On Tuesday, March 1, 2016 at 9:54:20 PM UTC-5, Arnie Goetchius wrote:
Oren wrote:
On Tue, 1 Mar 2016 19:47:36 -0500, Arnie Goetchius
wrote:

Can we assume that removing the spark plug did not change anything ie: engine is
still locked with the spark plug removed?

Can we assume the wrong plug size didn't crack the top of the piston?

I just wanted to see if he tested for Fuel vapor lock

Hydro lock can cause an engine to not be able to turn over, but
not vapor lock. Vapor lock is when the fuel in the fuel system
gets too hot and turns to vapor so it can't be properly pumped,
injected, etc. It won't prevent an engine from turning over,
only from starting/running. He also said that he pulled the engine
already and has it partially disassembled.

If it were me, I might consider calling up a small engine shop,
asking them what it would cost for a diagnosis, etc. Depends
on how comfortable one is doing that kind of repair, if you have
all the necessary tools, time, etc.