Fuel tanks - full or empty for the winter?

[Vince_nj1]

Ok, so my friends and I had a difference of opinion over the weekend on how I should handle my fuel tanks for winter storage. I was of the opinion, that I need to fill them to minimize the amount of air (and therefore water) that the gasoline will be exposed to.

One friend felt that I should leave them as empty as possible and treat them with fuel stabilizer and then get a fresh tank of fuel in the spring. He felt that fuel mixed with Ethnanol has a shelf life of only 3 months if untreated and a max of 6 months if treated with stabilizer.

My other friend added that I need to find Fuel stabilzer specifically designed to treat fuel mixed with Ethanol.

So right now I have a little over 1/2 tanks of fuel, not sure if Ethanol was mixed with it (120 gallons) and enough "Sta-bil" to treat 240 gallons.

So what do you think? Full or Empty? Will Sta-bil do the job or is there some other magic potion that I need to find?:huh:

 

[Sorrento 25]

I always added the appropriate amount of StarTron for whatever fuel I had remaining, filled up in spring, and never had problems.

 

[Still LauCo]

I don't want too much weight, so I keep it less than half full and treated with StarTron as well... Never had a problem.

You will most likely get all kinds of responses, so do what you feel is right!

 

[Vince_nj1]

I don't want too much weight, so I keep it less than half full and treated with StarTron as well... Never had a problem.

You will most likely get all kinds of responses, so do what you feel is right!

I'm going to keep the boat in the water this winter. (first time for me), so I'm not worried about weight. However I did read in the SeaRay owners manual, to keep the tanks empty to reduce weight when lifting the boat or blocking it..

 

[hack4alivin]

This is a very timely post as I was going to ask the same question.

I recently read an article on this very subject. The main point of the article (which got into detail) was the limited amount of condensation the fuels tanks will receive over the winter is very small. Their point was the fuel quality will degrade over time making the quality of the fuel in the “Full Tank” worse on the engine than the little bit of condensation received on an empty tank.

Here is the link, scroll down a bit to fuel tanks: :http://www.yachtsurvey.com/winter_lay_up.htm

 

[SeaHarley]

I split the difference.....
I try to gauge it so I end up with 3/8 to 5/8 of a tank on each side.

That way I'm only 1/2 the air space.... and 1/2 the old fuel.
I fill up when I launch which takes care of the old fuel.
And I've not yet had any water problems.

 

[osd9]

The amount of water from condensations may not be as bad as the condensation itself laying on the inside walls of the tank and causing 'corrosion/pitting' on the inside walls of the empty tank.

I always store(d) full, gas or diesel, and treat/stablize the fuel. In the spring, AFTER I run out the winter tank, I change the fuel/water seperators and filters.

There are a few other considerations to keep in mind depending on when you fill last and when you expect to fill again.

Say for example that you leave the tanks empty. Then, you put-in early spring to get a jump on things. You run to the marina and fill your tanks. Was that fuel at the marina sitting there all winter....untreated....condensating????

By the time I run out my 'properly treated and stored' winter fuel, there is a good chance that the local marinas will have taken on fresh supplies to replenish there winter fuel.

 

[hack4alivin]

There are a few other considerations to keep in mind depending on when you fill last and when you expect to fill again.

Say for example that you leave the tanks empty. Then, you put-in early spring to get a jump on things. You run to the marina and fill your tanks. Was that fuel at the marina sitting there all winter....untreated....condensating????

By the time I run out my 'properly treated and stored' winter fuel, there is a good chance that the local marinas will have taken on fresh supplies to replenish there winter fuel.[/quote]

Good point.... I know when I splash the boat in April the fuel I buy will be what is left over in the Marinas tanks from last season.

 

[Vince_nj1]

Ok.. I think that clears up everything... I will top off the starboard engine and leave the port empty :smt101 :smt038 :lol::smt043.



On a serious note, I think I may leave them 1/2 full, add stabilizer and plan on topping them off in the spring which will sort of hedge my bets... Who knows, maybe fuel will be cheaper in the Spring..

