Fuel Tank Location

[joliette]

My twin integral tanks are constructed from grp over ply. They are over 40 years old and no longer suitable for use, due to the ethanol that is now going into our petrol. They are located down the port and starboard sides beneath the cockpit floor. It is very difficult to access all areas of the inside of the tanks to prepare them for application of a protective coating and, in any case, it is a risk that such a coating would fail. Removing the tanks or removing the tops to prepare them for liners would require major destruction of the cockpit, which is something I would like to avoid!

I am considering leaving the existing structure in place and inserting two new tanks, between the old tanks, down the centre line of the boat. This would shift the weight of the fuel lower in the boat and about the centre line, which in my mind ought to increase stability(?)

The boat is a 25ft deep V Levi design, similar to a Triana.

Can you see any issues with what I am suggesting or think of any alternatives?

 

[MapisM]

Can you see any issues with what I am suggesting or think of any alternatives?

Nope. Actually, I'm even wondering why it wasn't built like that originally.

 

[AndieMac]

I am considering leaving the existing structure in place and inserting two new tanks, between the old tanks, down the centre line of the boat. This would shift the weight of the fuel lower in the boat and about the centre line, which in my mind ought to increase stability(?)

Can you see any issues with what I am suggesting or think of any alternatives?

I agree with MM, centreline should be fine.
Are the twin tanks for an individual fuel supply for twin engines, or because of space limitations due to the structural arrangement of the boats framing?

 

[joliette]

The twin tanks are to supply twin engines, each engine having a dedicated tank. The idea is to have two completely separate systems so that if one fails the other should keep going! It would also be possible to install one large tank as an alternative. However, the width of this would be greater than two separate tanks and I was thinking that this could increase the sloshing of the fuel, which may effect stability more than containing the fuel in two separate tanks?

 

[neale]

I was thinking that this could increase the sloshing of the fuel, which may effect stability more than containing the fuel in two separate tanks?

That shouldn't be a problem with a suitably baffled tank.