Hard to find fuel leak in I/O

[gregpatent]

I have a 1985 Glastron I/O with a 30 gallon aluminum gas tank. I filled the tank for winter storage, and sometimes when I pull the boat on the trailer, I find traces (about 1/4 cup) of fuel in the bilge. The filler hose, vent hose, and supply hose are either new or look okay. I also do not feel any wetness on the connections to the tank, the water separator, the transom vent, or low points in the hoses. Is there a way I can safely find the leak without removing the tank and visually inspecting its entire surface, which requires me to remove a portion of the deck, not to mention 30 gallons of fuel? The boat is primarily used in salt or brackish water, and I am not sure how aluminum tanks do over time in such environments. However, if I had a leak in the tank, it would seem that it would be in the bottom where it contacts bilge water and that I would have more fuel in the bilge than 1/4 cup. Any suggestions?

 

[Alpheus]

Re: Hard to find fuel leak in I/O

The filler hose, vent hose, and supply hose are either new or look okay.

Looks can be deceiving. Physically take them off and check them out.

Are you looking for leaks while the engine is running or just looking for seapage after engine shut down?

I would start by putting a fuel pressure test set and see if the leak is on the pressure side or not. It may or may not find it but its a start. You could also completly dry out your bilge and run it on the muffs and look for the "wet spot". Also check the bottom of your fuel pump. You may have a torn diaphram, assuming you have a mechanical fuel pump. Please list more info about your engine/outdrive...

 

[Anchor Management 1]

Re: Hard to find fuel leak in I/O

I work on saltwater boats everyday, and have had to change many many tanks.Most of the time the leak is where there is a rubber strap or foam when the tank was put in.

 

[Bondo]

Re: Hard to find fuel leak in I/O

I work on saltwater boats everyday, and have had to change many many tanks.Most of the time the leak is where there is a rubber strap or foam when the tank was put in.

Ayuh,... Freshwater will do the same thing, in the same places...

 

[180shabah]

Re: Hard to find fuel leak in I/O

Unfortunately, there is no easy way to check, but you need to find it before it goes boom.

 

[havasuboatman]

Re: Hard to find fuel leak in I/O

Just so you know, 1/4 cup of fuel in the bilge is NOTconsidered traces of fuel. The explosive possiblilty of that much fuel in a closed area of an engine compartment could kill everyone in your boat.
I strongly suggest you find your fuel problem.