Your two-stroke engine won't start cleanly, runs rough, or smokes badly - and you've already checked the plug, the carburetor, and the fuel lines. Old or incorrectly mixed fuel is the culprit more often than anything else, and running the wrong ratio in a modern engine causes carbon buildup that takes a while to clean out. 40:1 pre-mixed fuel in a 1-gallon jug - the ratio specified by most manufacturers for two-stroke equipment in this engine displacement range. Pre-mixed means no guessing at the pump and no mixing errors that lean out or richen the mixture. The 1-gallon size is right for handheld equipment tanks and keeps fuel fresh longer than bulk jugs that sit half-empty through a season. Standard in lawn care crews and landscaping operations across northeast Nebraska and northwest Iow Stocked at Crofton Lumber and Akron Lumber.