Dodge dakota 2002 Service Manual page 1587

9 - 338 ENGINE 5.9L DIESEL
LUBRICATION (Continued)
the owners manual. The by-pass valve is calibrated
to open when it sees a pressure drop of more than
345 kPa (50 psi) across the oil filter.
The oil filter head then divides the oil between the
engine and the turbocharger. The turbocharger
receives filtered, cooled and pressurized oil through a
supply line from the filter head. The oil lubricates
the turbocharger and returns to the pan by way of a
drain tube connecting the bottom of the turbocharger
to a pressed in tube in the cylinder block.
Oil is then carried across the block to an angle
drilling which intersects the main oil rifle. The main
oil rifle runs the length of the block and delivers oil
to the crankshaft main journals and valve train. Oil
travels to the crankshaft through a series of transfer
drillings (one for each main bearing) and lubricates a
groove in the main bearing upper shell. From there
another drilling feeds the camshaft main journals.
The saddle jet piston cooling nozzles are also sup-
plied by the main bearing upper shell. J-jet piston
cooling nozzles are supplied by a separate oil rifle.
Plugs are used in place of saddle jets when J-jets are
used. J-jet hole locations are plugged when saddle jet
cooling nozzles are used. Crankshaft internal cross-
drillings supply oil to the connecting rod journals.
Another series of transfer drillings intersecting the
main oil rifle supply the valve train components. Oil
travels up the drilling, through a hole in the head
gasket, and through a drilling in the cylinder head
(one per cylinder), where it enters the rocker arm
pedestal and is divided between the intake and
exhaust rocker arm. Oil travels up and around the
rocker arm mounting bolt, and lubricates the rocker
shaft by cross drillings that intersect the mounting
bolt hole. Grooves at both ends of the rocker shaft
supply oil through the rocker arm where the oil trav-
els to the push rod and socket balls (Fig. 111) and
(Fig. 112).
DIAGNOSIS AND TESTING—ENGINE OIL
PRESSURE
(1) Remove the 1/8 npt plug from the top of the oil
filter housing.
(2) Install Oil Pressure Line and Gauge Tool
C-3292 with a suitable adapter.
(3) Start engine and warm to operating tempera-
ture.
(4) Record engine oil pressure and compare with
engine oil pressure chart.
CAUTION: If engine oil pressure is zero at idle, DO
NOT RUN THE ENGINE.
Engine Oil Pressure (MIN)
At Idle
At 2500 rpm
If minimum engine oil pressure is below these
ranges, (Refer to 9 - ENGINE - DIAGNOSIS AND
TESTING).
(5) Remove oil pressure gauge and install the 1/8
npt plug.
DR
68.9 kPa (10 psi)
206.9 kPa (30 psi)