Fuel Question - Full or not ?

[SNye45]

I recently bought a 20 ft Thunderjet with a 115 hp O/B. The dealer suggested that in the summer I fuel up on the way to the lake (to avoid evaporation while parked with a full tank ) and fuel up on the way back from the lake at other times.

Question - is there an advantage of starting a short boat trip always with a full tank (apart from running out -of course). Is this a matter of the balance of the boat ? or something I haven't even thought of. My boat holds 48 gallons and I can't imagine I'd use all that in 2 hrs of boating.

Any insight would be welcomed. Thank you

 

[jay_merrill]

Re: Fuel Question - Full or not ?

I think that most would say that the major issue is condensation leading to water accumulation in your tanks if they are left partially empty.

 

[Solittle]

Re: Fuel Question - Full or not ?

You could pick up some water through evaporation but if you have a water seperator/fuel filter (and I hope you do) it should take out any water. So the pureists will advise you to leave the tank full and they are right.

As for me my tank is 122 gal and I rarely use more than 30-40 gal per trip. With that in mind I could be carrying around 80 gallons more than I need. 80 gallons is weight not only sitting on the trailer but in the water for my engines to push. If fuel weighs around 6 lb/gal that is getting close to 500 lbs. I "normally" put in 25-50 gal when I get between 1/2 & 1/4 of a tank.

 

[SNye45]

Re: Fuel Question - Full or not ?

Sorry - I should of added this to my question at the beginning - Yes my boat does have a fuel/water seperator.

Thank you for you input so far !!

 

[Silvertip]

Re: Fuel Question - Full or not ?

Other than the weight issue, how long between uses will determine whether or not you should keep the tank full. Air is the enemy. That and lack of a fuel system additive like SeaFoam or Stabil, especially if you don't use the boat much. If you use a lot of fuel and the boat doesn't get much rest, there is absolutely no problem with leaving the tank nearly empty for a bit. The may not be advised if you live in a coastal area however.

 

[tommays]

Re: Fuel Question - Full or not ?

Well there is full and FULL i find that if i make it FULL on a 75 deg day that on the 90 deg day i will have a driveway FULL of FUEL

Tommays

 

[Silvertip]

Re: Fuel Question - Full or not ?

Well --- maybe not quite THAT full.