I had a motor that was stuck (after sinking and sitting for several
years.
All I did was remove all the sparkplugs and spray oil in the cilinders
and after a couple of days I hooked up an air line to the sparkplug hole
and filled the cilender with air and it pushed the piston down. I did
this to alternating cilenders untill it rotated ok. Then all I did was
clean the carburator and use fresh gas and started it up.
This was a very easy process. and worked very well. The motor is still
running fine (it is a 1964 75hp Johnson)
I hope this helps you....
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