How to tell if oil is in gas?

Sep 24, 2018
2,549
O'Day 25 Chicago
We have a few gallons of gas that we can't remember if we added two stroke oil to. Is there an easy way to tell if we added gas to it? We're using amsoil 100:1 oil. The gas does not look blue but not sure if it would at that ratio
 

dLj

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Mar 23, 2017
3,372
Belliure 41 Sailing back to the Chesapeake
At that level it only matters if you are putting it in a two stroke that needs the oil. It won't harm a four stroke. The earlier two stroke mixtures with more oil could foul stuff, but not the 100:1 ratio...

dj
 
Sep 24, 2018
2,549
O'Day 25 Chicago
At that level it only matters if you are putting it in a two stroke that needs the oil. It won't harm a four stroke. The earlier two stroke mixtures with more oil could foul stuff, but not the 100:1 ratio...

dj
So in other words, just add some more at 100:1 to be on the safe side?
 

dLj

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Mar 23, 2017
3,372
Belliure 41 Sailing back to the Chesapeake
Oh, just realized you might be wanting to run it in a two stroke... In which case, if you think you'll use it all, I'd take those couple gallons, put it in a 5 gallon container and add the two stroke oil for 5 gallons. That way you'd be safe, if anything a little rich on oil which with that oil mix won't be bad. If you think that's worrysome, dump the two gallons into a four stroke gas engine and just start again. But you'd be fine with a slightly oil rich mixture, especially with that amsoil oil - that's good stuff! - up to you.

dj
 
Nov 6, 2006
9,884
Hunter 34 Mandeville Louisiana
Wouldn’t use it in a car that has a cat converter. Some of the additives will foul the converter. One dose won’t kill it but the damage is cumulative along with the normal stuff that is in gasoline that slowly kills the converter.
 

dLj

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Mar 23, 2017
3,372
Belliure 41 Sailing back to the Chesapeake
Wouldn’t use it in a car that has a cat converter. Some of the additives will foul the converter. One dose won’t kill it but the damage is cumulative along with the normal stuff that is in gasoline that slowly kills the converter.
Good point, I forget about modern cars, I've been running exclusively diesel cars for decades - totally forgot about the catalytic converters they now all run. Use a lawn mower...

dj
 
Jan 1, 2006
7,039
Slickcraft 26 Sailfish
It was axiomatic on the North Fork to put questionable gas in your car. Until a friend was delivering cabinets to CT and didn’t make it over the Throgs Neck Bridge. Then we all stopped doing that. Getting stuck on a NYC bridge is a bad day by any measure.
 
Jan 11, 2014
11,321
Sabre 362 113 Fair Haven, NY
The danger with 2 strokes is running with insufficient oil rather than too much oil. If you have added oil and now add more the worst that will happen is the plug may foul and it will be smokey.

If the gas is not ethanol free, then burn small amounts in your lawn mower until it is gone. Don't put old E10 gas in the outboard.
 

RussC

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Sep 11, 2015
1,578
Merit 22- Oregon lakes
Pour a pint or so in a glass jar. even at 100:1 color will be obvious if it has oil in it.
 
Sep 24, 2018
2,549
O'Day 25 Chicago
The gas was purchased at the dock. If it was from the gas station I wouldn't think twice about getting rid of it
 

dLj

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Mar 23, 2017
3,372
Belliure 41 Sailing back to the Chesapeake
When you bought your boat I though it was customary to get rid of the lawnmower as it just becomes a distraction from sailing.
I keep trying, but at this point the lawnmower is being used by my daughters boyfriend to keep the lawn I don't see often from becoming a hay field... Glad my daughter has good tastes in guys...

dj
 
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Tedd

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Jul 25, 2013
745
TES 246 Versus near Vancouver, BC
Wouldn’t use it in a car that has a cat converter. Some of the additives will foul the converter. One dose won’t kill it but the damage is cumulative along with the normal stuff that is in gasoline that slowly kills the converter.
I think that's overkill. Not only is this something OP only proposes to do once, but many older RX-7 owners routinely run two-stroke oil in their fuel, for years on end, without running into catalytic converter problems. What you say might be literally true, but it's very far from being a real-world-practical problem.