2GM20F engine issue

[Tipsynippertoo]

With the boat out of the water: If the prop' is serviced correctly the blades should rotate on their pivots just by their weight alone as the prop' is turned by hand at the hub.

 

[Ken13559]

My Kiwiprop rollers (3 pcs) are loose and spin freely. When underwater, I spin the shaft forward and reverse by hand and the Kiwiprop blades turns as it should in both direction without much effort. So I doubt my Kiwiprop is the problem

 

[Ken13559]

Finally I thicken the engine oil by adding STP Oil Treatment when engine is hot. After that, I could engage reverse without stalling the engine. I will plan for rebuild of engine. Thank you all.