Fuel tank modification

[pascoea]

Hey boaters, I need some advice on if I'm about to do something dumb...

I really (really really really) want to get rid of the portable tank in my boat. It's a 75hp with a 6 gallon portable tank. For fishing it's fine, but if we're going tubing I need to bring a gas can on board and stop half way through the day to fill.

Anyway, I bought a 12-gal Moeller poly tank (link below). The thing ALMOST fits perfectly in the spot I have available (Port side, in the stern) but there is zero clearance between the motor well and the tank, and I'm worried that it will rub through.

What I'd really like to do is hit that corner of the tank with a heat gun until it's pliable and squish it in about a half-inch. 1) How dumb of an idea is that? 2) Any better suggestions? (Besides getting a different tank, that's the only model that is close to fitting.)

Boat is a 1984 16' Blue Fin aluminum.

Thanks guys and gals.
-Adam

 

[JASinIL2006]

I don't really have any better ideas, other than having a custom tank made. I'd be very concerned about heating the plastic and possibly changing the properties of the material. A boat would not be the place to experiment with this sort of thing; if the plastic becomes weak or brittle from heating and leaks, you go boom.

 

[JimS123]

That would destroy the tank. Besides, its a permanent type tank that is intended for permanent installation below deck. Filling it would not be convenient, plus look at the UV rating!!

Look at a portable red 12 gal tank and see if that fits. There was one listed on the bottom of the very page you cited.

If that doesn't fit, buy another 6 gal tank. You can even add a 3-way fuel valve so you don't need to move hoses when switching tanks. On my last OB boat I always carried 3 portable tanks right in front of the transom.

 

[tpenfield]

Trying to modify the plastic tank would go on the list of bad ideas. You could get a custom tank made (out of aluminum)

 

[jetboater]

Agree with the others—-you don’t want to modify that tank.

As others have said, best bet is to find another tank or use several 6 gallon portable tanks and just switch the fuel hose to the next one as one runs dry.

That permanent tank will need to be strapped down and a filler hose and vent line attached to it and the filler hose will need some sort of permanent fuel filler cap mounted somewhere.

A portable tank has all these things built into it.

 

[gm280]

IF your plastic tank is very close to fitting, why don't you grind the boat to allow it to fit? That way you keep the tank configuration (in case you need another as a replacement down the road) and you can redo any boat grinding if need be. The boat can be fitted to the tank... Just an idea.

 

[pascoea]

I appreciate the advice guys!

Upon further research, it appears that XLPE is a thermoset plastic, so heating is not recommended. So that is out.

As far as UV, I don't think this will be an issue, as it be enclosed under the transom.

Part of the reason for wanting to do this is not having to haul portables tanks in and out of the boat. Those damn things get heavy, haha. I like the idea of having an external filler available.

Grinding away at the boat isn't an option, as the tank is sitting basically right against the side of the boat and the motor well (both aluminum)

Again, appreciate the advice. Looks like I'm back to the drawing board.

 

[JimS123]

Part of the reason for wanting to do this is not having to haul portables tanks in and out of the boat. Those damn things get heavy, haha. I like the idea of having an external filler available.

One of the reasons I bought a Boston whaler is because it DID have portable tanks. Hauling the boat to a gas station is too much of a hassle, and the cost of gas at a marina is a non-starter.

 

[pascoea]

Jim;
That's a fair point, and makes a lot of sense! I keep the boat at the house and trailer it to whatever lake I'm headed to, and drive right past a gas station on the way out of my neighborhood.

And because I know you all were waiting with bated breath on this one... I ended up purchasing a different size tank that should fit with no modifications. I'll get a pic up once I get it installed.