1979 Johnson 140 hp kicking HARD

Troubledboater

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While driveing at any speed the engine kicks erratically, no pattern at all, so hard that it lifts out the water slightly and shakes the entire boat. What could be causeing this?
 

kenmyfam

Supreme Mariner
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Re: 1979 Johnson 140 hp kicking HARD

While driveing at any speed the engine kicks erratically, no pattern at all, so hard that it lifts out the water slightly and shakes the entire boat. What could be causeing this?

Well 2 things come to mind immediately.
Ignition problem
Fuel delivery problem.
Do a compression check first though to start the ball rolling and report your findings back.
Not much else can go wrong really with a 2 stroke to give those symptoms (that i can think of)
There are many experts out here that may well have other ideas though.
 

Troubledboater

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Re: 1979 Johnson 140 hp kicking HARD

But it doesn't turn off or anything. Just kicks and continues on. The engine doesn't do anything, like make a different noise or shut off, it almost feels like we are hitting something. And I know we're not.
 

CharlieB

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Apr 10, 2007
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Re: 1979 Johnson 140 hp kicking HARD

Is it only doing this at higher throttle in forward gear, never in reverse?

Try adjusting the shift cable two turns to put a little more pressure into forward gear and retest.

Did it improve or remain the same?
 

Troubledboater

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Re: 1979 Johnson 140 hp kicking HARD

It doesn't do it in reverse, but at any speed going foward it will kick, not just going faster. The only times it doesn't do it is when it's idleing or in reverse. Although, the faster I go, the more often it kicks.
 

iwombat

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Jul 12, 2006
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Re: 1979 Johnson 140 hp kicking HARD

That's your clutch dog coming off of mesh with the forward gear and slamming back in. It's either a misadjusted shift linkage or a worn clutch dog and forward gear. Even if it just stared out as a misadjustment, it's probably a worn dog by now.
 

kenmyfam

Supreme Mariner
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Aug 10, 2006
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Re: 1979 Johnson 140 hp kicking HARD

That's your clutch dog coming off of mesh with the forward gear and slamming back in. It's either a misadjusted shift linkage or a worn clutch dog and forward gear. Even if it just stared out as a misadjustment, it's probably a worn dog by now.

Makes sense to me. Especially now we have the "feels like hitting something" snippet of information provided.
 
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