Sealing Leaking Fuel Tanks: An Alternative to Tank Replacement.
By Wes Cade; Service Manager, Felix Marine Industries.

 

You’ve noticed fuel in your bilge. You’ve checked the obvious. It’s not the racor drain. It’s not the fuel line fittings on the engines or tanks. The hoses seem tight. You’ve come to the harsh realization that your tank is leaking, and that thought is taking the spring out of your step on this fine day. The idea of replacing the tank makes you sick.  The destruction of your boat, the enormous expense, and the loss of good boating days during the refitting process are overwhelming. Especially, after you just spent a ton of dough on reworking the interior, and the beautiful weather in the Northwest is cranking up.

Take a breath and consider an alternative that has been working well at Felix Marine. By draining the tank, cutting access holes in the tank, and using an epoxy sealer, you can avoid tank replacement and the associated huge expense and inconvenience.

Tanks start leaking for numerous reasons. The most common type that we see is due to the corrosive effect of microbial growth (algae) sitting on the bottom of the tank for some time (picture #1).  This corrosive growth traps water in pockets and reacts with the sulfur in the fuel to eat through metal tanks (picture #2).

Our approach at Felix Marine is to clean up the bottom of the tank. We use a wire wheel cup brush to dress up the bottom surface, and coat the bottom leaking area with a thick epoxy sealer (pictures #3 & #4). The expoxy sets up in a few hours. Our experience has been that the tanks generally leak from the low spot in the after section, since that’s where the corrosive solution settles. Cutting one large access hole is usually sufficient to locate the leaking area. We cut a rectangular hole about 20 in X 22 in (picture #5). We then fabricate a cover plate to cover that hole. In the center of that cover plate we put in a removable 6 in access plate (picture #6). This allows a reach through for thru bolting the rectangular plate. Gaskets are used on both sides.

This system works well, and can generally be done in one to two days depending on the access. We also polish your fuel out of the tank into clean tanks while the work is being done. Then we polish it again going back into the repaired tank. The cost is normally around $1500-1800. Compare that to the cost of tearing your boat up, removing and replacing the tanks, and then rebuilding your boat. The Felix Marine tank sealing is considerably cheaper in most situations, and tank sealing gets you back on the water in a relatively short time.

Please call us for further information and free estimates. (206) 286-6500

Felix Marine Industries is a full service boat repair and detail company located on South Lake Union.