I was given a Toro snowblower with not much information from the original owner except a vague "the wrong fuel was put in it so I was told it was ruined" explanation. The cap on the fuel tank says it's supposed to be a 50:1 mix, so my first though was they put regular gas in. But, the fuel that was in it visually looked like it was, indeed, a mix, but it would not start even after verifying it was getting fuel and spark.

I decided to take a little regular gas (un-mixed) and put it in directly in the carburetor to see if I could prime it and/or get any kind of life out of it. Fired right up and ran for a few seconds until it used up the fuel I dumped directly in. So I figured "Ok...maybe there is just something wrong THIS fuel in the tank". I disconnected the fuel line and drained it out and put in some fuel that I knew was 50:1. Still wouldn't start. Put a little regular gas in the carb again and it fired up. I then tried to put a little of the 50:1 directly in the carb also to see if it was a fuel delivery problem, but it would fire up with the mix.

What's the deal? It'll run on regular gas but not mix? I haven't found anything on the interwebs like this. Is this an indication of something?

  • 3
    DO NOT RUN A 2 stroke motor without 2 stroke oil in the fuel!! This will cause the piston to seize , a friend ruined one of my chainsaws (new cylinder and piston )
    – Ed Beal
    Commented Apr 8, 2020 at 16:13
  • 3
    These things are VERY sensitive to fuel sitting in the carb. My guess is that the first problem to solve it the carb float and/or jet. Get a carb rebuild kit or a new carb (on some models there are no serviceable parts in the carb and you just replace the entire thing). Then you may find there is nothing else wrong with it.
    – jwh20
    Commented Apr 8, 2020 at 16:21
  • Be sure all lines are clear and not kinked. I've had to replace 2-stroke carbs every once in a while on my garden tools. You might also replace the spark plug. Ed Beal: LOL, yeah, I get that. While I'm fairly generous loaning out tools, one thing I tell my friends is not to ask to borrow my chain saw! I'll say NO NO NO! Go rent one. Way too easy to damage a chain saw as well as liability issues. Commented Apr 8, 2020 at 16:53
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    By the way, does this engine have a place to put lubricating oil? I.E. an oil fill/drain site? Dipstick? Is there lube oil (10W30) in the sump? Because there might be an easy explanation for all this Commented Apr 8, 2020 at 16:55
  • Is that the correct cap? as Harper says...
    – Solar Mike
    Commented Apr 8, 2020 at 17:04

2 Answers 2


Here is what I discovered - the machine just appears to be really particular about having fresh gasoline. As I noted above, I put some fuel in that I knew was 50:1 that it still wouldn't run on, but I think it may have just been that it was a bit to old. It would run in my trimmer alright, but not the snowblower. I mixed up some completely fresh/new 50:1 and it would run on it.

However, the carb is definitely clogged. I pulled it off and couldn't get anything to drip through the jet. So, I'm either going to try to unclog it, or I'll just buy a new one


My guess is the engine still has both gunk and quite possibly a buildup of oil, and that's why it is currently "preferring" to run on pure gasoline. Sooner or later, however, the system will clean itself out and then is at risk of piston seizing.

If possible, disassemble and clean out the cylinder and the carb , or replace the carb as Ed Beal suggested.

If not, or you're brave, my recommendation would be to put maybe 20-30 cc of pure gas in the tank, run it dry. Then put in a little 50:1 . If it doesn't run, repeat with pure gas, 20 cc, and so on.

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