115 Mercury Outboard Starting Rebuild - Change Crank and Install Pistons & Rods

This Mercury 115 HP, 4 cylinder, 2 stroke engine had developed a very audible knock that seems the worst at idle. The engine ran fine otherwise and had been running like this for a while, except that the noise is increasing.
When we pulled down the powerhead, we found a badly scored / scuffed piston. In looking for a shop to do the machine work to rebore, we found an engine that had a broken crankshaft at the flywheel with other parts in good condition. We have chosen to use the block, pistons and rods from the donor engine and are taking the good crank from the original engine. We will reuse all the other parts (fuel and electrical) from the original engine as it is a newer model. We are cleaning up the parts, installing the pistons and rods, and torquing up the rod bolts.

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