Portable fuel polishing units

[chuck53]

RichH,
Good comments. Thanks.

[RichH]

Probably not.
Such deposits begin as living colonies with natural 'adhesives' to help them 'stick' to the surfaces. Its when the cells die and break off from colony or when large portions of the colony breaks away is when the 'trouble' begins. You really have to visualize to be sure of the complete removal; otherwise, its just a 'guess'.

You can use chemical tank cleaners such as: Star brite - Catalog - Product Detail .... but unless you direct visualize, you can never be 'sure'.

To lessen and minimize contamination: keep the MINIMUM amount of fuel in your tank; dont always 'top-off' as there is NO BENEFIT in storage of 'old' fuel; diesel and gasoline have relatively short 'shelf life' when in contact to atmospheric air); use 'fresh' fuel (from a high-turnover 'truckstop', etc.); drain/empty the tank when the boat is not being used for looooong periods such as winter storage.

BTW - Atmospheric water 'equilibrates' or 'saturates' into fuels (typically through the tank vent); the less amount of fuel - the less water 'uptake'. ;-)

[drgtmartin]

NewportMike,

Who did you use to clean your tank? Would you recommend them?

Thanks,

Greg

[noelex77]

Originally Posted by RichH

Do NOT put an onboard recirculation polisher in/on the main fuel delivery system or its return line.

;-)

My fuel polishing system runs for several hours a day and I now have crystal clear fuel. The polishing system picks up from the bottom of the tank via its own pump, filter and line, but it returns via the diesel return line. I am curios why you consider this is a wrong ? I cannot see how it would create any problems.

The polishing system is only run when the main engine is off, if this makes a difference.

[RichH]

By putting a recirc. filter in the injector discharge/return line, you change the parameters of the injector return pressure ... increasing pressure in the return line due to the pressure drop of the filter when clean plus accumulating flow resistance as the filter becomes 'loaded'. Such can cause an increasing 'rich' mixture for the injectors, in comparison to a discharge line that operates at essentially atmospheric pressure.
Since your system 'works', let it alone; but, if you later experienced a much high fuel consumption, this may be the cause -- recirc. FILTER becoming plugged with corresponding higher back pressure on the injector discharge line.

;-)

[noelex77]

Originally Posted by RichH

By putting a recirc. filter in the injector discharge/return line, you change the parameters of the injector return pressure ... increasing pressure in the return line due to the pressure drop of the filter when clean plus accumulating flow resistance as the filter becomes 'loaded'. Such can cause an increasing 'rich' mixture for the injectors, in comparison to a discharge line that operates at essentially atmospheric pressure.
Since your system 'works', let it alone; but, if you later experienced a much high fuel consumption, this may be the cause -- recirc. FILTER becoming plugged with corresponding higher back pressure on the injector discharge line.

;-)

Thanks for the answer, but I don't really understand it. The polishing filter is not in the return line. If the polishing filter was completely blocked the engine return would work normally.
The polishing system picks up from the bottom of the tank, to a pump, then the polishing filter. The polishing filter returns diesel to to tank via a T connection on the return line which is between the engine and the fuel tank.
The engine has a separate fuel pickup and filter, but there is only one return to tank which is shared by the engine and polishing system.

This is a common way of plumbing a polishing system.

Perhaps you are only warning about placing the polishing filter actually in the return line so all the engine return fuel has to go through this filter. This is different to engine and fuel polishing system sharing the return line. I can see how the former plumbing would cause a problem, but I have never seen a polishing system designed like this.