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Engine Running Problem


GARYWM's Avatar
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09-27-02, 12:16 PM   #1  
GARYWM
Onan Carb

I have a Onan B48G engine with a Nikki carb.and limited idle mixture screw and semi auto choke on a portable welder. It started running erraticly at high rpm and finally would idle only. Now when the throttle opens up it spit's gas out the carb. and stops running, but it will still idle. Plugs have black soot. I have rebuilt the carb. it was pretty gumed up from a dirty gas tank. I have cleaned the gas tank,cleaned fuel pump, and changed fuel filter. I also changed point's , condenser, and plugs.
I don't know if I missed a clogged port in the carb or due to the dirty gas a valve sticking at high speed. Thanks for the help.

 
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09-27-02, 06:50 PM   #2  
mikejmerritt
Hey GARYWM, check the intake valve clearance. If you have that much fuel moving in reverse something is pushing it and that almost has to be a tight or wobbly intake valve or as you mention a sticking valve.....Mike

 
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09-27-02, 07:39 PM   #3  
I agree....very good possibility of a valve lash problem.


"Who is John Galt?" - Ayn Rand (Atlas Shrugged)

God bless!

 
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09-30-02, 11:03 AM   #4  
GARYWM
IT turned out to be a stuck intake valve all gumed up. Thanks alot for the help! For the future, what is a gas additive to prevent this problem. The machine set's idle alot. Thanks again.

 
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09-30-02, 10:37 PM   #5  
There's not really any good fuel additive that i'm aware of. The best thing you can do is crank it up and let it run 5 or 10 minutes every 3 or 4 weeks max. That will prevent a whole list of possible problems.


"Who is John Galt?" - Ayn Rand (Atlas Shrugged)

God bless!

 
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