Spun Prop Hub - Shop says no

[ronnieb09]

2003 Johnson 25HP 2 Stroke Tiller

Last weekend, on the way back to the dock, I tried to get back on plane after coming through a long no wake zone. The engine RPM increased, but I lost forward thrust. I was still in forward gear and if I kept the engine RPM's below ~2500 I could keep moving, but any attempt to increase throttle and it seemed to rev without load.

My initial thoughts were that it was a spun hub, but the prop shop says no. They cannot turn it by hand, and he claims I might have had something around the prop and didn't notice it. I'm not so sure.

I plan to mark the prop/hub and go out again, but I'm not sure what else it could be?

 

[tashasdaddy]

Re: Spun Prop Hub - Shop says no

you are own right track.

 

[ezeke]

Re: Spun Prop Hub - Shop says no

How high above the bottom of the boat is your a/v plate (the horizontal plate just above the propeller)? Do you have any devices such as a transducer attached to the stern that are near the gearcase?

 

[ronnieb09]

Re: Spun Prop Hub - Shop says no

Anti-cavitation plate is flush with the keel. Transducer is mounted away from gearcase.

There was only one passenger in the boat, and the normal fishing gear. I've frequently ran two passengers with gear in rougher water without any problems in the past.

 

[F_R]

Re: Spun Prop Hub - Shop says no

Anti-cavitation plate is flush with the keel. Transducer is mounted away from gearcase.

There was only one passenger in the boat, and the normal fishing gear. I've frequently ran two passengers with gear in rougher water without any problems in the past.

Somebody was basing a diagnosis on (not) being able to turn it by hand??? Gimme a break. Was he the Impossible Hulk or something? He would have to be at least as strong as 25 horses to equal what the motor applies to the prop.

You are on the right track--test it by marking it. Then you will know.

 

[wicked]

Re: Spun Prop Hub - Shop says no

i also had the same problem(spun prop) it was an inexpensive fix too about $50.F R is right draw a straight line from prop to the bottom end and you will notice if it has moved!

 

[ronnieb09]

Re: Spun Prop Hub - Shop says no

I went ahead and bought a new Johnson 10.3x13 prop since the old blades were pretty worn. What a difference. I gained 3-4 mph on the top end, and moved up a bit higher in the rpm range to where I wanted to be. Turns out it was the prop. Thanks for the help.