Lubrication System - Jeep J-10 Series 1982 Technical & Service Manual

LUBRICATION SYSTEM
General
A gear-type positive displacement pump is mounted
at the underside of the block opposite the No. 4 main
bearing (fig. 1B-70). The pump brings oil up through the
pickup screen and inlet tube from the sump at the rear
of the oil pan. The oil is driven between the drive and
idler gears and the pump body, then is forced through
the outlet to the block. An oil gallery in the block routes
the oil to the inlet side of the full flow oil filter. After
passing through the filter element, the oil flows from
the center outlet of the filter head through an oil gallery
up to the main oil gallery, which extends the entire
length of the block.
Smaller galleries extend downward from the main oil
gallery to the upper insert of each main bearing. The
crankshaft is drilled internally to route oil from the
main bearing journals (except No. 4) to the connecting
rod journals. Each connecting rod bearing cap has a
small squirt hole. Oil flows through the squirt hole and
is dispersed as the crankshaft rotates. This dispersed oil
lubricates the camshaft lobes, distributor drive gear,
cylinder walls and piston pins.
The hydraulic valve tappets receive oil directly from
the main oil gallery. Oil is also routed to the camshaft
bearings through galleries. The front camshaft bearing
journal directs oil through the camshaft sprocket to the
timing chain. Rotation of the sprocket lubricates the
crankshaft sprocket and chain. Oil drains back to the oil
pan under the No. 1 main bearing cap.
The oil supply for the rocker arms and bridge and
pivot assemblies is provided by the hollow push rods
from the hydraulic valve tappets. Oil passes from each
tappet through the hollow push rod to a hole in the
corresponding rocker arm. Oil from the rocker arms
lubricates the valve train components, then flows down
through the push rod guide bores in the cylinder head
past the valve tappet area, and returns to the oil pan.
Oil Filter
A full flow oil filter, mounted on the lower right side
of the engine, is accessible through the hood opening. A
bypass valve incorporated in the filter mounting head on
the cylinder block provides a safety factor if the filter
should become inoperative as a result of dirt or sludge
accumulation (fig. 1B-71).
CAUTION: Use the short, 4.25-inch (107.95 mm) filter
on six-cylinder engine CJ vehicles. If the long, 5.44-inch
(138.18 mm) filter is used, it may contact the engine
support bracket or frame rail This can puncture the
filter and result in a loss of oil and possible engine
damage.
Tool J-22700 will facilitate removal of the oil filter.
Before installation, apply a thin film of oil to the re
placement filter gasket. Turn filter until gasket contacts
ENGINES 1B-47
the seat of the filter head. Tighten by hand only, follow
ing the instructions on the replacement filter. If the
instructions are not printed on the filter, tighten the
filter until the gasket contacts the seat and then tighten
an additional 3/4 turn.
Operate engine at fast idle and check for leaks.
Oil Pump
The positive-displacement gear-type oil pump is
driven by the distributor shaft, which is driven by a gear
connected to the camshaft. Lubrication oil is pumped
from the sump through an inlet tube and screen assem
bly that is pressed into the pump body (fig. 1B-71). The
pump incorporates a non-adjustable pressure release
valve to regulate maximum pressure. The spring tension
is calibrated for 75 psi (517 kPa) maximum pressure. In
the pressure release position, the valve permits oil to
bypass through a passage in the pump body to the inlet
side of the pump.
Removal
NOTE: Oil pump removal or replacement will not af
fect the distributor timing because thedistributor drive
gear remains in mesh with the camshaft gear.
(1) Drain engine oil.
(2) Remove oil pan. Refer to Oil Pan Removal for
procedure.
CAUTION: Do not disturb position ofoil inlet tube and
screen assembly in pump body. If tube is moved within
pump body, a replacement tube and screen assembly
must be installed to assure an airtight seal.
(3) Remove oil pump retaining screws, oil pump and
gasket.
Disassembly and Inspection
(1) Remove cover retaining screws, cover and gas
ket from pump body.
(2) Measure gear end clearance.
• Preferred Method:
(a) Place strip of Plastigage across full width of
each gear end (fig. 1B-72).
(b) Apply a bead of Loctite 515, or equivalent,
around perimeter of pump cover and install. Tighten
screws with 70 inch-pounds (8 N»m) torque.
(c) Remove pump cover and determine amount
of clearance by measuring width of compressed Plasti
gage with scale on Plastigage envelope. Correct clear
ance by this method is 0.002 to 0.006 inch (0.002 inch
preferred) [0.051 to 0.203 mm (0.051 mm preferred)].
• Alternate Method:
(a) Place straightedge across ends of gears and
pump body.
(b) Select feeler gauge that fits snugly but
freely between straightedge and pump body (fig. 1B-73).