Hi

I just want to get to the heart of this long discussion.

I have 30 years of positive experience with a full tank and an additive for diesel. There was never water in the tank and organic pollution. Last year I was so smart not to do this because lack of wind had covered a distance of 1500 SM under motor and had refueled several times. The result after 2 months in the port with a 1/4 full tank and without Grotamar (additiv) in the diesel was a complete algae infestation of the tank and lines before the winter break and the refilling of the tank.

I can highly recommend filling the tank completely with the addition of a good additiv at every opportunity and before any longer standstill.

There was a great deal of effort in cleaning the tank and completely replacing the lines and the filter system.

Best

Arnold

SY Zephyr

SM203

Am 12.02.2020 um 01:45 schrieb Dan Carlson <carlsdan61@...>:

There is a third reason to keep the tank reasonably full.  As the tank gets closer to empty the sloshing of the remaining fuel at lower levels will begin to stir up that sludge cocktail at the bottom and it will begin to enter your fuel system.  You can see it in the Racor bowls, if may increase your vacuum gauge if you have it in the Racor and it can clog your fuel line.   

Last season another boater (non Amel) had engine trouble and changed his fuel filter. He then experienced air seeping into his fuel lines around the Racor connections.  In the end it turned out that was because his fuel line was so clogged.  He borrowed my suction fluid extractor and sucked about 20 liters of crud and fuel off the bottom of his tank before he had it clean enough to proceed.  When they were stopped they were not in a location with easy access to fuel polishing services.  He believes what broke it all loose was a very rough passage with low fuel levels.

Regards, Daniel Carlson on sv BeBe, sm # 387, currently in Cartagena

On Tue, Feb 11, 2020, 5:41 PM John Clark <john.biohead@...> wrote:

Hi Bernd,

     When I purchased SM37 in 2016 the previous owner stressed to me to always keep the tank full and to always use the Baja filter.  He said in the 16 years he had her no one drop of fuel went into the tank other than through the Baja.  He did two circumnavigations and claims to never have had an issue.  I followed his advice.

A year into my ownership, I performed maintenance changing out the Racor filter and the Volvo engine filter.  Both were clean.  I intentionally ran the diesel tank dry and used a boroscope to inspect the tank and found it also spotless.    I continued to use the Baja filter and also add a Biocide each time I fill up.  

 

 There are two reasons to keep the tank full, one is it prevents condensation from forming in the tank as temperature changes.  Gas expands and contracts with temperature and draws in moisture.  In a climate with daily temperature changes the cycle can pull in a notable amount of moisture after a period.  The moisture aids in the growth of bio-organisms that feed on diesel.   Second reason at least  for me in the Atlantic and Caribbean, is to have the ability to run from a hurricane at a moments notice.  Amels have large tanks which give them excellent range in a pinch I like to have that capability.

   Regards,  John

John Clark

SV Annie SM 37

Brunswick GA   

On Mon, Feb 10, 2020 at 10:13 AM Bernd Spanner <bernd.spanner@...> wrote:

Why fill up your tank to the max when you know where you want to go?

I think filling it up to the max only makes sense when you go for a really long passage and then you add some anti diesel bug adds.
When you fly on an airliner to your boat they only take as much fuel as they need plus alternate, contingency and a bit more for unforeseens.

--
Bernd
SN 119 / Cascais, Portugal

--
Arnold
SY Zephyr SM203