At Start; At Idling; At High Speed Running With Overload; During Overload - Kubota B2410 Workshop Manual

1 ENGINE
11900F10180
B2410· B2710· B2910 WSM, 12271
• At Start
As no centrifugal force is applied to flyweight (7), low
tension of start spring (1) permits control rack to move to
the starting position, supplying the amount of fuel
required to start the engine.
• At Idling
Setting speed control lever (11) to the idling position
during engine rotation permits the low tension of
governor spring 2 (3), start spring (1) and idle limit spring
(12) to balance the centrifugal force of flyweight (7)
without activating high tension governor spring 1 (2). In
this way, the fuel injection rate can be controlled to
ensure stable idling.
• At High Speed Running with Overload
Governor spring 1 (2) and 2 (3) control the fuel
injection rate. To maintain the required engine speed,
fuel is supplied according to the speed control lever
setting and load by balancing the tension of governor
springs 1 and 2 with the centrifugal force of flyweight (7).
In addition, idle limit spring (12) provides stable
engine rotation.
• During Overload
At load increases, the engine speed decreases,
reducing the flyweight's centrifugal force. Governor
springs 1 (2) and 2 (3), therefore, pull fork levers 1 (4)
and 2 (5), increasing the fuel injection rate and
maintaining engine speed.
If engine speed decreases due to a further increase
in load, fork lever 2 (5) will come in contact with the fuel
limit bolt, stopping a further increase in the fuel injection
rate.
Torque spring (8) incorporated in fork lever 1 (4)
moves the lever in the direction of fuel injection rate
increase, thereby boosting torque and providing greater
engine output.
8
11900F10190
(1) Start Spring
(2) Governor Spring 1
(3) Governor Spring 2
(4) Fork Lever 1
(5) Fork Lever 2
(6) Fork Lever Shaft
(7) Flyweight
1-M18
(8) Torque Spring
(9) Governor Shaft
(10) Governor Sleeve
(11) Speed Control Lever
(12) Idle Limit Spring
(13) Fuel Limit Adjust Bolt
(14) Control Rack Pin
11900M 1 0200