Using mixed gas/oil in a non-mixed mower

My old lawnmower died and isn’t worth repairing. Old mower used gas mixed with 2-cycle oil. Have about 2 gallons of it in my garage. I bought a new mower yesterday and plan on using it for the first time tonight. It uses non-mixed gas. Can I use the rest of my mixed gas or would it mess up my new mower. I hate to throw the stuff out, but I don’t want to ruin my new mower.

I’ve used 2-cycle fuel (oil-gas mixture) in a 4-cycle engine without experiencing any problems. It just smokes a little more.

If you’re concerned, just dilute the oil-gas mixture with more gasoline. In other words, every time you fill up the mower with fresh gasoline, only fill the tank about three-quarters full, and then fill the rest with the oil-gas mixture.

From here:
Engines for lawn equipment usually come in two different flavors a 2-cycle and a 4-cycle. The 2-cycle engine is advantageous for smaller engines used in trimmers and chainsaws because of the power they can produce for their size. They are also used in regular lawnmowers. The 4-cycle engines are mainly used on lawnmowers and riding lawnmowers. One of the differences between the two is that in a 2-cycle the oil needs to be mixed with the gas and in a 4-cycle the oil is separate and is not burned with gas.

It is important to know what type of engine is on the lawn equipment because this is where the first “common sense” error occurs. If a 2-cycle engine does not get oil put in the gas it will seize up and be ruined. If a 4-cycle engine gets oil mixed in with the gas the carburetor may need to be overhauled and the spark plug replaced.

Which is what happened to me. My dad didn’t have the gas cans marked, and I didn’t look closely enough. :smack:

Yeah it shouldn’t hurt anything, go ahead and use it. a 50:1 or 100:1 gas to oil ratio will just make a 4-cycle engine smoke a bit more - it may foul the spark plug up a bit, but it would likely clear up. If you are concerned, just pour in a little more gas.

As percypercy implied, “Don’t do it!”, especially if it is new.
I shudder at the idea of the filthy spark plug, and the cakey shit in the ignition chamber. $2 worth of fuel to stuff a new $300-400 mower just doesn’t add up

I also think you would clog the fuel lines and jets, 2-stroke fuel is a lot thicker than 4-stroke.

Two gallons?! Just dump it and use new, clean gas.

As a hijack, I have never, ever, heard of or seen a **two-stroke **lawnmower. Only weedwackers and hedge trimmers etc.

Lawn-Boy makes 2-cycle engines.

To the OP. It hasn’t been since high school that I was able to tear apart and restore a lawnmower engine for fun. After you try to save the 4 bucks, can I have the motor?

Ugh. Forgot to link. Here ya go

You do risk fouling the plug and gunking up the carb. People get away with it because they do it (useing pre-mix) infrequently, but as practice, it would probably cause grief.

For the clearest mind and the least variables should you need to diagnose engine woes later, knowing you NEVER used anything but the recommended fuel will make you sleep better.
That being said, I probably use pre-mix gas/oil in my mower 3-4 times a season.

I’ve occasionaly put 2 stroke gas in my 4 stroke motor, with no ill effects at all.

If anything, it probably gave the motor increased upper cylinder lubrication.

I’d just dump the gas in question in my car’s tank, and refill my gas can with fresh un-oiled gas.

At the dilution that you’d have in a car’s tank, the 2-cycle oil isn’t going to do much of anything, and you haven’t wasted a gallon of gas either.

Penny wise, pound foolish … *Nuff said *

Where can you safely dump gasoline? I’ve been in this situation a few times, because my Stihl grass trimmer wants 50:1 gas:oil, and by Toro snowblower wants 32:1. I once dumped 1 1/2 gallons of mixed gas in my truck’s tank with about 18 gallons of straight, fresh gasoline. My truck ran very unhappily for about a week. Dumping it on the ground is obviously harmful. Even though it would be very diluted by the time it got to the sewage plant, dumping gasoline/oil down the toilet doesn’t seem like a good idea. :dubious:

Oops. When you put a colon in between gas and oil, I guess you get a :o .

You can’t really dump gasoline anywhere I have seen. Here’s what I do: put it in a metal container (like a coffee can) and let it sit somewhere safe and evaporate over a couple of days. Either that or just burn it in a safe environment.

Burned or evaporated gas is much less a problem than it getting into our drinking water.

I’m not a chemist, but I believe burning it would be much better on the environment than letting it evaporate.

Burning is lots better than evaporation.

Putting it in the car is actually the best option, as it will be used, burned and pollution controlled, and won’t screw anything up.
Enter all paranoid “OMG! DON"T PUT IT IN YOUR CAR!!” people now.*

Moan moan. Just dump it onto pavement of some kind and let it evaporate. I know, I know, the environment! But come on. Doing this like once in a year with a tiny amount of gasoline? Its not freaking plutonium… :smiley:

There’s a dirty joke in there somewhere…

Just a little factual note: If you dump gasoline on blacktop pavement, it will dissolve the asphalt, leaving a pothole. I’ll leave the environmental debates to Hail Ants. This is, after all, General Questions. :smiley: