921521-0620 Tohatsu SCREW

Illustration 1 g03453518
Typical example
(1) Crankcase breather
(2) Air Intake
(3) Electronic Control Module (ECM)
(4) Oil Level Gauge (Dipstick)
(5) Location for Oil Sample Valve
(6) Oil Filter
(7) Oil Filler
(8) Secondary Fuel Filters
Illustration 2 g03453526
Typical example
(9) Front Lifting Eye
(10) Water Pump
(11) Coolant Intake
(12) Tensioner
(13) Belt
(14) Coolant Outlet
Illustration 3 g03453529
Typical example
(15) Rear Lifting Eye
(16) Alternator
(17) Turbocharger
(18) Starter Solenoid
(19) Starting Motor
(20) Oil Drain Plug
(21) Flywheel
(22) Flywheel Housing
(23) Coolant Drain Plug
Illustration 4 g03467856
Typical examples
(24) Electric Priming Pump
(25) Primary Fuel Filter
(26) Mechanical Priming Pump
(27) Primary Fuel Filter
(28) Spin on Crankcase Breather Note: Item (28) is part of the filtered breather system.Note: Some components may be supplied loose.The C4.4 diesel engine is electronically controlled. The C4.4 engine uses an Electronic Control Module (ECM) that receives signals from the fuel injection pump and other sensors in order to control the fuel injectors. The pump supplies fuel to the fuel injectors.The four cylinders are arranged in-line. The cylinder head assembly has two inlet valves and two exhaust valves for each cylinder. The ports for the exhaust valves are on the right side of the cylinder head. The ports for the inlet valves are on the left side of the cylinder head. Each cylinder valve has a single valve spring. Each cylinder has a piston cooling jet that is installed in the cylinder block. The piston cooling jet sprays engine oil onto the inner surface of the piston in order to cool the piston. The pistons have a Quiescent combustion chamber in the top of the piston in order to achieve clean exhaust emissions. The piston pin is off-center in order to reduce the noise level.The pistons have two compression rings and an oil control ring. The groove for the top ring has a hard metal insert in order to reduce wear of the groove. The skirt has a coating of graphite in order to reduce wear when the engine is new. The correct piston height is important in order to ensure that the piston does not contact the cylinder head. The correct piston height also ensures the efficient combustion of fuel which is necessary in order to conform to requirements for emissions.A piston and a connecting rod are matched to each cylinder. The piston height is controlled by the distance between the center of the big end bearing and the center of the small end bearing of the connecting rod. Three different lengths of connecting rods are available in order to attain the correct piston height. The three different lengths of connecting rods are made by machining the blank small end bearing of each rod at three fixed distances vertically above the centerline of the big end bearing.The crankshaft has five main bearing journals. End play is controlled by thrust washers which are located on both sides of the number 3 main bearing.The timing case is made of aluminum. The timing gears are stamped with timing marks in order to ensure the correct assembly of the gears. When the number 1 piston is at the top center position on the compression stroke, the marked teeth on the idler gear will match with the marks that are on the fuel injection pump, the camshaft, and the gear on the crankshaft. There is no timing mark on the rear face of the timing case.The crankshaft gear turns the idler gear which then turns the following gears:
the camshaft gear
the fuel injection pumpThe camshaft and the fuel injection pump run at half the rpm of the crankshaft.The fuel injection pump that is installed on the left side of the engine is gear-driven from the timing case. The fuel transfer pump is driven by the fuel injection pump. The fuel transfer pump draws fuel from the primary fuel filter. The fuel transfer pump delivers the fuel to the secondary filter. The fuel then travels to the fuel injection pump.The fuel injection pump increases the fuel to a maximum pressure of 190 MPa (27557 psi). The fuel injection pump delivers the fuel to the fuel manifold (Rail). The fuel injection pump is not serviceable. The engine uses speed sensors and the Electronic Control Module to control the engine speed.The specifications for the C4.4 refer to the Specifications, "Engine Design".