Winterization - Fuel Storage - Empty Tank Approach

[tpenfield]

Prepping to take my brother's Grady-white with twin Yamaha 350's out for the season and get it tucked away for winter.

I was surprised to read this in the Yamaha service manual . . .
Conditioning and stabilizing gasoline
When preparing to store a boat for extended
periods (2 months or longer) it is best to com-
pletely remove all gasoline from the boat's
fuel tank(s). If it is not possible to remove the
gasoline, add one ounce of "Yamalube Fuel
Stabilizer & Conditioner Plus" to each gallon
of gasoline in a full tank of gasoline to pro-
vide fuel stability and corrosion protection.
TIP:
Do not fill the fuel tank(s) to the point of over-
flowing. Approximately 7/8 full will allow
enough space in the fuel tank to prevent gas-
oline purging from the fuel tank vent due to
expansion with temperature changes.
Do not cap the fuel tank vent. Excessive
pressure could damage the boat and motor's
fuel systems.
A partially filled fuel tank, less than 7/8 full
but not completely empty, is not recommend-
ed. Air space above the gasoline allows air
movement which can bring in water through
condensation as the air temperature chang-
es.
Condensation inside the fuel tank can cause
corrosion problems and phase separation of
gasoline containing ethanol.
Consult your Yamaha dealer concerning pre-
ventative measures that may work best for
the gasoline and environmental conditions in
your area.

I was surprised to see the 'empty tank' theory recommended in a service manual. I am wondering if there is a paradigm shift underway towards recommending empty tanks versus full tanks. What is interesting in their description of fuel storage procedures is that they do not correlate a completely empty tank and a partially filled tank as far as their concern for moisture retention. :noidea:

 

[alldodge]

Cold front moving in this weekend so I said the heck with it, I'm winterizing.

Last year I had a 1/4 of gas, this year I have a 1/2 tank and do not use stabilizer.

 

[oldjeep]

I leave exactly whatever is left in the tank and no stabilizer. Supposed to snow tomorrow so I'll winterize this weekend and call it a season.

 

[Fed]

About 40 Years ago I saw some snow, only a few small clumps on the side of the road about the size of cricket balls.
It was too cold to get out & touch it. :lol:

 

[rallyart]

^^ This is why Australia will never be a dominant force in Hockey...
(you can add an 'Ice' to that if you wish as they tend to do okay in the 'Field 'version)

 

[JimS123]

Ethanol, stabilizer, empty tank, yada, yada, yada. Pffftttt. You'd think boats were just invented in the 21st century.....LOL.

I have owners' manuals going back to the early 1950's. They all recommended stabilizer for Winter layup.

Grandpa insisted that the tank be full during the Winter to prevent condensation because that's what the marina told him back in the 1940's when he bought the boat.

Way back then even a little water in the gas was a catastrophe. Today, E-10 can solve many minimal problems because it will absorb the water and burn it. Back in the day we all used "Dry Gas" in the Winter because of potential freeze up due to condensation. That's one industry product that has been outdated.

BTW, Mercury Marine recommends the same procedure as listed above...

 

[Old Ironmaker]

Fill to the brim in November, add stabilizer, done. Never have had a problem with any of my gas powered toys and tools. Actually come to think of it I hadn't used the chainsaw in 3 years and this summer it started after some priming and a few pulls. To change now based on comments on the Internet would be foolish. Plus I know gas will be more this coming spring too.

 

[QBhoy]

Jeez...I totally understand the whole empty tank or full tank theory....but in all honesty I have left my tank at various levels over winter (in Scotland) and come spring time...never had a problem after servicing engine with all it involves.
Now....should I have a Diesel engine and be running on red diesel....it would be a different matter.

 

[ahicks]

Not getting in to the tank argument, other than to say I pay attention when we're talking a metal tank. Maybe not so much a 3/6 gallon plastic portable.

As far as stabilizer, there's no generic answers here. You have to pay attention to what you're talking about/thinking of. Gas mixed with 2 stroke oil, and gas that has not, need to be 2 different conversations, as the 2 stroke oil has a stabilizer in it, and anything running that seems to be pretty resistant to crudding up over just one winter. I have saws and lawn equipment that can and have gone neglected for years as well.

Straight inboard (automotive based) engines seem to be MUCH more forgiving when it comes to crap building up in their carbs, but they aren't totally crud proof!

It's the 4 stroke outboards that need to pay attention! A carb cleaning there involves several carbs as a rule, and that job can get pretty expensive by anyone's standards! The fuel injected engines not only plug injectors, but they seem to be going through fuel pumps as well! Love my 4 stroke, but I spent a LOT of time getting it right after is sat unprotected for a while previous to me getting it....

RE: oil injected 2 stroke engines, they almost always have multiple carbs. I think you need to pay attention here to. If one of those plugs up for any reason, you stand a chance of burning one or more cylinders down. To me, it just makes good sense to do what I can to avoid that scenario, and that's going to involve draining the carbs or running stabilizer through it.

My thoughts anyway, FWIW. -Al