F9.9 fourstroke carb problems?

[pontoon chief]

I am working on a 2003 9.9 4-stroke that is having carb issues.This motor is on a boat as a kicker motor to a 115 yamaha.I had to tear down the carbs in the 115 as they were clogged ,dirty,and in some areas coroded.The issues with the 115 solved I turned to the Yamaha kicker motor.Expecting the same conditions with this moror,I removed the carb and cleaned and blew out all passages etc and replaced the carb on the engine.This carb is equiped with the electric magnetic choke were when the key is pushed in the magnet engages the butterfly etc.
Prior to hooking everything back up,I installed a large 10 Micron spin on filter on the boat and hooked up both motors on the filter.
The 9.9 was hard starting but when placing my hand in front of the intake I did get the motor started,but it ran a little rough.I again removed the carb and took my time and again cleaned the carb.Again the the carb was installed back on the motor,this time with different results.The motor starts and idles fine,however it will not accept any throttle without popping,kicking or stalling.When I can get the RPM s raised past the idle,the motor will run great.However when I lower the RPMs the motor will again pop ,kick or most likely stall.
What the heck is going on.This motor is like brand new...\\Patrick

 

[steelespike]

Re: F9.9 fourstroke carb problems?

Have you tried a little choke to smooth it out.If it helps it would indicate a lean condition.Perhaps a poorly adjusted float.
It is possible if the fuel pump is suspect the filter might be restricting the fuel supply.
If the filter is between the pump and the tank it may be sucking air at the connector or connections.Sometimes
the disconnects won't leak gas but may leak air.

 

[JUSTINTIME]

Re: F9.9 fourstroke carb problems?

check fuel lines
also check that water separator, sounds like it is clogged again

 

[pontoon chief]

Re: F9.9 fourstroke carb problems?

check fuel lines
also check that water separator, sounds like it is clogged again

I changed both the fuel filter inside the cowling and the 10 micron filter and the condition persists.
I also changed the fuel supply and used a small 6 gallon remote tank with fresh gas eliminating the boat tank and fuel seperator,The problem persists.
With only a short hose and bulb setup, it leave little else to cause an air leak.
Any other causes come to mind?

 

[JUSTINTIME]

Re: F9.9 fourstroke carb problems?

did u clean the fuel pump?

 

[pontoon chief]

Re: F9.9 fourstroke carb problems?

No,I never gave that a thought.