2 lubricating system – Cub Cadet 8404 User Manual
Page 33

ENGINE SYSTEM
2-11
D615-W02 May-2003
615W220A
615W219A
2.2 LUBRICATING SYSTEM
A. FLOW OF LUBRICATING OIL
The lubricating oil is forced to each journal through the
oil passages of the cylinder block, cylinder head and
shafts. The oil, splashed by the crankshaft or thrown
off from the bearings, lubricates other engine parts
such as the push rods (11), tappets (12), camshaft
(14), and crankshaft (15).
B. OIL PUMP
The oil pump is a gear type. Whose rotors have tro-
choid lobes. The inner rotor (3) has 4 lobes and the
outer rotor (4) has 5 lobes, and they are eccentrically
engaged with each other. The inner rotor, which is driven
by the crankshaft through the gears, rotates the outer
rotor in the same direction, varying the space between
the lobes.
While the rotors rotate from (A) to (B), the space lead-
ing to the inlet port increases, which causes the oil to
flow through the inlet port.
When the rotors rotate to (C), the port to which the space
leads is changed from inlet to outlet.
At (D), the space decreases and oil is discharged
through the outlet port.
(1) Inlet
(3) Inner Rotor
(2) Outlet
(4) Outer Rotor
(1) Piston
(9) Rocker Arm Shaft
(2) Idle Gear
(10) Rocker Arm
(3) Oil Pump
(11) Push Rod
(4) Relief Valve
(12) Tappet
(5) Strainer
(13) Oil Pressure Switch
(6) Oil Filter Element
(14) Camshaft
(7) Bypass Valve
(15) Crankshaft
(8) Oil Pan