40 horse johnson

brian3127

Chief Petty Officer
Joined
Jun 10, 2007
Messages
509
i have a 40 horse johnson and im looking at getting another prop for it the prop that is on it is chipped up. with 3guys in the boat i got the boat up to about 14mph (gps) speed at 5000 rpm. im looking for speed not power or a mixture of speed and some power to get it up on plane with 3 or more people in the boat the boat is a 15 tri hull fiberglass that weighs about 800 bls + motor.
 

steelespike

Supreme Mariner
Joined
Apr 26, 2002
Messages
19,069
Re: 40 horse johnson

Not an expert but::
We need the year of the motor and the size of the prop.number on prop -- X -- (diameter X pitch)
assuming the tach is accurate 14 at 5,000 would make the pitch really low (good load push)but not much speed.
In that application I think it may be a struggle to plane with 4 aboard unless they are fly weights.Do a compression check and be sure it is in good tune.Get the prop repaired and try a load again.Then we can tell if prop- selection will help.
 
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