Prop question for a Johnson trolling motor

[chris0061]

Hello all, I just picked up a 1991 Johnson trolloing motor model number BFL2TK and was wondering if you can put a different prop on it like a minkota prop in stead of the omc prop? I looked my motor up and they have a 83/8 x4 and a 12 1/2 by 4 and that was omc. Would this be like proping a outboard. smaller for power and bigger for speed? My boat is a 1988 blue fin fish and ski so is somewhat heavy.

 

[Barnacle_Bill]

Re: Prop question for a Johnson trolling motor

Trolling motor props don't come with a large assortment like outboards. I suspect that the 2 you found have different size hubs and they are not interchangeable. There are a couple companies that make props for TMs. I tried a Kipawa prop on my Minnkota once but really couldn't tell much difference. Another one is Youngs who makes them out of aluminum but I haven't tried them.

 

[Silvertip]

Re: Prop question for a Johnson trolling motor

Trolling motors are very different and far more critical when it comes to props. Yes - in theory a bigger prop (diameter and pitch) would increase speed but only to a point where the motor cannot twist the prop any faster. The down side of this is that the motor would be drawing gobs of current in an attempt to turn the prop. A smaller prop would allow the motor to turn much more freely since it is taking less bite on the water and hence there is less current draw. Therefore motors have props based on thrust & current draw where current draw is optimized by the selected prop.

 

[chris0061]

Re: Prop question for a Johnson trolling motor

Kind of what I thought. I measured the one that is on it and it measured about 11.5 inches from tip of blade to other tip of blade. I gues I'll just have to get it out and try it. I wonder if the two different sizes of props on ********** were for the two different hubs they have. they show a standard and Hight thrust and mine is a high thrust by the picture of the skeg on both of them.