1996 Force 120 Bent Prop+New Prop=Grinding/Vibration @ Low-Mid RPM

I have a 1996 Force 120 on a 1997 Procraft Bass 180DC. A few weeks ago I hit what I think was a rock while loading my boat up. The only initial damage seemed to be bent blades on my 19" aluminum prop. I cannot detect any propshaft wobble. I put a second-hand 22" Powertech SS prop on it and took it to the lake. At low to mid throttle there is a significant grinding or vibration that goes away at full throttle. I checked to make sure the new prop isn't touching the lower unit anywhere when I spin the prop in neutral (not running).

I am inquiring for opinions or thoughts on what might be the source of this grinding/vibration.

Thanks

Re: 1996 Force 120 Bent Prop+New Prop=Grinding/Vibration @ Low-Mid RPM

could have damaged some gear teeth inside lower unit,could be a bent propshaft.
javsam

Re: 1996 Force 120 Bent Prop+New Prop=Grinding/Vibration @ Low-Mid RPM

Could the vibration/grinding been caused by using the wrong thrust washer?

Re: 1996 Force 120 Bent Prop+New Prop=Grinding/Vibration @ Low-Mid RPM

You went from a 19 to a 22, that could be the cause. Pitch increase = RPM decrease so you lost about 600 rpm when you changed the prop. So if your top end was 5100 with the 19, your top end dropped to 4500 with the 22. Propeller induced vibration may be caused by inaccuracies in pitch, camber and section shape. Al props tend to be more forgiving with strikes than SS props so even though the possibllity of it damaging the shaft is still there, it would have been more likely if you were using the SS prop. Alot hinges on how fast you were going when you hit the object but the thrust washer should stay the same regardless of which prop you use as long as the prop is rated for that motor and the thrust washer has not worn below specs. Since AL props bend and flex, they are more forgiving and inaccuracies are less detected than with the SS prop. The SS prop needs to be correctly balanced by pitch, cup and blade size. You should have that prop scanned before you run with it again.