Water pump not working on Johnson 3.3 outboard 2 stroke.

Sounds like you need a new water pump impeller.
to access the impeller the bottom of the motor needs to be unbolted and the impeller is fitted to the shaft, it is keyed so it only goes on one way. ( impeller kits will come with new gaskets,grease.O-rings and a new key ). re-bolt the lower unit and test.

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