LUBRICATION SYSTEM - TM-9-2815-204-350019

an acceptable level during normal engine op-

28. FLYWHEEL HOUSING

eration. The oil cooler bypass valve opens at a

pressure differential of 15 psi when the oil

The cast aluminum flywheel housing is at-

cooler becomes clogged routing the oil to the

tached to the rear machined surface of the cyl-

inder and crankcase. The housing provides for

engine oil galleries.

the attachment of the rear engine mounts and

the transmission adapter assembly. The housing

f. Bearing Lubrication (fig. 18). The crank-

also covers the flywheel and provides a mount

shaft. connecting rod. and camshaft bushing-

for the starter assembly (fig. 3).

type bearings are lubricated from drilled pas-

29. LUBRICATION SYSTEM (Fig. 18)

sages in the cylinder and crankcase and through

the crankshaft journals and cheeks. Oil under

a. General. The engine has a full-pressure

pressure from the oil filters and oil cooler

enters the main oil gallery in the cylinder and

l u b r i c a t i n g . The pressure system in-

sures a continuous delivery of oil to all engine

crankcase. Oil flows from the oil gallery through

moving parts regardless of the angle at which

oil passages to the crankshaft main bearings

the vehicle may be inclined. The oil flow is

and camshaft bushing- type bearings. Oil lubri-

shown on figure 19.

cating the crankshaft main bearings flows around

the bearings to the drilled oil passages in the

b. Oil Pump. The oil pump is a dual unit

crankshaft journals and cheeks and to the con-

necting rod bearings. Excess oil leaving the

consisting of a scavenger and a pressure pump.

The oil pump is gear driven by the crankshaft

bearings flows back to the oil pan to be recir-

gear and an oil pump idler gear mounted on a

culated. The valve rocker arm bearings and

shaft extending from the No. 1 main bearing

other components of the valve train are lubri-

cap. The pressure oil pump picks up oil from

cated with oil fed through a passage leading

the oil reservoir at the front of the oil pan

from the rear camshaft bearing.

and delivers oil under pressure to the oil fil-

ters, oil cooler, and engine oil galleries. The

g. Piston Cooling Nozzle Assemblies. The

scavenger oil pump picks up oil from the rear

hypercycle principle depends upon proper piston

of the oil pan via a pickup tube and spills oil

operating temperature. Oil is conveyed through

back into the front reservoir. The scavenger

an individual oil gallery and directed to the in-

oil pump insures a continuous oil supply to the

side of the piston skirts by six cooling nozzle

pressure pump pickup at all times regardless

assemblies. This oil pressure is controlled by

of actual vehicle position.

an oil pressure control valve located in the oil

pressure regulator valve housing. Oil flow to

c. Oil Filters. The engine has two replace-

nozzles is controlled by a 15 psi minimum

able element-type oil filters (fig. 19). Both oil

pressure control valve.

filters are identical and interchangeable. The

dual unit oil filters are mounted on the oil

h. Fuel Injection Pump Lubrication. The

cooler and oil filter housing assembly at the

fuel injection pump is lubricated by the engine

left side of the engine. Pressurized lubricating

oil system. Oil is directed through oil galleries

oil is forced through the filters before entering

to an external flexible hose connected to the

the oil cooler and engine lubricating system.

fuel injection pump advance unit housing. Refer

The oil filter bypass valve is located below the

to TM 9-2910-223-35 for complete description

front oil filter. This valve routes oil directly

of fuel injection pump lubricating system. Oil

to the oil cooler if the oil filters become

leaving the injection pump returns to the engine

clogged. The bypass valve opens at a differential

oil pan through passages in the injection pump

pressure of 15 psi.

advance unit. The injection pump driven gear

(fig. 17) is lubricated by this return oil.

d. Oil Pan. The oil pan is stamped steel

with two magnetic drain plugs.

i. Turbosupercharger Lubrication. The tur-

e. Oil Cooler. The oil cooler is located at

bosupercharger is lubricated by engine oil from

the-rear of oil cooler and oil filter housing as-

the main oil gallery through an external line.

sembly. The coolant jacketed oil cooler per-

Oil from the turbosupercharger is returned to

forms two functions, to transfer heat to speed

the oil pan. Refer to TM 9-2990-201-35 for a

warm- up of lubricating oil during cold starts,

detailed description of turbosupercharger lu-

and to maintain lubricating oil temperature at

brication.