Propeller spacer washer "knob"?

[Spankenstein]

Does anyone know for what purpose there is a knob or tab on one side of the Suzuki spacer washer (pic attached)? It seems as though it would throw off the balance, when spun at 5K RPM. Thanks in advance for any input.

Prop_Kit_Rear.jpg

[Harper]

Maybe if you told us which model it's from, someone might chime in. My DF150 has no such thing. But the prop probably doesn't spin that fast, since there's likely a gear ratio that reduces the prop speed well below engine RPMs. And It doesn't look like that is heavy enough at that close to the prop shaft to cause any imbalance. Just not enough moment that close to the shaft.

[Spankenstein]

Fair enough. I've never seen a spacer washer with a tab like that before. It came with my new 2020 DF90A, with a 3-blade Suzuki 14 X 22 prop. Thanks.

[Moonlighter]

Looks to be a part that is common to the 70 - 140 A series engines.

https://www.boats.net/product/suzuki...b1367fe7b61976

No doubt the engineers know what they are doing with that design. I wouldnt be stressing over it.

[Spankenstein]

Thanks for the reply Moonlighter. I'm not stressing it, just curious. If it's there just to hold a screwdriver up against, to knock it loose, ok. If it's there to position a certain way for balancing, I'd like to know that too. I like balanced propellers and automobile tires. Don't like vibration in either.

[gogittum]

Could well be for indexing, to keep something turning with it. I see that the center is splined.