Polished Tanks

[The crime scene]

I have a boating friend that has taken his boat from Kentucky and now in Florida for the winter season. He has had some engine issues and the mechanic told him he needs his tanks and fuel polished. I have read up a little on it and still researching the topic.

Please enlighten me on what causes this and how to prevent it.

Keith

 

[Phasma]

From what I know its nothing more than filtering any water and contaminants from the fuel. The tank is cleaned of the sediment and crap on the bottom. It is almost impossible to 100% prevent as it has a lot to do with the fuel supplier. As for water in the tank, you can drastically reduce it by keeping the tanks full. It reduces condensation. I have as yet not owned a deisel boat but certainly hope to in the future. Keeping fuel filters clean will also help prevent plugged injectors. Perhaps one of the deisel guys can way in on this

 

[ttmott]

The main issue is algae which forms in that water to fuel layer. His Racor filters are probably plugging up with the algae byproduct and causing the engine issues.
Polishing can be as simple as recirculating the fuel through a filter bank or as complex as removing the fuel and filtering then separately cleaning the tanks. Usually, the fuel needs to be shocked with a biocide like BioBor during the polishing process. I had filled with bad fuel in the Bahamas years ago and ended up with a serious algae issue which required the fuel to be polished. It was a two day process.

 

[Carpediem44DB]

On the 506 I am purchasing there is a fuel polishing system installed that serves as a transfer system between the main fuel tanks. I've yet to look into the specifics of the system but there are a couple of filters in the system along with the OEM Racors. The boat is from Southern CA originally and probably did some Mexican Riviera cruising hence the added insurance of on board fuel polishing system.

 

[dtfeld]

Have your friend get a membership for CSR.com and look at the Diesel Fuel Management write up done by Fwebster (Frank). It'll probably pay for itself right away.

As mentioned above, algae/bacteria can thrive/eat diesel fuel in the presence of water and the by product is a nasty slimy growth in the tanks. Left untreated, eventually this will clog your Racors and other filters, usually at the most inopportune time. If really bad you can do real damage to the pumps and injectors.

It might be possible to treat this DIY with BioBor and/or DeiselKleen Fuel and tank Cleaner (green label) and multiple filter changes. If the growth is extensive, calling in a pro may be necessary. They will do the same thing with a bigger set of pumps and filters to remove this contamination.

Once cleaned up, you need to follow Franks "recipe". It will reduce these issues going forward. I would guess almost all of us have had an issue or will sooner or later, so treating your fuel is a necessary part of owning a diesel powered boat.