Water in diesel.

Launched my Merry Fisher 655 on 29th March after winter lay up.

The boat is fitted with a Volvo Penta D3 110.

The fuel tank was topped to the brim over the winter months when the boat was ashore.

I moor the boat at Yachthaven in Plymouth.

My first trip this year was last Friday when I steamed down to the Brendons and then on to Hatt Rock near Fowey ( had a few reasonable pollack and one small cod which I put back ).

To the point. About 2 miles off Rame Head the digital alarm sounded with the message " Water in fuel ".

I limped back to Plymouth, and switched off to fill up the tank again at Yachthaven.

Started the engine again , and the message had disappeared and all seemed normal.

I drained the pre-fuel filter bowl twice and have fitted a new pre-fuel filter.

I noted that the filter I took out , even though it had only 6 hours use was black with dirt on the bottom half.

All seems to be running smoothly now.

The boat is 5 years old and I've never had the fuel tank out to give it a good clean as it's a real b***t**d

to remove.

Anyone know of a procedure whereby the tank can be effectively cleaned in position ?

Maybe try and dip that absorbing "sock" into the fuel tank thru the fuel level sender hole (remove sender), and see what it soaks up? WaterWick or similar (http://www.supplylinedirect.com/specialty/waterwick-fuel-tank-water-socks/)

Ayuh,.... Search up "Fuel Polishing".....

Biodiesel cleans the fuel system really well.
If the boat is running well, and is only 5 years old, I wouldn't worry. Keep a spare filter on board and let her rip. It's hard to judge fuel by a dark filter.

Hope you have it resolved by now. If not, as sugested "fuel polishing" is the way to go. Untreated you know that you may experience serious trouble during terrible weather conditions, or dangerous seas together with possible damage to the engine.

Here, all fuel is removed from the boat's tank, multi filtered into storage drums, the tank interior is brushed clean, rinsed and vacuumed dry. The filtered fuel, mnus moisture and dirt is then replaced into the boat's fuel tank.

One caution: Often fuel tanks have one or more interior baffles impairing interior cleaning. One can only do the the best job possible. If alge is found in the tank a second cleaning may be required at a later date.

Just my take on it, hope this helps.