disposing or 2 cycle gas?

May 23, 2016
1,024
Catalina 22 #12502 BSC
Nearing season's end, time to get rid of older (4-6 months old) 2 cycle gas mix from outboard tanks, 3-6 gal. perhaps. Safe to dump this in your car's tank or not? (pita to dispose of otherwise in some areas)....thoughts?

(typo, subject should read disposing OF, not OR)
 
Sep 15, 2016
835
Catalina 22 Minnesota
A little at a time to a full tank won't hurt at all. That being said some counties around me take old gas for free. They even have old fuel jugs you can borrow to put it in. You might want to check with your county. Last time I did this for a friend we got rid of over 30 gal of bad gas from a speed boat.
 
Nov 6, 2006
10,087
Hunter 34 Mandeville Louisiana
I wouldn't use it in a car that has a catalytic converter.. a lawnmower or other small four stroke without a cat converter would be fine.. Some of the additives in the oil can accumulate in the cat converter and slowly kill it..
 
Mar 20, 2015
3,236
C&C 30 Mk1 Winnipeg
Some of the additives in the oil can accumulate in the cat converter and slowly kill it..
Yup.

I carefully use it to start fires in the backyard firepit with wet wood.

My buddy uses it to clean his garage floor ! :yikes:

Edit: "Scared" emoticon added for clarity
 
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Mar 20, 2015
3,236
C&C 30 Mk1 Winnipeg
I wonder what your ex-buddy’s insurance company would think about that after the explosion and fire!? (Electric door ?)
Exactly my thoughts. Not to mention inhaling fumes.
Goofy thinking IMO.

Admittedly it's usually badly deteriorated by the time HE uses it, so it's flash point is low.
(I tested some once to prove a point to him. It was very yellow, it burned more like kerosene)
I suspect the garage is not insured anyhow. Fortunately it is on acreage, far from any neighbours.



FWIW, using it for starting bonfires is dangerous if you don't have some brains. Take it from a former professional pyrotechnician, who prevented a birthday boy, from making a big mistake at his party with a big bonfire. Drinking + fires + fuel + lack of knowledge... definitely does NOT mix.

But heck, lots of people are idiots with gas BBQs too. Unlike what I see today, I seem to come from the last generation that was required to use what brains they had.
 
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JamesG161

SBO Weather and Forecasting Forum Jim & John
Feb 14, 2014
7,766
Hunter 430 Waveland, MS
Jun 14, 2010
2,341
Robertson & Caine 2017 Leopard 40 CT
@JamesG161 using non-ethanol fuel is a big help, but e10+ is inherently unstable and even with fuel stabilization specially made for ethanol it’s prone to phase separation and water accumulation. There’s lots of information online about this.
Edit: ps- in NY, CT, MA and RI (And many other states) you can’t buy non-ethanol fuel at the pump. Seems the corn lobbyists got to the legislations.
 
Jun 2, 2004
3,550
Hunter 23.5 Fort Walton Yacht Club, Florida
$10 worth of gas is not worth screwing up your car or your outboard over though I very seriously doubt if you added a half gallon in a fresh tank it would have any deleterious effect. Your city or county likely have a place to dispose of hazardous materials go there.

I throw mine in with the used oil when I change it but I surmise that if you are asking this question you are not one to change your own oil.
 
Apr 1, 2018
63
Hunter 41AC 1 Charleston
IMHO I would not put it in my car for all the above reasons but also if there is any water fresh or even worse saltwater in the tank it will be the most expensive few gallons of gas you ever bought.
 
Mar 20, 2015
3,236
C&C 30 Mk1 Winnipeg
There are cars without catalytic converters????
Yup. Both old "vintage" ones, and vehicles where owners have removed them (in places where they don't smog test). You can even remove diesel exhaust filters when they fail, and not replace them. If you know what you are doing, you can alter the firmware in the ECU so the it won't throw a code for a missing cat or diesel exhaust filter. Remove the inside of the pipe, and you save the high price of replacing it.

I'm not a fan of such things, but people do it. :badbad:

Best option to get rid of excess 2 cycle fuel is burn it in your lawnmower etc. or... get a 4 stroke, thereby reducing pollution and the hassle of 2 cycle fuel. We have 4 strokes and simply put the leftover fuel in our vehicles.
The only 2 stroke we have now, is a chainsaw. So we have minimal leftover fuel at risk of separation. We use ethanol free whenever possible of course.
 
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JamesG161

SBO Weather and Forecasting Forum Jim & John
Feb 14, 2014
7,766
Hunter 430 Waveland, MS
but e10+ is inherently unstable
I hope that is not true. Unstable means explosion potential, but by ambient chemical decomposition.

If you meant that is will not stay homogenized, perhaps.
My fuel tank is sealed and if topped off , has insignificant humidity to condense and separate. It is not diesel.
My 20:1 mix stays homogenized.

Never had a problem with Sta-bil use or my engine without dumping the fuel.
Jim...
 

Joe

.
Jun 1, 2004
8,191
Catalina 27 Mission Bay, San Diego
I've never had an issue with old gas in my 25 year old 10hp Tohatsu 2 stroke. 50:1 fuel/oil ratio. I don't have a lawnmower, either. My 4 stroke 3.5 hp tohatsu dinghy motor seems to run fine on the E10. Emission control laws were a blessing to California....... anyone who circumvents them for their personal pleasure is a low life. IMHO anyway. Engine manufacturers can make clean running motors if they want. It's their responsibility to society to do so....
 
Sep 24, 2018
3,395
Catalina 30 MKIII Chicago
If you know what you are doing, you can alter the firmware in the ECU so the it won't throw a code for a missing cat or diesel exhaust filter. Remove the inside of the pipe, and you save the high price of replacing it.
When I was young I did this. I bought a bypass kit that was essentially a resistor. It worked to trick the ECU. When I pulled in for emissions the kid working there heard how my car rumbled as I pulled up. He gave me a little smile. He knew what was up.

As for that two cycle I would be worried about clogging the injectors faster than normal