Besides I dont really have a way to empty them without driving around for no good reason.. I guess in the end, my decision is not to top them off.

 

[hack4alivin]

Ok.. I think that clears up everything... I will top off the starboard engine and leave the port empty :smt101 :smt038 :lol::smt043.



On a serious note, I think I may leave them 1/2 full, add stabilizer and plan on topping them off in the spring which will sort of hedge my bets... Who knows, maybe fuel will be cheaper in the Spring..

Besides I dont really have a way to empty them without driving around for no good reason.. I guess in the end, my decision is not to top them off.

I hear ya…. I read points for and points against.:huh:

That’s why I would like to hear from other owners what their thoughts are on the matter. At this point I think I am not going to fill the tanks.


Anyway, maybe you are correct with the gas prices, but then they’ll figure out some other excuse to raise them again.:smt013

 

[osd9]

....On a serious note, I think I may leave them 1/2 full, add stabilizer and plan on topping them off in the spring which will sort of hedge my bets... Who knows, maybe fuel will be cheaper in the Spring..

This spring, '08, the best investment in my entire portfolio was the fuel I put in my tanks the fall of '07.

 

[Jersey Mike]

Startron & stabilizer, 3/4 full. Haven't had an issue as of yet (8 year old boat). A friend of mine is still using fuel from spring of '07 treated the same way. He is finally close to empty, the last time I spoke with him he is storing close to empty for the first time.
Just a side note...check the o-ring on your fill cap, I've seen bad one on occasion.

 

[Skuza]

Keep in mind what can happen if the fuel expands in the tank and desides to overflow down the side of between the hull and gelcoat. Nice staining. We have always left ours around 1/2 to 3/4 and sometimes used Stabil. No problems under both circumstances. I think if this was really so critical you would hear alot more about it.

 

[Alex F]

I always keep my tanks full for the same reasons Dominic has explained. I also add Sta-bil http://www.westmarine.com/webapp/wc...eId=10001&Ntk=Primary+Search&ddkey=SiteSearch

I make sure the chemichal gets through the system by running the engine for 20-30min at idle speed only. This can be done by making your way to the lift (when geting haul out) and/or during the oil change process.

I've done this for the past 10 years with all of my boats. The only difference is the chemical due to the Ethanol. I've used EZ-to-Store (http://www.westmarine.com/webapp/wc...&storeNum=5000&subdeptNum=4&classNum=555prior
before Ethanol was introduced.

 

[Bridog]

"Almost" full with stabilizer. I was told to leave out some gas for expansion.

 

[Alex F]

This spring, '08, the best investment in my entire portfolio was the fuel I put in my tanks the fall of '07.

+1 :grin:
I filled mine in FL (fall 2007) at around $3.70. Last weekend paid $4.10

 

[Vince_nj1]

I found this.. Very helpfull...

http://hawaii.gov/dbedt/ert/new-fuel/files/boat-CTarticle.pdf

 

[Vince_nj1]

I think I found the answer.. This is from Mercruiser's winter storage proceedure: If the fuel has alcohol in it.. store it empty.. If the fuel does not have alcohol.. store it full.

Preparing Power Package for Storage​

1. Fill the fuel tanks with fresh gasoline (that does not contain alcohol) and a sufficient
amount of Quicksilver Gasoline Stabilizer for Marine Engines to treat the gasoline.
Follow instructions on the container.
2. If the boat is to be placed in storage with fuel containing alcohol in fuel tanks (if fuel
without alcohol is not available): Fuel tanks should be drained as low as possible and
Mercury/Quicksilver Gasoline Stabilizer for Marine Engines added to any fuel
remaining in the tank. Refer to​

​

Fuel Requirements for additional information.​

 

[skolbe]

My marina always has old fuel from the previous season.

 

[Bridog]

I remember when the ethanol thing started. Everyone was worried that the gas was going to destroy the gas tanks, engines, etc. I'm glad I haven't heard too many horror stories. I'll listen to my dealer's mechanic and store it full.