Stalls when accelerating comming off idle

raystownfun

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May 27, 2009
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1979 Johnson 55hp- can sometimes accelerate with choking . Carbs were
rebuilt. Compression is 135/135 psi . Runs perfect at high speeds. Should I change power packs next. Can someone advise me?
 

ob

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Aug 16, 2002
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6,992
Re: Stalls when accelerating comming off idle

Sounds like either a restricted idle orifice on one or both carbs or a link/sych issue with respect to the position of the throttle link roller and cam.
 

jonesg

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Feb 22, 2008
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Re: Stalls when accelerating comming off idle

can sometimes accelerate with choking .

Carbs were rebuilt.

choking to accelerate is fuel delivery, don't discount the rebuilt carbs still being a problem but check everything from fuel tank to carbs first.
 

tashasdaddy

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Re: Stalls when accelerating comming off idle

if you have not, replace all fuel line with alcohol resistant lines, due to ethanol in the fuel. ethanol softens the inside of old fuel lines, handling the old lines, causes the interior to sluff off, and clogs the carb you just cleaned.
 

raystownfun

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Re: Stalls when accelerating comming off idle

Thanks. I also ordered a fuel pump rebuild kit. Does anyone know if there is a fuel filter somewhere on the motor that should be changed?
 

tashasdaddy

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Re: Stalls when accelerating comming off idle

only filter on that motor is screen in fuel pump.
 

raystownfun

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Re: Stalls when accelerating comming off idle

1979 johnson 55 hp
Rebuilt carbs.
Changed fuel pumps and fuel line from tank.
Changed one ignition coil and plugs again.
Replaced power pack.

Still bogs at low idle and just coming off idle.
Tolerable when i mess with the manual choke.

Mechanic says , " the could be internal problem, such as cylinder wall or piston out of round, therefore not enough vacuum to pull fuel at low end. Is this possible?
He also only cleaned low idle orifice and off idle orifice. Should they be replaced?
Thanks for your advise.
 

tashasdaddy

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Re: Stalls when accelerating comming off idle

linc n sinc. this is synchronization of the spark advance and the carbs,
 

raystownfun

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May 27, 2009
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Re: Stalls when accelerating comming off idle

Won't get to check link and sinc until next weekend.
Do you think this year engine is worth rebuilding?
Can anyone rebuild or do you need special tools?
Thank you again for your advice. I'll let you know how i make out.
 
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