Alright, let's assume it's a common model and you're using the recommended type of oil for it.
Running a 40:1 weed eater on 50:1 oil may cause some issues with the engine. The 40:1 ratio is the amount of oil recommended for every gallon of gasoline. So if you're using 50:1, that means you're using more oil than what is recommended for the specific engine.
It's not recommended to use a higher oil ratio than what the manufacturer recommends, as it can lead to clogged air filters and oil build up in the engine which can cause a decrease in performance and could cause damage to the engine over time.
It's always best to stick with the recommended oil ratio for your specific equipment to ensure optimal performance and to prolong the life of your engine
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