89 johnson 225 starving for fuel at 4000 rpm

T

threeforme

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Hi, any suggestions on why my johnson outboard would run great at lower rpm under full load than it starts surging at 4000 rpm, i have to back off to 3000 rpm to fix the problem and than it runs fine and again at 4000 rpm surges! The motor is a 225 looper and the model number is

J225TXCED

Any help would be greatful....thanks
 
tashasdaddy

tashasdaddy

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Re: 89 johnson 225 starving for fuel at 4000 rpm

weak fuel pump, air leak in fuel line, clogging pickup in fuel tank, clogginf vent in fuel tank. clogging jets in carbs. is the fuel line bulb collasping, does it help if someone pumps the primer bulb?
 
T

threeforme

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Re: 89 johnson 225 starving for fuel at 4000 rpm

Fuel ball is not collasping, fuel line up to the engine is new, new vent, it does help when someone pumps the ball.....hummmmmmm
 
tashasdaddy

tashasdaddy

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Re: 89 johnson 225 starving for fuel at 4000 rpm

"it does help when someone pumps the ball" air leak, or fuel pump.
 
T

threeforme

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Messages
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Re: 89 johnson 225 starving for fuel at 4000 rpm

When i am testing the motor in water, out of the water, it seems to hold, but when it is put under load thats when i have the problem, would it be the fuel pump still? Where do you suggest that i look for an air leak?
 
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