CONTINUOUSWAVE

I have a 1986 Outrage 18, and after 36 years in saltwater, it looks like it’s time to replace the aluminum fuel tank. As long as I am pulling up the floor, I thought about having a local supplier fabricate a shortened fuel tank to make room for one or two thru hull transducers and a direct overboard drain in the fuel tank sump (as opposed to a drain to the splash well). I plan to install new flared brass tubes and O-rings for the sump drain.

Give me a recommendation for a aluminum fuel tank fabricator located in Southern California.

I have heard of an artisan named Berry in Costa Mesa, California.

Regarding installing a new fuel tank with lower volume capacity: with a modern outboard engine the fuel economy will be about double of an old carburetor two-stroke-power-cycle engine, so having a bit less fuel capacity on board should not be a problem--unless you really need very long range for your boating.

Rather than install a [through-hull] drain tube [in the fuel tank cavity], reinstall the tank with only limited foam in the corners. Install spacers to allow for support and air movement. This method will allow any moisture to evaporate. Spacers can be made of phenolic or plastic material. Removing the [circular deck access] inspection ports will also allow moisture to escape.

Cutting into the hull for drains and transducers should be done with the utmost caution and skill and for very compelling reasons.

A professional fiberglass worker who is knowledgeable with Boston Whaler hull construction should be hired. Not just any Joe from a yard. Installed incorrectly, it can result in thousands of dollars in repairs. Several years ago I provided technical support to a new owner in Australia who bought a pre-owned Whaler with a damaged hull due to an improper after market installed thru-hull transducer. The repairs took a great deal of time and cost a significant amount.

Local fabrication of the fuel tank is a good idea because shipping a large aluminum fuel tank to California from an East Coast fabricator will probably cost more than the tank's cost.

Your idea to create a hole in the hull for the purpose of letting water in the fuel tank cavity drain to the sea seems a bit strange. The water line of an OUTRAGE 18 will be much higher than the bottom of the fuel tank cavity, and putting a drain to the sea in the cavity will probably let more water into the fuel tank cavity than it would ever let out.

Also, what is your plan for plugging and unplugging the drain? Once the fuel tank cavity is covered by the cockpit deck, to get into the bottom of the fuel tank cavity to plug or unplug a drain there would be quite awkward.

Phil and Jim,

Thanks for the great feedback.

Phil T:

Rather than install a [through-hull] drain tube [in the fuel tank cavity], reinstall the tank with only limited foam in the corners. Install spacers to allow for support and air movement. This method will allow any moisture to evaporate. Spacers can be made of phenolic or plastic material. Removing the [circular deck access] inspection ports will also allow moisture to escape.

I've seen the prior posts on that and I agree your suggestion sounds like the best and driest solution. I would like to avoid moisture trapped between the foam and the aluminum tank sides, which seems to be happening now (from what I can see through the Beckson plates).

Now when water gets in the cavity and evaporates, it leaves salt residue on the top of the tank, and probably between the tank and foam. I think the salt might contribute to corrosion. I want to flush salt out of the cavity with fresh water, drain and let dry.

jimh:

Your idea to create a hole in the hull for the purpose of letting water in the fuel tank cavity drain to the sea seems a bit strange. The water line of an OUTRAGE 18 will be much higher than the bottom of the fuel tank cavity, and putting a drain to the sea in the cavity will probably let more water into the fuel tank cavity than it would ever let out.

Also, what is your plan for plugging and unplugging the drain? Once the fuel tank cavity is covered by the cockpit deck, to get into the bottom of the fuel tank cavity to plug or unplug a drain there would be quite awkward.

Currently I have a drain sump in the aft starboard corner of the cockpit, forward of the splash well. At the bottom of this sump is a brass drain tube with a T-handle plug. That one is also below the water line, so I have that plug in when the boat is in the water. When I pull the boat out of the water, I remove the T-handle plug and the boat drains. I do this whenever I pull the boat out of the water and flush the cockpit with fresh water. I would put a similar drain tube and plug in the sump of the fuel cavity, which I could remove when the boat is out of the water and I want to flush and empty the cavity.

I would access the plug through the current Beckson pry-out circular deck access plate where the fuel pickup is located.The current fuel pickups have much smaller mounting flanges than my FMT tank, so the pickup and drain plug could both be accessible through the current Beckson plate, or I could install a larger oval or rectangle pry out deck plate to access both the sump drain and tank pickup fitting if I can't get to both through the current 8-inch round plate.