Best Fuel (gasoline) additive for boat?

[DanL13]

I recently acquired an older fishing boat from my dad who has decided he’s too old to want to be a boat owner. For storage over the winter is there a preferred “best” additive? I’ve used Conklin Fuel Mate in the past in various machines, not sure if that stuff lives up to their marketing claims or if it’s just junk. I’ve used seafoam in things but not really with the intent of winter storage. Is Sta-bil my best choice? Something else? I’m open to suggestion. If it matters it has a 1996 Johnson two stroke that is oil injected. Boat has a nearly full tank, do I drain it out and store it close to empty or best to leave it close to full to help prevent condensation?

 

[fantastic]

Woops! You're looking for additives. I know the motor oil geek has posted additive video's you can check out. In the meantime here's some fuel stabilizers after 5 yrs.

F

Thread 'Project Farm fuel stabilizer after 5yrs.'

Oct 5, 2025

There’s some seriously interesting stuff here. I’ll say that I stocked up ordering a few cases of Stabil Marine 360. It has PEA in it. On Amazon it’s a steal at $7 right now but sometimes you can find it for $4 per 8pm bottle. I put it in the boats and my farm/work truck when it sits a while. But this video is pretty cool.

• FlyingTexan
• Replies: 32
• Forum: Fuels and Fuel Additives: Gasoline and Diesel

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[DanL13]

Woops! You're looking for additives. I know the motor oil geek has posted additive video's you can check out. In the meantime here's some fuel stabilizers after 5 yrs.

F

Thread 'Project Farm fuel stabilizer after 5yrs.'

Oct 5, 2025

There’s some seriously interesting stuff here. I’ll say that I stocked up ordering a few cases of Stabil Marine 360. It has PEA in it. On Amazon it’s a steal at $7 right now but sometimes you can find it for $4 per 8pm bottle. I put it in the boats and my farm/work truck when it sits a while. But this video is pretty cool.

• FlyingTexan
• Replies: 32
• Forum: Fuels and Fuel Additives: Gasoline and Diesel

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Actually this is very helpful. By additive I guess I actually mean a stabilizer for winter storage. I (incorrectly) use the two terms synonymously

 

[Ursatdx]

I've used regular Stabil Red for years without issue in several different boats/engine combinations.
Always fogged through carbs and plugs.
On the FI machines I use Yamalube EFI storage oil.

 

[97prizm]

I recently acquired an older fishing boat from my dad who has decided he’s too old to want to be a boat owner. For storage over the winter is there a preferred “best” additive? I’ve used Conklin Fuel Mate in the past in various machines, not sure if that stuff lives up to their marketing claims or if it’s just junk. I’ve used seafoam in things but not really with the intent of winter storage. Is Sta-bil my best choice? Something else? I’m open to suggestion. If it matters it has a 1996 Johnson two stroke that is oil injected. Boat has a nearly full tank, do I drain it out and store it close to empty or best to leave it close to full to help prevent condensation?

The Chicanic YouTube channel Swears by ethanol shield. She says that ope will start right up after sitting all winter. This is after she said they've tried alot of products over the years. Stabil makes a long-term storage product but I can't think of it. I think it's dark red and has a silver label?

 

[NiwradND]

my favorite is seafoam

 

[JRay’07]

How about some Johnsen’s fuel stabilizer for your Johnson?
https://www.johnsens.com/all/4690-fuel-stabilizer/

 

[DanL13]

my favorite is seafoam

I kinda question how well seafoam does as a long term stabilizer but I have used it in small engines and equipment that has done some sitting and running a little rough with pretty good success

 

[danthaman1980]

I've had great luck with the blue Sta-Bil (Sta-Bil Marine).
I treat 91 octane E0 premium fuel at about 1 oz/5 gal blue Sta-Bil and 1 oz/5 gal TC-W3 (usually Pennzoil XLF). Fuel treated this way will last at least 2 years, usually longer.

 

[MurkyAsparagus]

I prefer the Marine Stabil. It has an included fuel treatment as well as stabilizer. I tend to use it in all my power equipment, regardless if it’s marine or not.

 

[Mainia]

Stabil it is.

 

[SOUNDMAN5000]

Sta-bil and fogging oil is what I think I would use...

 

[JustinSL]

PRI-G

 

[Oldwolf]

I use Blue Stabil and no alcohol gasoline.

 

[FlyingTexan]

Stabil Marine 360 and order the 8oz off Amazon. Has pea in it as well.