Adding additives to fuel

DavidKnapp

Cadet
Joined
Jan 27, 2012
Messages
17
Got a 79 Johnson 140 ,mixing oil with the fuel ,is it ok mix additives to the fuel ,or is it needed ?
 

boobie

Supreme Mariner
Joined
Nov 5, 2009
Messages
20,826
Re: Adding additives to fuel

Mixing fuel stabilizer additives with the fuel is one of the best things you can do with this crappy fuel we now have. I'm sure more will chime in.
 

DavidKnapp

Cadet
Joined
Jan 27, 2012
Messages
17
Re: Adding additives to fuel

Father in la swears by it in his boat but his is fuel injected and has a oil mixing tank on his motor ,was'nt sure if it's ok carbureted system.
 

wired247

Lieutenant Commander
Joined
Oct 8, 2011
Messages
1,557
Re: Adding additives to fuel

Better to just buy real gas . You arent using much and it might be another $5 a tank for 92 octane straight gas. You'd pay about that much for whatever additives you'd use. Last tank of the year use some Stabil. Otherwise its better just to use real gas and 2 cycle oil.
 

toddschubert

Chief Petty Officer
Joined
Sep 3, 2011
Messages
504
Re: Adding additives to fuel

Make sure you use a 100% petroleum product like Sea Foam which I find to work very well.
Don't use anything with alcohol!!!!!!! Same as ethanol in gas....bad thing
 

tx1961whaler

Vice Admiral
Joined
May 31, 2008
Messages
5,197
Re: Adding additives to fuel

Make sure you use a 100% petroleum product like Sea Foam which I find to work very well.
Don't use anything with alcohol!!!!!!! Same as ethanol in gas....bad thing
Sea Foam is up to 20 percent isopropyl alcohol....
 

OutOfControl

Petty Officer 3rd Class
Joined
Nov 26, 2011
Messages
92
Re: Adding additives to fuel

"Sea Foam is up to 20 percent isopropyl alcohol...."

tx1961whaler is correct, about 15% iso. I make my own "SeaFoam" using diesel fuel(60%) and naptha(40%). I previously used the iso alcohol in the formula but eliminated it due to the ethanol issues. Also works good for cleaning the carbs and reducing carbon build-up.
 

HighTrim

Supreme Mariner
Joined
Jun 21, 2007
Messages
10,486
Re: Adding additives to fuel

There is no need for 92 octane, 87 octane is all that is needed.

I like to run either Sea Foam or Carbon Guard with every tank, your motor will thank you. A tank doesnt last me very long in the summer, so I only add the Stabil on the last tank of the year.
 

wired247

Lieutenant Commander
Joined
Oct 8, 2011
Messages
1,557
Re: Adding additives to fuel

There is no need for 92 octane, 87 octane is all that is needed.

I like to run either Sea Foam or Carbon Guard with every tank, your motor will thank you. A tank doesnt last me very long in the summer, so I only add the Stabil on the last tank of the year.


87 octane is swill. I literally wouldnt run that crap in my lawn mower. The alcohol will soak up water especially in a marine environment until the point it gets saturated and the water separates in the tank or in the carbs. In most markets in the US the only real 100% gasoline is 91 or 92 octane and even then you have to make sure its not an ethanol blend. Ive got a half dozen gas stations in town that sell real gasoline including the local marina ( $2.90 a gallon believe it or not ) . Yes. Theoretically 92 burns slower than 87 and if you dont need the octane it doesnt help you to use it but its not the octane you buy the 92 octane for. Its the lack of alcohol.
 
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