[jhhall]

I had several conversations over the past few weeks about whether to store our boat with the diesel fuel tanks full or 1/4. The boat will be in heated storage.  Those that say full is because it keeps the moisture out. Those that say 1/4 is to keep the weight down. Everybody says to put a biocide in.  Looking for additional thoughts.

[ReelMagic]

I've had a boat for more than 60 years and have always stored with full tanks w/stabilizer & biocide (for diesels). Not as concerned with weight as condensation when partially filled or nearly empty. Several marinas in our area will not allow you to store unless the tanks are full. Less of a fire hazzard as there are no gas vapors to explode. Have friends that never worried about filling their tanks until they started to have problems. All had the same issue with water in the fuel (gas & diesel)... Several had the fuel polished to remove the water which is expensive. One had to have the tanks (gas) emptied and cleaned (vacuumed) which cost a lot more..  We live in the northeast and store the boat for approx. 6 months....M2C

[clcapob]

I've always winterized FULL with biocide.

[abyss]

Topping off for sure. Cummins has recently stated they suggest no stabilizer to the fuel if you will use your boat seasonally. I’ve been doing that with no issues!