engin running very rough and not on all cylinders

[bruce728]

I have a 96 johnson 70. I did not run it for several months. I took it out and it did not run on all cylinders and was very rough. I changed the sparkplugs and replaced the gas/water seprator filter. It was filthy. Any thoughts on the problem? Can I clean the carbs or do they need to be rebuilt?
Also, when I hooked up the flush and started the engin, the prop was spinning as if it was in gear. Any thoughts on what would cause that?

 

[Daviet]

Re: engin running very rough and not on all cylinders

I would start with some quick checks first, compression and spark. If they are both good, it might be time to overhaul the carbs.

 

[bruce728]

Re: engin running very rough and not on all cylinders

BECAUSE OF THE AGE OF THE MOTOR AND THE CRAPPY GAS OUT THERE, i AM GOING TO ASSUME THE CARBS ARE BAD. Is this a matter of rebuilding them, or can I just clean them up?

 

[Daviet]

Re: engin running very rough and not on all cylinders

Rebuilding/cleaning is basicly the same thing. Remove the carbs and completely disassemble them, removing all orifices and core plugs, make sure all passages are cleaned with a cleaner and then followed by compressed air. Install new gaskets, seals and o-rings where required.

 

[bruce728]

Re: engin running very rough and not on all cylinders

OK, thanks. I think that is something I should get a pro to do. Even with the manuel, I could eaisly screw it up.