Using 2-Cycle Gas Mix in 4-Cycle Engines


Old 09-02-08, 12:22 PM
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Using 2-Cycle Gas Mix in 4-Cycle Engines

I have a Stihl string trimmer. I mix Stihl 2-cycle oil with 89-octane gas in a 50:1 ratio for use in the trimmer. I mix one quart at a time. I usually have a pint left over at the end of each month, and the dealer said not to use the mix when it gets that old.

Rather than throw it out (where????) would there be any harm in pouring that pint into my car or truck on top of a full tank of gas? Both have FE engines and a full tank is around 15 gallons. That makes the 50:1 mixture 750:1, so I don't see any harm in it, but...
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Old 09-02-08, 12:55 PM
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I would not use that in your car
Old 09-02-08, 01:59 PM
Gunguy45's Avatar
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Well, I think the actual ratio would be more like 6000 to 1.
15 gal = 120 pints
Your ratio of mixed gas to clean gas is 120:1.
120:1 x 50:1 = 6000:1

At least I think

I doubt it would hurt anything. Probably more junk in the additives you can buy at the auto parts store.
Old 09-02-08, 03:36 PM
oldchevy4x4's Avatar
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I have always dumped old 2 stroke fuel into my vehicles, never had any problems.
Old 09-02-08, 03:44 PM
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Location: Michigan
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I have 5 --2cycle engine machines.
I add STA-BIL fuel stabilizer to the gas mixture & use it all
summer--no problems so far .
Old 09-02-08, 09:54 PM
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Go ahead. I wouldn't be afraid to go ahead and use it up in the trimmer though, if it is kept in a cool, dark, dry place. If the fuel has ethanol in it, it won't keep as long from what I understand. We don't have ethanol in our area yet. Just ues that little last pint up and mix a new batch every 5 weeks instead of 4....or pour it in the car if you want. You shouldn't have a problem either way.
Old 09-03-08, 07:35 AM
Join Date: Feb 2008
Location: Michigan
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I also have 2-2cycle snowblowers. I mix 4 gal. of gas w/ fuel
stabalizer-(50-1 mix. w/2 cycle oil )
If I have any left over in summer, I use in my 5 other machines.
No smoke & everything runs fine.
I think your dealer is a little over-cautious........................

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