Never installing a water pump on a CD22 M 1965 Johnson 6 hp outboard I have some questions. The kit I ordered part # 763758 is quite different from the original. Everything fits but the impeller is about half the size of the old one. I assume that is ok seeing that everything fits. I have a question regarding a roll pin located on the drive shaft from the engine end. When I disassembled the lower unit from the power head I noticed this pin maybe 1/8" dia in the shaft close to the engine spline, it was damaged (bent). What is this pin used for? Do I need to replace it?

