'89 Johnson Propeller Issue(?)

[seaVT]

I had total motor failure on the Johnson 25 a while back, and rather put a newly rebuilt motor on my hard luck body, I did a resto on the Sea Nymph and afterwards starting feeling what I believe is a propeller issue. Those pics to follow.

 

[seaVT]

I wonder if someone could verify if this is the correct propeller ( 13-11)for this motor or whether its condition would cause me issues. The boat just doesn't "sound" right as it cuts a wake, kind of a warbley sound and a bit more engine movement than I think it should have. I know one of my motor mounts is starting to give up, so I may be experiencing a confluence of issues.
It's most noticeable at half throttle and below, top speed is not effected, I can top at about 24, and boat planes out fine. Any advice?

 

[racerone]

Is there a part # for the prop ?----And the diameter of prop is the first # ---The pitch is the second #-----So 13 X 11 seems wrong for your motor.

 

[seaVT]

Is there a part # for the prop ?----And the diameter of prop is the first # ---The pitch is the second #-----So 13 X 11 seems wrong for your motor.

There isn't as far as I can see, but I'll check again. The iboats store lets you choose from 8" to 15" props. Max RPM is listed at 5200-5800.
Anyone else know these old motors and what the stock diameter and pitch were?

 

[racerone]

???---The props for this motor are listed with 10" / 10.5" / 11" Diameters.-----Then the second number is the pitch ( angle of the blade ) likely from 8" to 15" ------Likely this motor left the factory with a 10" X 11" Prop.------But it is up to the owner / seller to select the correct prop for the type of boat and work load for the motor.

 

[seaVT]

???---The props for this motor are listed with 10" / 10.5" / 11" Diameters.-----Then the second number is the pitch ( angle of the blade ) likely from 8" to 15" ------Likely this motor left the factory with a 10" X 11" Prop.------But it is up to the owner / seller to select the correct prop for the type of boat and work load for the motor.

Excellent, thank you. So the "warbling" I hear is likely caused by cavitation from the increased diameter?
In selecting "load", other than choosing for the max RPM, how does one calculate that? Seeing the type of boat above and the load being generally me (215lbs) and my kids+ maybe another 240lbs, would you think the spec you referenced suitable (10x11)?
The first one on the IBoats search calls for 10-1/10" x 13 part# 2211-101-13.
Thanks again.

 

[iggyw1]

Just a thought here: Have you tried the motor t a different tilt position to see if the "warbling" decreases or goes away?

 

[seaVT]

Just a thought here: Have you tried the motor t a different tilt position to see if the "warbling" decreases or goes away?

A good thought, I did drop the prop closer to the transom as I was having a difficult time planing out when I was alone.
It is amazing what one can find when they look in the service manual. The 25 hp's came stock with a 10" x 13. Looks like I will get one on order unless someone has an "upgrade" suggestion.