Fuel for the winter?

Fiat4Fun

Petty Officer 1st Class
Joined
Sep 14, 2009
Messages
215
Howdy, I have my 1986 CC with a Mercruiser Alpha One Gen One winterized every year. My mechanic puts in stabilizer for the fuel, and I have always filled the tank, all 60 gallons, with the thought that no water will get in if it's full. My mechanic thinks it's a waste, and the old fuel sitting in the tank for the six months with stabilizer is fine. The fuel I use is ethanol free, which is good on the old motor, but how does it hold up over time with stabilizer.

So, what do you think? Fill the tank, and put stabilizer in it, or don't worry about how much fuel is in the tank and just add stabilizer to it?

Any advice is greatly appreciated,
Thanks
Bob
 

JASinIL2006

Vice Admiral
Joined
Feb 10, 2012
Messages
5,524
There are about a million threads on this topic, and if you read them all, you'll find:

A. Lots of people stabilize whatever fuel they have.
B. Lots of people fill the tank, then stabilize it.
C. Lots of people do A or B, but without the stabilizer.
D. Lots of people leave as little fuel as possible in the tank.

All of these approaches seem to work fine. There may be some issues if the layup is much longer (a year or two), but you don't hear of many problems from seasonal layup using any of these approaches. Personally, I only can find fuel with ethanol. I use stabilizer and forget about it. I don't know if the stabilizer makes a huge difference or not, but it doesn't cost much and it makes me feel better.
 
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Starcraft5834

Lieutenant Commander
Joined
Jun 2, 2013
Messages
1,677
What JAS said.......I would only say.. put a stabilizer additive in... how much fuel does not matter... if it's a seasonal storage, folks that use no stabilizer probably have little or no problems either....very long storage causes most problems... I dumped the rest of my fuel treatment in my tank before my last float...ran it thru, Im good,, pay more attention to proper winterization of engine and drive... "air dont freeze", dry storage= only sure way that your block wont crack..
 

HT32BSX115

Supreme Mariner
Joined
Dec 8, 2005
Messages
10,083
Well, You could just leave the tank empty or nearly empty and be just fine or do like I have done for the last 20 years or so, leave the tank approx 1/4 or less and put NOTHING in the fuel. Mine sits from the end of AUG to JUNE every year and I don't put special sauce snake oil in the gas. Read the following and make your own choice. http://www.yachtsurvey.com/myth_of_condensation_in_fuel_tanks.htm
 

stonyloam

Vice Admiral
Joined
Mar 13, 2009
Messages
5,827
I'm with HT, I use non ethanol, and just put it away with whatever is left in the tank. No stabilizer (use it if you like) no fogging. Contrary to what a lot of folks think, the space above the fuel in the tank is NOT filled with air, it is filled with GASOLINE VAPOR, so you are not going to get condensation over the winter.
 

Volphin

Lieutenant
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Jun 5, 2011
Messages
1,405
I typically use a stabilizer, but gas loses octane in storage anyway. This year I may remove it and pump it into the SUV. LOL
 

HT32BSX115

Supreme Mariner
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Dec 8, 2005
Messages
10,083
The biggest problem with long term storage of gasoline in an un-pressurized container is the loss of the lighter components.

They simply evaporate off. It's not as bad as it used to be since the vapor pressure ("today") is lower than than in the past but it still happens. Cool or cold weather slows or reduces it but doesn't stop it........and there is NO snake oil that can prevent it.

The only way to prevent it is to have a completely FULL container that is sealed and pressurized at the actual vapor pressure of the fuel (which is dependent on temperature)

Just about ALL marine fuel systems are vented to "atmosphere" so you can't "store" gasoline in the tanks for long periods (years)

Since it's pretty clear that water intrusion due to condensation is minimal or non-existent, [see http://www.yachtsurvey.com/myth_of_condensation_in_fuel_tanks.htm ] You're "better off" draining the fuel if you can or putting the boat up for storage with as little fuel as possible.

I have done this for as long as I have had boats. 30+ years. I have never used any sort of "stabilizer".

I also don't bother trying to find NON-ethanol gasoline either.....I know some do and I don't "dog" them for it, I just don't think it's worth my time to go searching. Every year I just fill the boat up in June or so and use it all summer. I have sometimes gone as long as 2 years on a fuel filter.

According to the guy at Yachtsurvey, his experience with water intrusion turned out to be from either the fuel itself(contaminated) or leaky fill-caps, vents, etc.....

NO amount of snake oil can prevent water intrusion and fuel "driers" ARE alcohol. So for those of you that use NON-alcohol fuels and THEN put a fuel "drier" in the gas, aren't you just adding to your fuel the very stuff you are trying to avoid?

I store my boat INSIDE here in the NW. It usually rains all winter (and sometimes all summer!!:mad-new:) BUT the boat is always INSIDE.)

If I stored my boat outside all year, And I suspected water intrusion, I would remove the tank gage sender and suction the remaining fuel out every spring so I could remove any water that might have leaked past the cap or via the vent etc.....

ymmv,



Rick
 

Watermann

Starmada Splash of the Year 2014
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Jan 12, 2013
Messages
13,747
I winterize by block draining / take off all hoses, change gear oil, change engine oil, remove the out drive to check for water, grease U joints and put it back together. Never have worried about the fuel and I too don't believe in adding anything to the tank. I have a station near me that offers non corn juice premium and that's all I use in my boats and small engines. Come to think of it, I'm about the only thing around my place that ingests ethanol regularly. :D
 

Lou C

Supreme Mariner
Joined
Nov 10, 2002
Messages
11,798
I agree with some of the thoughts here, I've had this boat 12 years, its always stored outside, every year all I have done is stabilized whatever amount of gas left and in the spring, I take off the fuel filter, dump it out and look for water. Never seen any. And this is with E-10 gas. Make sure that:
Your deck fill gasket it good. I replace the Perko gas caps about every 4-5 seasons
That your sending unit gasket on the tank itself is well sealed and that water does not run on top of the tank and sit there.
If you get a lot of water, it is coming from the gas station or those 2 sources.

It is possible to get some from condensation. We have a small Suzuki DF 2.5 outboard stored under the back porch. Once I did see a tiny bit of water in the bottom of the tank, but this one has a nice drain on the carb. I drain the carb and you can actually just tip the OB to the side to drain the tank. I have 8 other small engines and I don't drain any of them. I use stabilized gas in them all and they all usually start well.
 
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