What's the difference between fuel screws and pilot screws? Pilot screws I see mentioned in the "powerlaunch" book but not fuel screws? Help?
Mac
Member
Fuel jetting
I'm thinking you mean pilot jet and not pilot screw. The pilot jet is a fuel metering jet that is not adjustable. It is found inside the floatbowl. You can change jet sizes for more or less fuel but cannot adjust each individual jet. The fuel screw is located on the underside of the carbs and meters fuel by adjusting in small increments inward for leaner and out for more fuel. Three turns out is max.
I'm thinking you mean pilot jet and not pilot screw. The pilot jet is a fuel metering jet that is not adjustable. It is found inside the floatbowl. You can change jet sizes for more or less fuel but cannot adjust each individual jet. The fuel screw is located on the underside of the carbs and meters fuel by adjusting in small increments inward for leaner and out for more fuel. Three turns out is max.
It says pilot screws ( I know about the pilot jets), rechecked the book.
BigMac
New member
Pilot screw, fuel screw, air screw, idle air mixture screw - all the same. It's the only adjustable screw on the carb.norwegian said:
Pilot screw-controls the amount of fuel/air mixture in the idle(pilot) circuit
Air screw-controls the amount of air entering the mixture in the idle(pilot) circuit
Fuel screw-controls the amount of fuel entering the mixture in the idle(pilot) circuit
Don't know which/if any carbs use air or fuel screws but I know the Mikuni's have an Air JET, Pilot(fuel) JET and Pilot(idle mixture) screw that adjusts the amount of air/fuel mixture exiting the carb during idle. Turn the screw out, more mixture is allowed in (richens), turn it in, less mixture is allowed in (leans).
Air screw-controls the amount of air entering the mixture in the idle(pilot) circuit
Fuel screw-controls the amount of fuel entering the mixture in the idle(pilot) circuit
Don't know which/if any carbs use air or fuel screws but I know the Mikuni's have an Air JET, Pilot(fuel) JET and Pilot(idle mixture) screw that adjusts the amount of air/fuel mixture exiting the carb during idle. Turn the screw out, more mixture is allowed in (richens), turn it in, less mixture is allowed in (leans).