The 2.3 hp has only forward unless you turn it around. It has a centrificul clutch
to give you neutral at idle speed.
There is a small screw on the carb bowl that allows you to easily drain the carb fuel out. There is a clear plastic tube thats leads the fuel outside of the engine housing. One can insert a WD-40 red tube sprayer into that tube and put some in the bowl for long term storage
. It really helps.
Fuel and perhaps some water in the bowl dry up and clog the miniscule metering jets. The Idle jet is not even cleanable without "modifying" the carb.
Look... this is an aircooled weed wacker motor
. It is not very powerful but it will push a 8-9 ft dink to the dock
at several knots and a few knotheads on board.
As for the "Use aviation fuel" comment... things get out of context fast. I suspect the tech was making an inocent comment based on the E10 or E15 conversation. I have heard others (No Tech) say similar things.
trend for "Green" cleaning
of small HP carbs is a sonic cleaner like they use for jewlery but bigger. Short of spending a few thousand on one of these I find if you dissasemble the bigger parts
and soak them in Lemon juce for a day or two it will often work.
$90 for a carb job? Thats about right...If you cannot do this simple task yourself you are at their mercy. Most Dealers charge $80 + an hour. (Ouch!)