Johnson 4 Carbureator Trouble?

[PoPeYe40]

Hi All: I've got a 1998 Johnson 4HP outboard, which I THINK, has some carburerator problems, and I'd like to see if anyone else has experienced the same thing. The motor starts and idles fine, however, when I start to apply some throttle, it tends to bog out. After I slowly get it up to about 3/4 throttle, it seems to run fine, however, if I drop the throttle too quickly, it bogs out again. Anyone else had the same problem, and if so, how did you correct it? I've replaced the plugs, so that eliminates ignition problems. I'm thinking maybe the main jet is clogged? Thanks in advance !

 

[Paul Moir]

Re: Johnson 4 Carbureator Trouble?

Welcome to Iboats, Popeye40!<br /><br />Bump (momentarily apply) the choke when it bogs and see if it picks up. The choke will enrich the fuel/air for a couple seconds. I think you're likely right but a little testing never hurt.<br />Replacing the plugs doesn't necessarily eliminate ignition problems, as cracked or otherwise damaged ignition coils are not uncommon. But if you can draw a 7/16" long spark with a good SNAP off each spark plug lead, it's most likely not a problem.

 

[PoPeYe40]

Re: Johnson 4 Carbureator Trouble?

Thanks for the welcome and advice, Paul! I'll check the spark, and try to give it a little choke to see if that helps.<br />I may just haul the motor down to the basement and rebuild the carburerator over the winter, while I have time, before the season starts; the rebuild kit is only 20 bucks.<br />Also, gotta get the bottom paint on when the weather gets a little warmer.... Thanks again!