You don't need a special tool to loosen the con rod pin, remove your spark plug and feed some rope down the bore. I use old Telecom rope it works great, move the piston to a good spot and just use a hammer and punch to knock the pin around until loose. Same to tighten it back up. The rope stops your piston moving up the bore.
If you have no rope remove the head and stuff the bore full of rag and refit the head, easy.
Some water may have settled in your bottom bearing, there not hard to know the crank out of.
