Hunter 376 - Algae in tank

[EdwardinSTX]

My fuel tank has a serous algae problem. Just a few engine hours after replacement, the fuel filters were clogged, causing the engine to die just 10 minutes from the dock.

What are the options?

How do you get to the tank? I'd like to pump out all the fuel, but how about the residues on the tank walls?

Putting biocide into my full tank would seem to just kill the algae and leave a sludge. Of course, it should have been added before the algae had a chance to grow.

 

[Steve Dion]

Edward:

If you can remove the tank, that is what I would recommend. You can then have it steam cleaned and pressure tested. If it checks out, just reinstall and and re-fill.

If you cannot r/r the tank, you may try to find an alternative method for cleaning it in place.

 

[Don12364]

Been There - Twice!

My H376 suffered the diesel bug.
First remove (unscrew) the fuel pickup dip tube on the top of the tank and clean the fine gauze filter on the end. Yours may already have been removed.
I would now recommend not removing this filter from the dip tube end - unlike what I did.

Remove the fuel gauge sender which leaves a 2" hole in the tank top.
Pump or siphon all the fuel out into suitable containers.
To do this I used a 3' length of 1/4" bore copper tube on the end of a length of clear flexible polythene tube. A pump in the chuck of an electric drill did all the work.
Poking it into the deepest part of the tank first - the inboard side - pump the first of the fuel into a bucket. I bet you will see at least half a gallon of water.
If you do this is unlikely to be condensation but you will have bought it in place of fuel - and paid the same price!
Think where you last filled up and whether his tanks were floating in water or if they had just been refilled. This stirs up the water so you get some. In my case it takes exactly 3 days for the bug to grow to the extent it stops the engine.

Then I took a small 12v bulb and soldered a pair of wires to the contacts, connected it to a battery and lowered this into the tank for a look around.
This enabled me to suck up the last dregs of fuel.
Fortunately there was little or none adhering to the tank walls.

Now check out the fuel line. On my second instance - after I had removed the gauze from the pickup tube - I discovered the entire fuel line was clogged. I had to take out of the boat and take it home and blow it through with an air line (you could do this at a filling station). Fortunately removal was only a matter of threading it through.
Next I discovered the Racor filter body itself was clogged and this too needed removing blowing or poking clear.
Now put it all back together, much of the fuel will be usable if you let it stand and decant it off like fine wine.
THEN ADD A LIBERAL DOSE OF FUEL SET AND swear an oath never to buy fuel again without dosing it with this stuff. Its made in NZ to a 'secret' formula!
It not only kills the bug but it dissolves the microbes so small that they go through the filters and are burned in the engine.
It also absorbs water - but not a half gallon of course.
Do I seem passionate - you bet.

This problem usually strikes at the worst possible moment.
But I have been clear this last ten years or so.

Good luck and have a nice Christmas - if a slightly smelly one.
Let us know how you get on.

BTW: Looking in the tank is really the only way to be sure it is clean. Fuel polishing might get most of it out but you are already in a too advanced state for this - unless the polisher does just as I did.

 

[timvg]

There are mobile services available that can do this. While not inexpensive, I was very happy with the results and felt it was better to "not" practice on my boat. We didn't have the engine quit, but we decided that it was time to clean everything. I couldn't believe the "red" pudding like stuff that they got out of the tank.