No, you can't overtighten the impeller onto the shaft. It is threaded, and the butt end of the impeller mates against the shoulder of the shaft.
Were the bearings good, did it spin freely before?
Chances are that the blades are making contact with the wear ring if everything was good in the pump.
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"Riding an '89' is a Splash from the past
PJS Exhaust & Waterbox
Mariner Head - Decked at 185lbs compression
38mm Keihin
Ported & Flow Matched Stock Intake
R&D Reeds, Cages & Stuffers
Skat 15
R&D Toploader Scoopgrate
Ocean Pro rideplate
Pump drilled for dual cooling
500gph rule
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