I learned that an 2 stroke outboard needs a working thermostat to get the engine up temps for proper fuel ignition.
If it is stuck open, the plugs will foul in less than an hour and you get a nice oily goop out the exhaust port after you shut down and the motor cools.
Fouled plugs means the engine runs like *expletive deleted*it at trolling speeds and won't hit 5k rpm at wide open throttle.
New thermostat is on order.