Gas tank locations

[Karl]

With the recent discussions about saddle tanks on the Skagit 20, I was wondering what everyone's thoughts were regarding the ideal location for gas, water, waist tanks. I am drawing up my ideas for my Skagit 25 and I'm torn between saddle tanks and center line hull install
I love to hear everyone's experience!

Thanks, Karl

[Sammamish1]

My vote is move the fuel weight forward to counter balance the engine weight.

Attached pictures show the installation Helmar did on my Bell Boy.

[John Berg]

Low center of gravity

Karl, I would take a scientific approach and being I am not a scientist, heres my 2cts. I would try to limit the side to side rocking. I would think that the more weight under the floor the better. I was actualy thinking of converting the old sattle tanks into balast tanks and filling them up while in rough water just to keep the boat from acting like a big bobber. This experience is from the Skagit 20. This would be a guess. I would build tanks to fit the individual sections under the floor. I have been thinking about this since I bought mine so many years ago. Its being prepared to sell so here are some early pictures. Do you have the same amount of room under your floor? John

[Skagitguy]

I would go with two 25 gal each saddle tanks ( like i had on my Farallon ) as far forward as possible toward the bulkhead. On my 17 Skagit i had 2 12gal tanks at the bulkhead. I like the idea of more weight forward. Chuck

[John Berg]

weight forward

I had a problem with my 20 when I first got it. The waves were man handleing the boat. After i placed 3 60lb bags of concrete in the bow I would just plow through them

[McSkagit Tim Jones]

Saddle Tanks vs Keel Tank

On older hulls, there might not be sufficient room for a down the-center-line keel tank. A Skagit 24, might be an exception, not seeing your engine installation.

Contrary to conventional wisdom, putting the weight over the chines enhances stability more than the weight of the tank and fuel down the center of the keel line. This due to the energy needed to get the weight moving vs the weight over the keel which tends to act like a pendulum.

I'd vote for saddle tanks....

Tim

[BruceDrake]

1961 Skagit 20 and 18 had underseat tanks

The 1961 Skagit 20 (Loken version) had 16.5 gallon tanks under the back of the front/sink/back seats. Green pictures.
The 1961 Skagit 18 (Drake version) had 12 gallon tanks under the back of the front/back seats. Red pictures.
In both boats the tanks were mounted on rather than below the floor. There were two side fills on both the 20 and 18 models.
Perhaps Norwegians need more gas :HandHorn1:than people that are only 1/8 Swedish.

[strobee]

Melanie's 20ft Skagit is a tanker with 4 saddle ,tanks from the factory.

[John Berg]

Water line

Maybe the best strategy is having dead weight all the way around the hull at the waterline. I like the tanker concept.

[Karl]

I think that I am leaning towards along the edges below or at the water line. John, yes my 25 has the same stringer layout as your 24. Lots of room to put tanks, foam and storage. Is that a water tank that I see in yours next to the bulkhead?

[TheBronze]

I'd do what they did when they designed the boat.

While hull design has improved drastically since the early days of runabouts, the guys who designed these boats (Skagits (and bellboys)) were naval architects and probably had weight placement in mind when they desinged the hull and placed the tanks. Monk did the 404, not sure if he had a hand in the Skagits or not.

As for putting the weight in the bow... plowing doesn't seem like the right thing for a runabout to be doing. You are basically taking a planing hull and making it a displacement hull. Not what it was designed for. And, these old gals really weren't designed for rough waters anyway. lakes and a calm day on the sound only.

my .02

[Helmar]

Fuel and Weight distribution on old classics

Fuel and weight distribution keeps coming up for discussion it seems.

In looking at how the boats were designed back in those days, the engines they had to choose from, you can kind of see what they had in mind.

Pretty much, balancing them out.
My 1959 came with a Volvo Penta I/O and you can see it being a Offshore, they mounted the Saddle tanks (40 gallons total) up as close to the bulkhead as they could.
The Express 20's, they mounted them more aft depending on the power they used.

And I agree, if you have to put weight in the bow, it means you or someone did something wrong.
The more you have to Kick or Trim up the motor to keep that bow down, means plain and simple. Too much weight in the stern.
Adding weight up front, well, that just means more weight to push around meaning more fuel needed to push it..

Me, I will put as much weight right at the center of the boats balance point as I can, fuel, batteries, tools...

Look at the degree of the transom on most older boats.
Look at the early engines.
If the boat is balanced out with the motor hung on the back, then no need to trim the crap out of it...

Some folks like to make Rocket Science out of it but its not.

Now you have one more opinion in which you can form your own :BigWink1:

[Karl]

And is exactly what I was looking for!

[Tim_Mattson]

Karl,
The designers use a term called "Center of Balance".
The boat is like a big teater totter,weight placed any distance from the center of balance will make the boat react more and more as it is both raised and moved for and aft.
Having the weight centered will help the hull ride the same as payload changes and as gas tanks are emptied.
Weight added to bows will destroy hulls when trailered or driven in rough water.
On top of the floor ,midship and not over 12-15 gallons will keep you safe,then have a portable you can move around as needed ,then connect to quick-release on a fuel filter assy as needed (and/or winterizing system) .
Fills on both sides of boats gets weird at gas stations when they are busy,I`d keep it on the same side as tow rig whenever possible.
TM

[ChuckB]

The one thing we always seem to forget is that fuel, as far as a stabilizing feature, is a depreciating asset. We use it up, and at the end of the trip you have less of your stabilizer than at the beginning. Static weight needs a lot more consideration. As for saddle tanks over the chines, all the Seafairs that I remember from my youth had them, and they rode great. The 19' Sabrecraft in my pic, i had the two Batt's forward, along the chine at the cabin bulkhead (static weight) and two 10 gal fuel tanks at the stern under the splashwell. Full, with the 200 lb Honda, it had a great ride no matter what state of fuel reserve i had.
ChuckB