4-stroke 6 hp Tohatsu Outboard Issues
I recently bought a slightly used (told there were about 10 hours on it) tohatsu 4-stroke 6hp outboard motor to use with a mercury inflatable dinghy. I took it out for the first time this weekend and it ran great on its first trip.
When I took it out again the next day, it seemed to be working well again, but after about 30 minutes of use it seemed to suddenly make a more high-pitched noise and became what I describe as "jerky" or "jumpy." It almost seemed as if it might stall, but when i turned down the throttle a bit it still seemed run somewhat smoothly (still sounded a bit louder and high-pitched).
I was wondering if anyone might have an idea as to what caused this - I have a few thoughts/things to add:
-I believe the motor is due for an oil change. The person I bought it from said it could use one in the near future.
-I used the gas that was sitting in the fuel tank when I bought it. I'm not sure how old it was and in retrospect this was probably a bad idea. Could this be the issue?