Section 5 Fuel System and Governor Reassembly Procedure Reassemble the carburetor using the following steps. See Figure 5-6. As the flyweights move outward, they cause the regulating pin to move outward. The regulating pin contacts the tab on the cross shaft causing the shaft to rotate. 1. Assemble fuel inlet needle to the float tab. Install the float, float shaft and inlet needle to the carburetor upper body. Tighten the screw. Check float height using the procedure found previously in the "Adjustments" subsection. One end of the cross shaft protrudes through the crankcase.
The rotating action of the cross shaft is transmitted to the throttle lever of the carburetor through the external linkage. See Figure 5-7. 2. Install the slow jet so the stepped end will be toward the bottom of the carburetor. Make sure jet is fully seated. When the engine is at rest, and the throttle is in the “fast” position, the tension of the governor spring holds the throttle plate open. When the engine is operating, the governor gear assembly is rotating. The force applied by the regulating pin, against the cross shaft, tends to close the throttle plate.
The governor spring tension and the force applied by the regulating pin balance each other during operation, to maintain engine speed. 3. Install the low idle adjusting needle and spring. 4. Assemble the carburetor upper body and carburetor lower body using the four screws. Torque screws to 1.7 N·m (15 in. lb.) . 5 5. Install the carburetor on the engine following the procedures in Section 11 - "Reassembly". Governor When load is applied and the engine speed and governor gear speed decreases, the governor spring tension moves the governor arm to open the throttle plate wider. This allows more fuel into the engine, increasing engine speed.
As speed reaches the governed setting, the governor spring tension and the force applied by the regulating pin will again offset each other to hold a steady engine speed. General The engine is equipped with a centrifugal flyweight mechanical governor. It is designed to hold the engine speed constant under changing load conditions. The governor gear/flyweight mechanism is mounted inside the closure plate and is driven off the gear on the camshaft. The governor works as follow: Centrifugal force acting on the rotating governor gear assembly causes the flyweights to move outward as speed increases. Governor spring tension moves them inward as speed decreases. Figure 5-7. Governor Linkage. 5.11