

 

[KC8QVO]

Gee, for a trip that long, I would want an 18 footer with a comfortable seat, a windshield, a steering wheel, a cooler and a women. But that is just me....

Ha. I got the second and fifth items covered... Got to work on the other 3...

 

[YoungMind]

Just get 2 18Gal topside tanks, strap them down, plug up, and have some fun

 

[KC8QVO]

Just get 2 18Gal topside tanks, strap them down, plug up, and have some fun

If you can find an 18gal tank that I can carry in and out of the boat/truck that is reasonably priced let me know. It seems the permanent top side tanks are more than twice the price of a 12gal "portable", at least the ones I have found.

 

[Chris1956]

You do not want to be carrying an 18 gal tank. It will weigh 150# or so when full. Strap it into the boat and leave it there. Fill it via jerry cans or at a gas dock.