1975 25hp johnson prop turns slow

Doesitfloat

Recruit
Joined
May 21, 2012
Messages
1
I went through a few threads and I might be close to the answer.
I have a 1975 Johnson 25EL75B
Prop turns and has thrust at idle, under load the prop is spinning but low thrust.
With the propellor off I can torque the bearing pin ( by hand) and move the bearing 3-5 degrees. Then it returns.
With the motor running and no prop, the unit shifts into both fwd and rev. While running at med throttle removing each of the spark plug wires resulted in lower RPM.
I think it is the Propellor and I hope it isn't something in the lower unit.
Any advice?
 

boobie

Supreme Mariner
Joined
Nov 5, 2009
Messages
20,826
Re: 1975 25hp johnson prop turns slow

Sounds like a spun prop hub.
 

samo_ott

Vice Admiral
Joined
Jun 18, 2006
Messages
5,125
Re: 1975 25hp johnson prop turns slow

Spun prop. Take it off and mark a line across the hub. Put it back on and run it. Then take it off and see if the line has moved.
 

Beek14

Petty Officer 1st Class
Joined
Jul 5, 2008
Messages
218
Re: 1975 25hp johnson prop turns slow

Spun prop. Take it off and mark a line across the hub. Put it back on and run it. Then take it off and see if the line has moved.

Agreed. BTW I wouldn't run the motor without the prop at any speeds above idle being you can over rev your engine which could result in bad news..
 
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