Full or empty fuel tank this winter?
 

Is there a general consensus with this? My local marina wants my small outboard Grady-White as empty as possible with Stabile in whats left. Thats gas with ethanol. Some guys say fill it up. How about ethanol free ? Same guidelines? Five months of sitting.

I used to be in the "leave it full" camp but now with ethenol in the fuel and the fact that it separates in storage that long I have for the past several years run the tanks down as far as possible, added Stabil and in the spring fill with ethenol free and add some of that Starton blue stuff . THe fact the the ethenol based fuels separate is bad enough but on older boats and motors it eats some rubber parts as well so I like to keep it to a minimum.

I park my Grady in the boathouse with non-ethanol fuel, no additive, and what ever quantity it has in the tank and it sits for 7 months.

In the spring, I just start it.

I do the same with my Donzi.

No issues for the past 4 years...however now that I have posted this.....

Ken

I'm in NE too. 5 months totally fine either way with Stabil.

I have it zero'd down to where I run into fuel related issues, if it happens, over 8 months. Predominately , boats around here is stored outside. Shrink wrapped.
If you are concerned, drain fuel in spring and put it in to your truck or car. Fresh gas to the boat.

I have an electric pump set up (mucho ft of rubber fuelline both ends, electrical many feet of wire with alligator clips to hook to battery or battery pack)I use to do this....boats, sleds, pwc's...you name it.

I leave it mostly empty, my final time out I add seafoam at ~1oz/gallon and make sure I get the secondaries open to get it through the whole system then store it. Usually one can or less.

Probably don't even need to do that as I run non-ethanol gas, but if nothing else it makes me feel better :)

I start adding Sta-Bil (blue) around this time of year and the tank level ends up where it ends up. Top off in spring. Never an issue.

Seafoam in the fall to half tank or less, add five gallons of race gas in the spring + top up.

There is no issue with going empty. Go ahead and drain it as best you can. With an outboard this is pretty easy by hooking up an electric fuel pump for less than $40 bucks from Advance auto or similar. Just make sure that whatever goes through the motor last during your winterization process is stabilized.

You do NOT want to mix ethanol fuel with non-ethanol fuel; to try to "whittle down" the ethanol content by adding non-ethanol fuel.

Gasoline loses octane over time. I leave my stuff empty in the winter and fill it with fresh fuel in the spring. Never had an issue.

Diesel on the other hand will condensate in the open air. Fill the tanks up as full as possible before you put it away.

With ethanol- I used to fill it up and treat it til two years I had 30 gallons go bad and separate after sitting 5 months. Pain to dispose of. Now I keep tank as empty as possible and treat it heavy. This is in MD.

Non-ethanol- Try to get tank down past half and treat it. I leave a boat in NY stored 7 months like this every year no problems.

I now think if the gas does go bad...what's easier to get rid of...a little or a lot?

I leave mine full of non-ethanol with stabil, it stays in my heated shop if that makes a difference and doesn't go unused for more than 5 months during the winter.

I prefer to just keep mine in Florida through the winter and use it. It's a great way to keep the gas from going bad. :boat:

Me too.

I used to do the full tank thing. But, I noticed that if you get some real warm temps during the winter, the fuel expands and comes out the vent.

Now that I have OB's, I'm debating about actually winterizing.

I leave as empty as possible and use the Stabil 360 (which is what others are referring to as Blue) which supposedly lets off a gas/vapor that is supposed to protect your tank... It has worked well for me over the past 2 years so I see no reason to deviate from it. And I use pump gas (E10). Mine is indoor stored and kept at around 50* all winter..

Why, please?

Padraig

My first year with a boat - 1976 - we filled the tank to the brim with a stabilizer for winter storage. The next season had nothing but gas issues. From that day forward we left the tank(s) almost empty and have had ZERO issues with fuel, dirt, etc.

I really try to keep the tank as empty as possible when it goes in for storage - however, I still dump a stabilizer in the remaining fuel.

First thing in the next season is fill the tank up and run the snot out of it!!

3pointstar

I've read a couple articles both ways about it, but a couple of marine mechanics have told me to avoid it. It's also been mentioned on here before.

This will be my 13th year with the same procedure on the Fountain. Approx. November to April. Boat kept in a covered shed. We use the other boats year round.

1) Run out gas to 1/4 or so at end of season. If more than this left use it in the cars since some might be several weeks old.
2) Fill to top with 93 octane and full dosage of marine Sta-Bil.
3) Use bilge heaters.
4) Ignore until April.
5) Change fuel filters and off we go.

If you mean mixing the two fuels , some have said they can cause precipitate to form and cause problems.

Non Ethanol 91, run it down to about 10 gallons on each side. I put blue stabilizer in the fuel along with seafoam. Then I pull the fuel and water separator and put 3-4oz of 2 stroke oil in there. I run the boat for a minute and shut her off so I coat the cylinders with oil. Works as a good fogging for the cylinders. In the spring, I run the boat for a quick run and try to burn about 5 gallons off each side, quick ride and then change the fuel and water separators and fill the boat up with 91 non ethanol fresh gas. Have had no problems, and I have owned 8 powerboats and some outboards too

When I unknowingly filled up with Ethanol fuel (it was marked as Ethanol Free) at a marina in FL; and left it in the boat for the remainder of the winter...
...upon first fire up in the spring; it ruined my all four of my fuel filters/separators; AND my fuel pumps (very expensive). As such, I am very cognizant of which fuel I get, and to ensure it's (over) treated with Star-Tron.

