Fiberglass boat modification???

[Iwish]

I posted this in another forum but wanted to get a broader audience so I am posting it here as well. Thanks for any help.



I am considering adding an additional tank to my boat. I have a fish box in the floor and it seems there is plenty of room in front of it and behind it to add a gas tank. I would want it mounted under the floor, obviously, but how do I tell if there's enough room for it and if it would be safe? Is there a place that does this kind of work in the valley, Albany, Salem, Corvallis? The boat is no longer made and hasn't been around for 10+ years so it's likely I won't find out any details about it. Thanks in advance for any advice and/or suggestions.

[Chrome Bumper]

You can get aluminum built custom. Check ebay for salvaged one, you might get lucky and find one that fits your space. Quinn's boat yard in Washington has a pile of them. Coast Gaurd has standards for them. Any you use should have their label. They have seperated outlet, vent line and a fill lines and pressure test to 3 psi I believe.

[Iwish]

Thanks CB.

I have access to a 35 gallon tank that I think will work but may end up going that route, custom or Ebay. What I am really wondering though is how do I find out if it's feasable? Do I just cut a hole and if it fits, great and if not, oh well. Cover it up and move on? How do I find out how much space is under there? Clearance issues, weight, support, etc...

[Chrome Bumper]

Maybe cut a cardboard template of the bottom of the boat, lay it out, find the stringers, bulkhead/framing and cabin sole and lay it out on paper?

Weight and support is a black art. Making it hell for stout works for me. If you are placing it near the center of gravity trim won't be effected much.

The old saw 'measure twice cut once' works for boats too.

Fiberglasssupply.com and the bigbox building supply has all the wood, resin and reinforcements you will need.

[bigredapes]

I don't know exactly where in your boat your fish box is, so where in front/behind you would be adding the tanks, but many people frown on putting fuel tanks in front of the center of gravity or planing surface of a boat, with the reason that in chop it will end up bouncing up and down so much more.
Just something to watch out for.