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2003 9.9 4 Stroke RPM Surging- Hunting above idle

K

Ky Howard

Contributing Member
Got a 2003 9.9 4 Stroke. Just overhauled the carburetor and set timing, etc. The motor is off the boat and has muffs on. It starts right up and idles fine but as soon as I try to increase RPM, it starts to surge or hunt, rev up, then down and will not run steady. Anyone got a fix or an idea what to check? Thanks in advance
 
Do you run the fuel out of the carburetor when done for the day ?----An empty carburetor stays clean.----Test run with another tank and hose.----Some carburetor cleaner added to fuel ( seafoam ) might help .----Or clean the carburetor.----Shocking what they charge at some shops for carburetor cleaning.
 
racerone said:
Do you run the fuel out of the carburetor when done for the day ?----An empty carburetor stays clean.----Test run with another tank and hose.----Some carburetor cleaner added to fuel ( seafoam ) might help .----Or clean the carburetor.----Shocking what they charge at some shops for carburetor cleaning.
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Thanks, but we "Just overhauled the carburetor and set timing, etc." which included cleaning the idle passages, main jet, setting float level, etc. When choked slightly to richen the mixture, it gets worse. It's almost like a rev limiter kicking in but the RPM is just above idle
 
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