9.9 cuts out at wide open throttle

pontoon chief

Petty Officer 2nd Class
Joined
Aug 9, 2004
Messages
116
have a 94,9.9 evinrude that cuts out at wide open throttle.<br />When on the water it will run great for 15-20 seconds at wide open throttle than it dies out completely.<br />At times you can pull the choke out and it will catch and regain RPM's only to do the same thing again,but it will only catch sometimes,and it will only catch at the low RPM range just before it stalls.<br />Have rebuilt the carb,replaced the fuel pump,and even went as far as changing the CDI box thinking it might have something to do with the problem.So far nothing helped.<br />Any idea's?,as I have had this thing apart so many times I should have used zippers to put it together the last three times...
 

rickdb1boat

Supreme Mariner
Joined
Jan 23, 2002
Messages
11,195
Re: 9.9 cuts out at wide open throttle

Replace the primer bulb, as it may be the culprit. Try another fuel tank using fresh gas and oil mix, new fittings and fuel line to the tank and motor. If that does not help, I would re-clean the carb again, paying close attention to the float and float needle. Sounds like it starving for fuel. Reason being, if you hit the choke and it goes, you are basically injecting fuel into the cylinders that the carb is not, like it should be. Sounds like something in the carb is clogged up or out of adjustment(Float). The fuel bowl is just running out of fuel to provide to the carb and it dies. Make sure you blow out all the passages with compressed air and it might be a good idea to soak the carb overnight in carb cleaner and then blow it out real good. Then check the float to make sure it's "Floats" properly and adjust it to specs. Best I have for ya now...
 

pontoon chief

Petty Officer 2nd Class
Joined
Aug 9, 2004
Messages
116
Re: 9.9 cuts out at wide open throttle

Thanks,I have tried some of your suggestions but will rip the card apart one more time and see what I can find.
 

marinemech

Petty Officer 1st Class
Joined
Aug 12, 2004
Messages
250
Re: 9.9 cuts out at wide open throttle

check the main jet for debris also don't soak carb body in carb cleaner as it has been coated (sealed) at the factory and carb cleaner tends to destroy that stuff<br />also when the engine dies do you have to squeeze the primer to restart?<br />when you have carb apart make sure the gasket under the nozzle well is in good shape and float level and drop are at specified adjustments<br />iam asuming you are running 50:1 fuel mix and a good quality oil? (engine seizing?) what spark plugs are in it? should be champion QL82C i think<br />last check the ground where the black wire from the power pack connects i've seen a few that wern't tapped deep enough but it sounds like you have a fuel problem <br />just some thoughts and good luck
 

pontoon chief

Petty Officer 2nd Class
Joined
Aug 9, 2004
Messages
116
Re: 9.9 cuts out at wide open throttle

Thanks,I do not have to prime with the primer.Gaskets are new and in good shape,fuel is new and mixed at 50-1,new plugs put in also.<br />I have replaced the power pack and made sure the ground wire is tight.<br /><br />What would lowering the float ajustment do?Would that help the carb stay full of fuel and prevent the carb from running dry,if that is what is occuring?
 

marinemech

Petty Officer 1st Class
Joined
Aug 12, 2004
Messages
250
Re: 9.9 cuts out at wide open throttle

if you don't have to reprime carb is not empty<br />sometimes the core plug in the bottom of plastic nozzle is pressed in to far restricting fuel flow
 
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