PIN AS 3864507 - Caterpillar

SHUTOFF CONTROL
1. Shutoff control. 2. Plug (pressure oil connection to water temperature shutoff). 3. Fuel rack shutoff reset cable assembly. 4. Pressure oil line to shutoff control. 5. Reset button. 6. Emergency manual shutoff button.The overspeed shutoff part of the control stops the engine mechanically in the event of engine overspeeding.Controls equipped with reversal protection are activated by low oil pressure only when the engine runs in reverse.The emergency manual shutoff button (6) works with the overspeed shutoff and provides the operator with an emergency shutoff control. DO NOT use the emergency manual shutoff button to shut down the engine in normal operation. This will cause more than normal wear on the overspeed shutoff parts.Reset button (5) is used to set the control after the engine has been stopped by the control because of low oil pressure. It is also used after the engine has been stopped because of high water temperature. It is not necessary to set the control after a normal engine stop.The shutoff control parts get lubrication from leakage past the oil pressure shutoff piston. Return oil goes through two drilled holes in the bottom of the housing.Shutoff Control Operation
Low Oil Pressure Shutoff and Water Temperature Shutoff
The oil pressure control will stop the engine when the lubrication oil pressure drops below 12 3 psi (85 20 kPa). It will also stop the engine when high water temperature opens a shutoff control valve which causes low oil pressure to the control.
SHUTOFF CONTROL (Cross Sectional Side View; Normal Operation)
1. Worm shaft. 2. Slide follower. 3. Slide follower shaft. 4. Cover. 5. Guide. 6. Piston. 7. Spring. 8. Release rod.Under normal engine operation, engine lubricating oil goes through line (4). (See illustration of Shutoff Control.) This oil goes to cover (4) and against control piston (6). (See illustration Shutoff Control, Cross Sectional Side View; Normal Operation.)One end of slide follower (2) is engaged with guide (5). The follower is free to pivot about slide follower shaft (3) in the housing and is activated by the movement of guide (5).Worm shaft (1) is turned by the shutoff drive which is turned by the fuel pump and governor drive shaft. Any time the engine is running the control is in operation.When the pressure of the engine oil is normal, piston (6) is held against guide (5) putting spring (7) in compression and keeps slide follower (2) out of contact