carb problems on a 1990 70 johnson

jasonr83

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Sep 8, 2010
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I bought a 1990 70 Johnson and the Carb bowls were leaking so I got three OEM kits and rebuilt carbs. Put them back on and it run like a dream. The next morning I tried to start it and engine was turning over very slow and all three carbs are flooding and leaking out of throttle body. I'm very experience with engines and carbs. Im a master auto technician. I'm not sure what else I should check before I pull carbs again. I set floats at .725 measuring from Carb body to float. The primer does not leak when I press bulb. I'm having a hard time thinking that I messed up all three carbs unless I had the wrong specs for the levels. Anybody have any ideas on what to do next
 

fisherman912

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Oct 18, 2009
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Re: carb problems on a 1990 70 johnson

I would revisit the float settings and ensure that the needles were seating properly. It sounds like the needles not seating allowing to much fuel into the carb bowls.

With the carbs off fuel bowl removed, invert the carb body and check that the float is level and horizontal. Then turn them right side up and confirm the float drop is 1 1/8 to 1 5/8.

If all of this is good, and it is not equipped with a VRO system, check your fuel pump for dirty or clogged diaphram or check valve.
 

jasonr83

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Joined
Sep 8, 2010
Messages
11
Re: carb problems on a 1990 70 johnson

Thanks I will check that out. It is a vro engine
but it has been bypassed.
 
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