johnson 50 tuneing problems

[Benny1963]

bought johnson 50 cheap from a friend who had a good bit of work done .
carb kits .power pack .coils new ign parts under fly wheel
good comp 125 120 new fuel pump. carbs appear clean
motor acts like its loading up but the new plugs look clean
spark tested both cyls blue spark. doesnt want to idle
was whanting to know what else to look for have ordered manual
seems like it rung on one cyl but has bright spark . havent run with timing light yet.
thanks benny 1963

 

[WillyBWright]

Re: johnson 50 tuneing problems

Look for worn throttle shafts. They wear right where they pivot in the carb body. That screws up your ability to get any kind of decent idling characteristics because air gets in where it isn't supposed to. Both the shaft and body wear, but the shafts wear more and replacing them often makes a big difference. It's easy to see if they are worn without disassembly. Just watch how they move as you advance the throttle.

 

[Benny1963]

Re: johnson 50 tuneing problems

thanks willy b
but motor is running pretty bad
has oily mixture coming out exaust
seems to load up but plug are clean

 

[tashasdaddy]

Re: johnson 50 tuneing problems

check you decarb in the engine frequent asked questions, get the old carbon out.