
COOLING SYSTEM TESTER METHOD
WARNING: WITH COOLING SYSTEM TESTER IN
PLACE, PRESSURE WILL BUILD UP FAST. EXCES-
SIVE PRESSURE BUILT UP, BY CONTINUOUS
ENGINE OPERATION, MUST BE RELEASED TO A
SAFE PRESSURE POINT. NEVER PERMIT PRES-
SURE TO EXCEED 138 kPa (20 psi).
Install Cooling System Tester 7700 or equivalent to
pressure cap neck. Start the engine and observe the
tester's pressure gauge. If gauge pulsates with every
power stroke of a cylinder a combustion pressure
leak is evident.
CHEMICAL TEST METHOD
Combustion leaks into the cooling system can also
be checked by using Bloc-Chek Kit C-3685-A or
equivalent. Perform test following the procedures
supplied with the tool kit.
REMOVAL
(1) Disconnect the battery negative cable.
(2) Drain cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(3) Remove the air cleaner resonator and duct
work.
(4) Remove the intake manifold-to-generator
bracket support rod. Remove the generator.
(5) Remove closed crankcase ventilation system.
(6) Disconnect the evaporation control system.
(7) Perform the Fuel System Pressure Release pro-
cedure (Refer to 14 - FUEL SYSTEM/FUEL DELIV-
ERY - STANDARD PROCEDURE). Disconnect the
fuel supply line (Refer to 14 - FUEL SYSTEM/FUEL
DELIVERY/QUICK CONNECT FITTING - STAN-
DARD PROCEDURE).
(8) Disconnect accelerator linkage and if so
equipped, the speed control and transmission kick-
down cables.
(9) Remove distributor cap and wires.
(10) Disconnect the coil wires.
(11) Disconnect heat indicator sending unit wire.
(12) