Which fuel stabilizer do you use?

[cragginshred]

Which fuel stabile do you use for winter? I filled my boat with premium fuel now want to treat it to keep it good. BG has some good products but did not know if I needed to drier for ethanol too?

[oldjeep]

None, ever. We store over 100 gallons of e10 in cars, boats, equipment for 6 months at a time. Just park them then start up when it is time to use. Your standard fuel stabilizers contain small amounts of naptha or propanol - stuff that is already in fuel in much higher quantities.

[bananaron]

SEA FOAM...........Great product that has many uses.I also use non-oxy gasoline in all of my boats motorcycles and small engines.Any other gas has a very short shelf life.

[PatM]

Ethanol Shield. You can get it at Home Depot. Recommended by my lawn mower dealer because it is "Organic" and does not have the chemicals that Sta-Bil and others have. Those chemicals can create as much of a problem as the ethanol.

[oldjeep]

Organic? The msds says it is 75%-90% butoxyethanol - so yes technically organic but basically the same stuff in other stabilizers.

LINK

 

[Wayne]

While I’ve had good luck with Sta-bil additives in various cars and sports equipment, our Malibu does not run well on gas treated with it. Doesn’t matter if it’s fresh gas or stuff from the last season. Causes a hesitation when you pulling a skier up. So I switched to the method of just running everything low on gas at the end of the season and fill up with fresh stuff at the start of the next season. Quite honestly I don’t notice any issues with this method and it’s one less thing to buy.

[Jmoski]

I've always run Sta-Bil 360 Marine - no issues firing up in the Spring after sitting for 4-5 months during winter.

 

I start putting stabilizer in the fuel in October as I never know which run will be my last. This way I know the fuel throughout the system has it. I also leave the tank mostly full to minimize the amount of air in the tank.

 

My friends older non-fuel injection boat is especially sensitive to old gas & getting moisture in there. Last winter he left it almost empty and then had a bitch of time getting her to run in the spring.

 

Condensation from the air in an empty tank as the temp drops is the source of the problems...

[eleeski]

I try to ski enough through the winter to keep the boat's fuel reasonably fresh.

 

California's long drought meant my diesel tractor wasn't needed to fix the road for several years. The fuel pump froze up. They recommend Sea Foam and some Marvel Mystery oil added to the diesel to protect the new fuel pump. But the fuel pump is a weak spot for my crappy Chinese tractor - at least the replacement was inexpensive. Probably because there are no timing marks so the installation is a pain. I'll keep you posted if we have a good winter and I need to start it after nearly a year of sitting with some Sea Foam and Marvel Mystery oil gumming up the diesel.

 

Way off topic but I have salvaged old gummy diesel by adding some gasoline to the mix. Worked fine. I don't think that ruined the fuel pump as it had several tanks (years?) of fresh diesel after.

 

Further thread drift, how about a diesel ski boat?

 

Eric

[PatM]

@oldjeep Notice the quotes on organic. Just listen to what my small engine repair guy tells me.

[ScottScott]

@wayne Can't argue with what has been working, but I've always heard to store with a full tank of gas. The large amount of air left in a tank can cause condensation moisture, that will get into gas. Fresh gas in the spring seems like a good concept, but the moisture thing is what I've heard is worse.

 

We're lucky enough to be able to run at least a couple times a month through the winter, so don't usually use any stabilizer. In theory I should be topping off the gas AFTER each use, instead of filling up on the way out to the lake so it doesn't sit 1/2 empty.

[A_B]

I have been using Seafoam, but trying Lucas this year.

If you use gas with higher ethanol content, it will not last over winter like the old gas use to.

Apparently, it corrodes stuff. I had a snowblower that I forgot to drain the gas in, and the carb was gummed up and would only run on choke. I had to rebuild and clean the carb or buy a new one. I bought a new one and it ran like a champ. Don't let that happen to a ski boat!

[braindamage]

Nothing. I use 93 octane no ethanol gas. I top it off come spring with same and haven't had any issues. I do this for all my seasonal engines.

[BraceMaker]

@ScottScott there is a lot of universal advise that exists that is based on history more than present tense.

 

Tractors/Motorcycles/boats/cars etc - for most of the time they have existed have had steel fuel tanks, these fuel tanks when vented to the atmosphere so that a carb can suck fuel from it using a mechanical fuel pump with out creating a vacuum will "breathe" in and out as the temps swing through out the day, in theory pulling in damp moist air that when the conditions are correct will deposit itself on the walls of the tank, condense into the fuel and rust out the steel tank. However - your boat has a plastic tank, when it storage you hopefully have it in some amount of climate control ie. Indoors out of the sun.

 

And... For everyone who is concerned about this do you not cover your fuel vent when you winterize?

 

For me as I near end of season I treat with the blue marine stabil, I then run most of the gas out of the boat, winterize and cover the fuel vent hole with a wad of silicone putty (or tape) in spring the boat gets a full tank of fresh fuel and never an issue. If I finish up the season with too much fuel in the boat due to weather etc I siphon it into my car and burn it up.

[Jmoski]

@BraceMaker - good question on the vent - my assumption is that it functions like a check valve, meaning it's one-way, if you overfill it or the plastic tank shrinks in the winter with a full tank it will spit out the excess.

 

If the vent draws air in - that would make me nervous as that means water could get in if I took a wave broad side?

 

It's the air that's already in the tank by virtue of not being full that has moisture in it that condenses when you drop the temperature from 70 to 0 degrees F.

 

Hence why I leave it mostly full.

 

If only I could get gas with zero ethanol!

[dvskier]

@Jmoski check pure-gas.org for locations that sell ethanol free fuel. You might be surprised to find a station nearby.

[Jmoski]

Looks like in MA I only see power equipment stores that sell small containers for much dinero...

[BraceMaker]

@Jmoski Its not a check valve on my boat - more of a breather - traditionally you would make a "loop" of fuel line between the tank and the breather to prevent fluid from getting to the tank and zip line that in place.

 

I'm not sure if these vents exist on boats that have fuel returns on fuel injected systems - they must have for fueling?

[oldjeep]

New boats have a more sophisticated vent system and evap canisters

[Wayne]

@ScottScott the amount of condensation that *could* form is not enough to be concerned about. If you have enough moisture in the tank to cause engine problems it’s most likely not from the condensation effect in your boats gas tank. It’s more likely coming from direct water intrusion through the vent or it came from where you purchased the gas.

[Bongo]

@ScottScott Similar to a couple of the above comments, but slight variance. The "leave the tank completely full" or completely empty is relating to a metal tank. Air warms up faster than the fuel and the tank. Damp air condenses into water on the cooler metal wall. Water deposits in the tank. Repeat many times over the winter. If there's no (little) air in the top, much less damp air to condense to water and so nearly as much dilution.

 

Since almost everyone's boat on this forum now has a plastic-type tank, the condensation is much less of an issue. Therefore, isn't a factor when diluted into 25 gallons of gasoline.

 

Now, shall opine whether batteries go bad on a concrete floor when you store them outside the boat? :-)

 

BTW, I've stored my boats in protected but non-climate controlled space in MN and MO for the past 25+ years. Never had a problem. But I do also leave my tank full and with SeaFoam when I think about it before putting away, and I do store my battery on a shelf (w/tickle charger) and not directly on a concrete floor. So even though I don't think it matters, I still follow ye' ol' protocols.

 

Bongo

[Jmoski]

The amount of condensation you get in the tank over the winter is a function of three variables: volume of air in the tank, amount of water vapor held in the air, and the % drop in temperature.

 

The ability of air to hold moisture is a function of temperature. The colder the air is, the less it can hold.

 

The metal tank is a problem as others mentioned due to rust. Yes, a metal tank will cool of faster, but at the end of the day once the tank & air inside reach equilibrium with the ambient temperature, the total amount of condensation is driven by the size of the temperature drop.

[skiinxs]

I'll chime in. I think the rule of thumb is that untreated gas loses around one octane point per month of storage, so I would start with 93 octane and treat it with sea foam or the Stabil that is designed for the crappy 10% alcohol gas. I wish I could get pure gas but it isn't available in my area, just hope the 15% alcohol mandate gets put down as the marine industry is fighting it and there are lots of online petitions going around. The hoses are better now, but I have still seen fuel lines swelled almost as big as a soda can from the alcohol in the gas. The biggest problem is that it tends to separate out during long periods of storage and you may be running on almost pure alcohol when that layer gets to the fuel pickup. It also absorbs a lot of water (which is why Heet can help get rid of water in your fuel as it gets it to mix with the gas.

[oldjeep]

We must get the magic e10 here. Only ethanol issues I have seen were related to either ancient fuel lines or the e10 cleaning up an old dirty fuel system and plugging a few filters.

[dvskier]

@oldjeep seriously that ethanol is crap in small engines Nd marine applications. Any marine mechanic and PCM will tell you that they do not recommend any ethanol in fuel. You may have manic in your fuel but I can assure that it doesn't work in the south. Why not just pay the extra $0.50 per gallon and live life without fuel related problems?

[oldjeep]

@dvskier I'm not going to convince you of anything but here is the state of things up in the great white north.(MN) E10 has been the norm here for more than 25 years. E0 is not a common thing, you can find some stations that sell it but they are few and far between. I have a 30 year old toro snowblower and a 20 year old Ryobi trimmer that have run on E10 for most or all of their lives, in addition to chainsaws, generator, pressure washer, snowmobiles and numerous boats, classic cars and jeeps.

 

E10 has less energy than E0 so on a carb engine that has been tuned to run lean (anything built since energy star was a thing) then you need to adjust the mixture a bit to make the engine happy on E10. The 2005 Mercruiser I had was the worst in this regard. Anything fuel injected couldn't care less. If you get significant water in your fuel then you are buying it that way or water is getting into the tank when it rains.

 

The snowmobiles I parked last March started right up and moved to the other garage 2 weeks ago, same as every other year. In the spring the lawn mower will fire right up on the first pull and the trimmer will take 30 pulls and some swearing before it starts.

 

In answer to your question, would I pay an extra .50 a gallon on the 500-1000 gallons of fuel I buy a year for non-cars to avoid a problem I've never had - Nope.