need a prop expert

[rangerbassman]

I have a 17' bass boat I just bought used. It has a 1989 Johnson 120. This is my third bass boat in the last 15yrs and I never had to do much with the props, they all really got up and went fine. The reason I think I may need a prop is because it appears to have the original alluminum prop. When you have the motor fully down and nail it all the way down you hear the motor come up some and it seems to hesitate for a second or two before it takes off and planes out pretty fast. It almost feels like your pulling up a skiier for a second or two. It also has one of those fins on the lower unit, a first for me. At full throttle trimmed up it will run about 55mph, which is about right from my experence.. Also this thing really pulls to the right untill you get fully trimmed. I am a 25yr exp auto mechanic but not a boat mechanic. Any help? Dont be affraid to to get technical. I may be able to understand. If you have sume suggested spec's on a prop they will be welcome

 

[Dhadley]

Re: need a prop expert

What brand & model boat? Pad bottom we'll assume. We'll further assume it has a stepped transom. We'll also assume it's either mounted pretty low on the jackplate or it has no jackplate at all. I'd also bet we're no where near 6000 top rpm.

Assuming (again) all this is close, try it without the fin.

 

[rangerbassman]

Re: need a prop expert

It's a 1993 Cajun Pro 168, V-hull, The transom is straight and flat across 87". No jackplate. Runs nearly 6k flat out and trimmed. motor sits pretty low.

 

[Dhadley]

Re: need a prop expert

OK. Everything indicates that the motor is mounted too low. The hesitation part could be a motor issue. At 6K top end it should be a rocket out of the hole. I'd take the fin off and test again. If you still have a hesitation we may have to look closer at the motor. Especially if it's been sitting for a while.

Also see if you can get some numbers off of the prop. They should be right by the nut or on the side of the barrel.