I'm wondering if anyone knows what the symptoms are that would indicate my 17 inch pitch 3 blade aluminum prop should be replaced on my 1990 90 hp Evinrude. I've had the motor for 5 years on my 16 foot Glastron V 162; prior to that, the motor was on a pontoon boat with, I assume, the same prop as I'm using now. My motor won't reach the 5500-5800 rpm range, so I'm wondering if the prop is worn out, and if it is, would this cause the motor to not reach the right wot rpm? The prop has no damage to it, other than age. Thanks.