is this a Gas Problem?(40 hp Johnson)

CaptainRonn

Seaman Apprentice
Joined
Mar 28, 2010
Messages
31
I have a 60-62' 40 hp johnson and it runs fine when I keep the throttle at low power but when I try to give it some juice it sounds like it starts revving really fast and I lose all power until I pull the throtte back to low power and then I can feel it kick back in and start pushing the boat again I cant figure out what the problem is any help would be greatly appreciated. Could it be my spark plugs? or my rich lean settings?
 

wilde1j

Vice Admiral
Joined
Apr 15, 2002
Messages
5,964
Re: is this a Gas Problem?(40 hp Johnson)

Sounds like a spun prop hub. Prop shop can rehub or replace with new one.
 

F_R

Supreme Mariner
Joined
Jul 7, 2006
Messages
28,226
Re: is this a Gas Problem?(40 hp Johnson)

Unless it is electric shift. But I agree, it has all the symptoms of a spun prop hub.
 

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kenmyfam

Supreme Mariner
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Aug 10, 2006
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14,392
Re: is this a Gas Problem?(40 hp Johnson)

So can I just replace the prop?

Replace or re-hub. Check it first though. Mark the hub and the prop, go for a spin and then see if the marks still line up. If not the hub is slipping.
 

CaptainRonn

Seaman Apprentice
Joined
Mar 28, 2010
Messages
31
Re: is this a Gas Problem?(40 hp Johnson)

Any ideas on what it might be if the prop isn't the issue?
 

wilde1j

Vice Admiral
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Re: is this a Gas Problem?(40 hp Johnson)

Check the prop 1st and let us know what you find.
 

Nasbinator

Seaman
Joined
Apr 25, 2010
Messages
50
Re: is this a Gas Problem?(40 hp Johnson)

I just bought a new prop for this same motor and recieved it in the mail today. It was $100. My 40hp 1961 johnson was doing something similiar. A bolt came out of the shift rod connector. It would hold just enough to shift gears but when I accelerated it would pop back into neutral. It was just a thought.. It would be easy to check anyway.
 

CaptainRonn

Seaman Apprentice
Joined
Mar 28, 2010
Messages
31
Re: is this a Gas Problem?(40 hp Johnson)

Alright sounds good I just picked up a new prop anyway the one I already had was more or less in need of a change, so Im gonna go check it out and give you guys the 411 as soon as I get the opportunity:D
 
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