Water in the fuel tank Mercury Opt 150 EFI

[kiowacampers]

We finally made it out to Lake Pueblo Co. for our first trip of the season. We would run it for about 30 minutes and the 4 beep alarm kept going off. We figured you could run for an hour before the fuel filter would fill up with water. This went on for 4 days and after cleaning the fuel filter about 8 times and 2 times at home, it got really old, really fast. Water in the filter...Yikes... We would get anywhere from an inch or 3/4 full of water in a water bottle. The funny thing was on the last cleanout, my husband dropped the gasket into the lake and it sank... OH NO... 4:30 p.m. on July 3rd tied off in a cove way far away from the Marina and no one in sight. Luckily he was able to fish it out with a net and a very long extension pole. PHEW!!!! I swear we got about a gallon of water out and it kept coming. First we thought we got some bad gas but there was just to much. So after getting home we checked the tank and we think that every time it rained it came in around the gas cap or ran down the inside of the boat and got wet on top of the tank and got in thru the sending unit.

We drained about 9 gallons of fuel with a little pump and filtered out the water

Draining Gas From Boat - Copy (800x600).jpg (310.27 KiB) Viewed 5625 times

This shows the hose in the tank

Fuel Tank Top - Copy (800x600).jpg (270.77 KiB) Viewed 5624 times

This is what we got.

Gas Level 1 (800x600).jpg (281.32 KiB) Viewed 5625 times

So we caulked everything and we will test with water tomorrow to see if any water ends up in the tank. We will also tape a big sponge on the top of the tank. I'm hoping this is what was wrong. Anyone ever have this problem?

[lakerunner]

Thats strange. I have the same filler And never had water get in. Is your filler on back or side?

[kiowacampers]

It's on the side, right rear facing forward. The back end is not waterproof either under the storage seats which makes sense now. I use bubble wrap on the floor to keep stuff dry. I have everything caulked on the outside too. It's an aluminum floor.

[lakerunner]

Is it possible water is getting under cover when underway and pooling on tank?

[kiowacampers]

Is it possible water is getting under cover when underway and pooling on tank?

You know, I just don't know. Maybe you can check your tank and see if it has rubber gaskets on the outside and inside of the fill. Ours doesn't. The hole wasn't cut very pretty and I'm thinking that's where the water was coming from. Hopefully it's fixed now since we caulked it inside and out. It's possible that the water pooled since we had it on a slip for 2 years but we have an enclosure to keep the back dry and I always tarp above the tank and it's really high off the water. Also the aluminum siding is corrugated, not smooth so its not flush. That might be the culprit.....

[Jonvee]

There should be a rubber gasket under the fuel cap also. Make sure it has not fallen out.

[kiowacampers]

There should be a rubber gasket under the fuel cap also. Make sure it has not fallen out.

Were missing that too. I think we might have this problem fixed. Thanks

[Darin]

If it was in a slip for two years and the fuel tank wasn't full of gas, there would be condensation in the tank as well.