safe to use above deck fuel tanks?

[C Perini]

Ive got a 1986 20' privateer fiberglass fishing boat. The built in aluminum tank looks to be in rough shape and full of unknown gunk. Do you think its safe to use two 13 gal. above deck tempo tanks instead? Should I strap them down or would it be safer to build boxes over them with holes for ventillation, my thinking is the boxes would keep the tanks secure, out of the blaring sun and out of view. Thanks. CB

 

[rickdb1boat]

Re: safe to use above deck fuel tanks?

CBP <br /><br />No problem either way you want to do it. Just make sure you leave plenty of ventilation if you go the box route, and of course, easy access to the tanks.

 

[18rabbit]

Re: safe to use above deck fuel tanks?

Aluminum tanks are susceptible to corrosion that synthetic tanks are not. It is possible a 1986 boat has fuel tanks that are no longer usable, but they might be ok, too. The gunk is probably from gasoline left sitting for month/years. Gasoline has a really short shelf life before it begins to break down, tho I use it well beyond that. If fuel was left sitting in the tank for a long period of time, there will likely there may be a shellac build up on the inside tank walls. This must be removed completely before the tank can ever be used for fuel again.<br /><br />Tanks and fuel placed lower on a boat appeal to me. Based on what you described, I would arrange for a marine fuel tank maintenance company to come out and inspect/clean the original tank, then go from there. Your fuel tank is not necessarily bad. Corrosion, if any, will likely come from exterior influences, not the fuel. Fwiw, I am still using an aluminum fuel tank that is older than your boat and in great shape.

 

[C Perini]

Re: safe to use above deck fuel tanks?

Thanks guys, my biggest problem is that there is only limited access to the tank via two small deck plates and I can't see much more than the area around the sending unit and the elbow fuel line fitting at the other end which look a little corroded. Getting the tank out would mean cutting out the deck. I don't know what can be done to clean or check the tank as it sits now. oh well

 

[C Perini]

Re: safe to use above deck fuel tanks?

dont you think above deck poly. tanks are the safest way to go in this situation. I wish these damn boatbuilders would start using fiberglass or poly built in tanks because these metal tanks are ticking time-bombs, especially when you cant get at them!!!!!!!

 

[rickdb1boat]

Re: safe to use above deck fuel tanks?

I'd still go with the poly tanks on the deck. At least you know what you've got. If room is no problem, then neither is putting the tanks there..

 

[Boatist]

Re: safe to use above deck fuel tanks?

CBP<br />My 1980 also has aluminum tank but mine is fine. Each type tank has advantages. My tank has screws in the deck and very easy to take off if I needed to replace tank. Should be requirement. I do not know if you do any boating in the ocean but if you do your boat will be more stable and roll less with the tank low in the center. The higher the weight the more it will roll and the longer it will take to recover. Also since gas fumes sink better to be lower than engine ingition sourses. Poly tanks do not corode but they will melt in a fire. Any enclosed tank must be ventelated to be legal. Even if you replace the tank you will need to remove the fuel so why not start by removing the fuel and then getting inspected.<br />Good Luck

 

[AW]

Re: safe to use above deck fuel tanks?

Last summer I replaced an underdeck aluminum tank in a friends boat. It was a pretty big job, took several days. The places where electrolosis had made holes were were visible from the outside of the tank. The tank leaked badly enough that the whole boat smelled like gas. If it's just gunk it might be worth cleaning it out. If it leaks the above deck tank would sure be easier, but you still need to get the gunk out. You might be able to siphon it out thru the filler neck.