84 johnson 9.9 wot problems

[seahawk44]

I have an 84 johnson 9.9 sailmaster electric start that has a problem I have been chasing for 4 months and I need some help. The motor starts fine, idles fine and runs ok through about half throttle. At higher throttle it begins to run terribly and bogs down and quits at wide open throttle. I have checked resistance on all coils under flywheel, checked resistance from coils to their components (all ok). I replaced the power pack and swapped ignition coils with known good coils. Spark plugs are new. I have replaced both tank and fuel line connector to motor as well as bulb. I replaced fuel line to fuel pump, replaced fuel pump and overhauled carb. I have noticed some fuel spitting in carb which is a symtom of a reed problem. My question is will a reed problem cause running problems at mid to wot?

 

[bktheking]

Re: 84 johnson 9.9 wot problems

Welcome to Iboats seahawk! Typically no, bad reeds would make it hard to start and it wouldn't idle to save it's life. When you overhauled the carb, did you put a kit in it or just clean it?

 

[mikesea]

Re: 84 johnson 9.9 wot problems

It could,is the timerbase that provides timing rotate correctly ,its under the flywheel and should contact the roller on the carb,sometimes the roller and or the cam piece under the flywheel could wear out.If all that checks ojk and your spitting fuel outward from the carb,I would think you have an issue with the reeds,could be a screw from the butterfly came loose,or reed cracked

 

[seahawk44]

Re: 84 johnson 9.9 wot problems

Yes, I put a kit in the carb and the cam roller is set where it is supposed to be. when throttle is twisted to wot, the carb butterfly is opening completely up. Also, it will only idle at high idle. I think I will go ahead and put new reeds in it because of the spitting problem. But Im just not sure if it will correct the wot problem. Thanks for your replies.

 

[bktheking]

Re: 84 johnson 9.9 wot problems

Seems like you've done all the steps. Do the reeds then, not a big job at all, that will put your doubts to rest.

 

[kenmyfam]

Re: 84 johnson 9.9 wot problems

I'm still wondering about the cleanliness of the carb. Easy to miss something and sounds like a carb issue.
Just my 2 cents coming in at this stage.

 

[bktheking]

Re: 84 johnson 9.9 wot problems

I'm still wondering about the cleanliness of the carb. Easy to miss something and sounds like a carb issue.
Just my 2 cents coming in at this stage.

Ken, I always blame the carb, reeds are so rare to require replacement, but he says it's clean and kitted so what other options are there?

 

[kenmyfam]

Re: 84 johnson 9.9 wot problems

I think its worth a second look.