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1B-38
ENGINES
(6) Remove cylinder head cover.
(7) Remove rocker arms and bridge and pivot
assemblies.
(8) Remove push rods.
NOTE: Retain push rods, bridge and pivot assemblies
and rocker arms in the same order as removed.
(9) Remove cylinder head and gasket.
(10) Remove hydraulic tappets.
(11) Remove timing case cover. Refer to Timing Case
Cover Removal for procedure.
(12) Remove timing chain and sprockets. Refer to
Timing Chain Removal for procedure.
(13) Remove front bumper or grille as required.
(14) Remove camshaft.
Camshaft Inspection
Inspect the camshaft bearing journals for an uneven
wear pattern or rough finish. If either condition exists,
inspect camshaft bearings. Inspect loaded (bottom) side
of bearing. This is the most probable location for bearing
failure. Replace camshaft and bearings as required. Re
fer to Camshaft Bearing Replacement for procedure.
Inspect the distributor drive gear for damage or exces
sive wear. Replace if necessary.
Inspect each cam lobe and the corresponding hydrau
lic valve tappet for wear. If the face of the tappet(s) is
worn concave, the corresponding camshaft lobe(s) will
also be worn. Replace both the camshaft and the
tappet(s).
If the camshaft appears to have been rubbing heavily
against the timing case cover, examine the oil pressure
relief holes in the rear cam journal. These holes relieve
oil pressure between the end of the camshaft and the
rear bearing plug.
Camshaft Installation
(1) Lubricate camshaft with Jeep Engine Oil Sup
plement (E.O.S), or equivalent.
(2) Install camshaft carefully to prevent damaging
camshaft bearings.
(3) Install timing chain, crankshaft sprocket and
camshaft sprocket with timing marks aligned. Refer to
Timing Chain Installation for procedure.
(4) Install camshaft sprocket retaining screw and
tighten.
(5) Install timing case cover with replacement oil
seal. Refer to Timing Case Cover Installation for
procedure.
(6) Install vibration damper.
(7) Install damper pulley, if removed.
(8) Install engine fan and hub assembly.
(9) Install drive belt(s) and tighten to specified ten
sion. Refer to Chapter 1C—Cooling Systems.
(10) Install fuel pump.
(11) Rotate crankshaft until No. 1 piston is at TDC
position on compression stroke.
(12) Install distributor and ignition wires. Install
distributor with rotor aligned with No. 1 terminal on cap
when distributor housing is fully seated on block.
(13) Install hydraulic tappets. Lubricate tappets and
all valve train components with Jeep Engine Oil Supple
ment (EOS), or equivalent.
NOTE: The EOS must remain in the enginefor at least
1,000 miles (1 609 km) but need not be drained until the
next scheduled oil change.
(14) Install cylinder head and gasket.
(15) Install push rods.
(16) Install rocker arms and bridge and pivot assem
blies. Alternately tighten capscrews for each bridge one
turn at a time to avoid damaging bridge.
(17) Install cylinder head cover. Refer to Cylinder
Head Cover for procedure.
(18) Install air conditioner condenser and receiver
assembly, if equipped.
CAUTION: Open both service valves before the air
conditioning system is operated.
(19) Install radiator, connect hoses and fill cooling
system with specified mixture. Refer to Chapter
1C—Cooling Systems.
(20) Install front bumper or grille, if removed.
(21) Check ignition timing and adjust as required.
Camshaft Bearing Replacement
Camshaft bearing replacement requires that the en
gine be removed from the vehicle. Remove timing case
cover, crankshaft, camshaft and rear bearing plug.
When installing bearings, use a screw-type tool that
provides constant force. Do not use a driver-type tool to
install bearings. Care must be taken to align oil holes in
bearings with oil gallery access holes in the cylinder
block. It is not necessary to line ream camshaft bearings
after installation.
HYDRAULIC VALVE TAPPETS
The hydraulic valve tappet consists of the tappet
body, plunger, plunger return spring, check valve as
sembly metering disc, plunger cap and lockring (fig. 1B-
56).
The tappet operates in a guide bore that intersects
with the main oil gallery.
Operation
The operating cycle of the hydraulic tappet begins
when the tappet is on the heel (base circle) of the cam
lobe (engine valve closed). A groove in the tappet body
aligns with the tappetoil gallery to admit pressurized oil
into the tappet (fig. 1B-57). A hole and groove arrange
ment admits the oil to the inside of the plunger. Oil is
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Troubleshooting
