Logo
FULL SITE MENU

20hp 1976 johnson rough running

W

Wayne Styles

Guest
Hi
My 20hp johnson is running

Hi
My 20hp johnson is running rough. I recently changed one of the two coils having confirmed no spark in the one plug. It ran well for about two hours with simular results (seems like is running on one cylinder) eventually showing up. I'm getting lots of spark off both coils now and the new spark plugs are somewhat dry which I think is OK concidering the way it is running. That leaves fuel & carburator. A new carb kit was installed 3 years ago. How do I check fuel pressure? Does the carb suck in fuel as well as the fuel pump?

Lost
 
"Most carbs that I'm famil

"Most carbs that I'm familar with have a float in a float bowl. Fuel pump sends gas to carb, when the gas fills the bowl the float rises and closes(plugs) a hole(seat), then when the gas goes to be burned it empties the float bowl and the float falls to let fuel into the carb again. I dont beleive carbs "pump" fuel. You could test fuel pump, I believe by running a by pass hose into a gas can, run the motor. If gas comes out it's pumping. Maybe someone can jump in here that knows a better way. I just assume if there's gas in the float bowl when drain is removed that the pump is working, and there's no other problems with clogs, air leaks, and such..."
 
Back
Top