6 month old mixed gas 85hp JOhnson

superharmonix

superharmonix

Petty Officer 2nd Class
Joined
Sep 5, 2010
Messages
140
The last time I fired up my engine was about 6 months ago. I've got roughly 3 gallons left, and there was ALOT of pressure in the tank when I took off the cap.
I did not add any stabilizer when I put it up for the winter.

My question is, would it be dangerous at 6 months to use the gas? Smells fine, external tank so I know there isn't any junk in there..
 
E

emdsapmgr

Supreme Mariner
Joined
Dec 9, 2005
Messages
11,551
Re: 6 month old mixed gas 85hp JOhnson

I wouldn't use 6 month old ethanol-blend gas in a 2 stroke outboard. The ethanol attracts water. I'd sample the fuel first to see if there is any water in it. If not, put it in your 4 cycle lawn tractor or mower-even with the oil in it. Mercury Marine prefers that you drain your fuel tanks in the fall at the end of the season.
 
Last edited:
superharmonix

superharmonix

Petty Officer 2nd Class
Joined
Sep 5, 2010
Messages
140
Re: 6 month old mixed gas 85hp JOhnson

I think I will just drain it then. I was going to add fresh fuel/oil to the mix and run with it.. I appreciate your advice. As I'm learning here, why is the water so harmful? Also, should I install a fuel/water seperator inline with the hose for good measure?
 
E

emdsapmgr

Supreme Mariner
Joined
Dec 9, 2005
Messages
11,551
Re: 6 month old mixed gas 85hp JOhnson

A fuel water separator is becoming more common with today's fuels. You engine was not originally setup for one. You need to be careful adding one. You don't want the fuel pump suction to increase too much, causing a lean running condtion to the powerhead. You can test the fuel suction with a gauge spliced into the line. If the gauge gets up to 7 inches hg vacuum at full throttle, it can run lean.
 
superharmonix

superharmonix

Petty Officer 2nd Class
Joined
Sep 5, 2010
Messages
140
Re: 6 month old mixed gas 85hp JOhnson

emdsapmgr said:
A fuel water separator is becoming more common with today's fuels. You engine was not originally setup for one. You need to be careful adding one. You don't want the fuel pump suction to increase too much, causing a lean running condtion to the powerhead. You can test the fuel suction with a gauge spliced into the line. If the gauge gets up to 7 inches hg vacuum at full throttle, it can run lean.
Click to expand...

Thanks a bunch!
 
You must log in or register to reply here.
Top