Have owned a boat since '98. We've had gasohol and E-10 around here as long as I can remember. Never had a fuel related problem with any of my 4 boats. I try to buy non-Ethanol when I can but all the road stations that carried it are now gone with the exception of the new Hy-Vee they just put in (91 octane is ethanol-free). My marina is ethanol-free but he is $1.50 over what you can buy it for on the road so I normally pull to fuel up. I think if you roached your fuel pumps and filters on a tank of gas there was something else in that fuel in addition to ethanol. Most of the guys on my dock fill up every October with E-10 and I've not heard of one issue come the following spring. This is everything from stock black motors to built-up blue motors both carb'd and fuel injected. Quality and freshness of the fuel play a big role in this IMO.

I always wonder here when you never see anyone buying the ethanol free gas how old it is. Old non ethanol also is not good.

I don't have to worry about storage anymore but always run seafoam anyway. Seems the inlector guys like it so I mix it in with almost every tank.

Everyone has their own opinion obviously. I say Bone dry empty and remove the gas caps ( so any moisture can evaporate) I don't start the season with 200 gallons of old gas. And any water would be on the bottom of the tank anyway so it would get through when you are just starting it up.

Ditto. Whats left in the tank doesn't bother me, as long as its treated properly.

I'm not sure I understand the removing the gas caps. Is moisture not able to evaporate through the tank venting system/overflow?

I used to fill with non-ethanol every fall. After draining 75 gallons to replace a fuel tank this spring, I'm running it low and siphoning the rest off to be used in the cars. It was a royal pain to drain, I ended up giving about 15 gallons to a neighbor just to get on with my project, and all gas gets old and loses octane. It's another 600lbs of weight on the trailer, too. So my prediction is an apocalypse/natural disaster will occur sometime after November when I don't have a full boat tank as a reserve.

actually i believe the octane never changes, its the volatiles that lose their properties.

eth land and non eth marine fuel have additives that do not mix well together, they can turn into a sludge like slurry

I think more air would be more evaporation . A test would be 2 burger king cups. One without a lid and one with a lid and a vent size hole cut in it . I believe the larger opening would evaporate better

http://www.boatus.com/seaworthy/SeaApr10Ethanol.pdf
First line, first answer of this article. I'm just going off the lies I've been fed by the marine industrial complex. Clearly it's a conspiracy to sell fuel additives and extraction devices!!!!:lolhit:

I pump mine bone dry - it won't be any good for anything other than your lawn mower next spring.

Got my info from an old thread on octane :cool:

Good article, ive often been a bit skeptical of the empty method for the reasons listed.

I drain the fuel tank with an elec pump and dump the fuel filters. Mix up 10 gals of AV gas (110LL), 1 quart of 2-stroke oil and an appropriate amount of marine Stabil, pour it in the tank and idle the engs until they start smoking.

Some people say empty some people say full so I just leave 1/2 tank. Makes everyone happy I think :bunnydance:

2004 Mercruiser in a Sea Ray that sat outside and has not ran for 5 years again sat out side completely for 5 years untouched. I winterized back then 5 years ago, Half tank of fuel of E 10 left in for 5 years with the soup mix and the soup mix in the gas tank for 5 years, winterized - Nov 2011- Fuel side just Drained gas tank completely, new fuel rubber line from tank to inlet side of engine, all new filters, fresh gas, primed complete fuel side and carb, engine started on the first crank, Runs great on the water hose for 20 mins straight. Will see how it runs on the water ( loaded ) this weekend. Did not even touch the carb yet.

IMO 20 to 50 % full of gas with soup mix - in the gas tank up to 6 month old gas and you should be decent to go for non performance engines. But in my stuff I drain that 20 to 50 % gas out and start out with fresh fuel for the season. It a piece of mind.

If you leave the tank empty in which is never 100 percent completely empty because the pick up tube is 3/8 inch from the bottom of the tank and some even a tad more away - I have seen some a inch away. With that said, gas evaporates and forms deposits / varnish in the bottom of the tank over time. So when you put fresh gas in when ever down the road - the washing machine effect in the gas tank while driving or towing the boat breaks up those formed deposits in which lift off - then run thru your fuel system. This is why you leave a min of 20 percent gas still in the tank and do NOT allow a water source to enter. GAS CAP seal and or its O ring is extremely important along with fuel vent.

Actually more deposits form from NON ethanol gas as its evaporates compared to E 10 gas. Why - because E 10 the ethanol is a cleaner and or acts as solvent - just like rubbing alcohol. ------ If you ever had a very varnished up gas tank one of the cheapest and easiest ways to clean it, is fill it up with straight ethanol - let it sit for about 4 days plus tow the boat around a couple of times - then drain the tank completely. It will clean the hell out that gas tank. Try it as I have for the past 10 years. Also ethanol has a very high octane rating. FYI something like 112 or 118 octane.

For Non ethanol fuel put in a clear jar with holes in the lid for a year or 2, it will shock you of the crust that forms. Ask me how I know. E 10 gas did not form any layer crusts like the Non ethanol. I am not pro or con for either fuel. But the key is how you treat fuels when they sit for periods of time. That's the key along with fuel samples especially at the beginning, middle and end of the boating year. Also ALL new fuel filters min. once per year..

Now I'm really confused!

Bup, what do you like as a gas stabilizer?

Padraig

It just seems risky to me. In that a large opening - or two or three - to the gas tank would allow critters, other fluids, etc to crawl/get in there and cause more issues. The only fuel issues I've had, have been ones I have caused.

That is a good write up. Interesting comment about stabilizers.