[spldart]

Still hard to start with the air filter removed?
Did you confirm spark during cranking without pushing? (timing light)
Did you actually run compression test? (the gauge that screws into the spark plug hole)
Did you set carb float level and idle passage adjustment as per service manual?

Any four stroke motor only needs three things.
A spark. At just the right time.
Compression. A piston and two to five valves doing their job.
Proper air to fuel ratio. Carb delivering 14.5 to 1.

Something in that pyramid is messing things up.
Water in exhaust.
Wet air filter.
Weak to no spark when cranking but adequate for pushing.
Mixture off.
Engine let go, to little compression to start easy.

And blowing a fuse just because of heavy rain is NOT right. Something else is going on.
Clean water conducts enough to mess up sensitive electronics but not take out a 10 amp
fuse without there being something else major fuxed up.

I've had my gz through torrential downpours and 18 inches of flood waters. It has never
blown a fuse or died on me cuz of it.