I bought a used 2-cycle snowthrower that I'm using this season. I replaced the spark plug and it ran fine the first 2 times that I used it. I've used it a couple times since then and it runs very weak. It does not run at the full power that it did previously. Is this a gas/oil problem or could it be something else? Thanks!

 

don't think its your gas/oil ratio.... used? about how old... if it has a spark arrestor screen, make sure thats cleaned out and clear. exhaust port isn't clogged. as for your gas oil ratio, as long as your using fresh gas and the right oil at the right ratio, it shouldn't be that.