Diesel Fuel tank - fill or empty?

[SAWDOC]

Our usual routine is to top up the diesel fuel tank over winter in order to prevent condensation and water mixing with the fuel. This year we have cleaned out the tank which is currently empty in situ. Tank is now clean. Should I refill at this stage or leave it empty until we relaunch in April?

 

[dk]

Leave it empty with the filler cap open.

 

[Bosun Higgs]

Leave it empty and ventilated. Check for any condensation before filling in the spring.

The logic is that all diesel contains the bugs and some small amount of water. You dont get probs in car engines because of the turnover of fuel. So why fill your tank now and let the fuel sit there festering for 4 months.

 

[SAWDOC]

Leave it empty and ventilated. Check for any condensation before filling in the spring.

The logic is that all diesel contains the bugs and some small amount of water. You dont get probs in car engines because of the turnover of fuel. So why fill your tank now and let the fuel sit there festering for 4 months.

I see the sense in that. However the only ope I have is the filler cap and I am a little apprehensive about rain/water ingress if i leave it off- what about leaving the filler cap off on dry days? ie occasional ventilation

 

[Quandary]

Leave the cap on. before filling borrow vacuum cleaner and put hose down into tank (perhaps check with cleaner owner first? or use a bit of scrap hose) suck or blow for an hour before filling.

 

[SAWDOC]

Leave the cap on. before filling borrow vacuum cleaner and put hose down into tank (perhaps check with cleaner owner first? or use a bit of scrap hose) suck or blow for an hour before filling.

Good in theory - won't work in practice. Could use my Pela oil removal pump as an alternative.

 

[Jamesuk]

As for keeping the tank ventilated, would the overfill vent not sort this out?

 

[SAWDOC]

Thanks everyone for the responses. Having chewed over things for the morning, this is what I propose:
Leave the tank empty until April.
Week before lift in, run through say 10 litres or so of diesel which I will drain off again and filter/decant as neccessary
Fill tank.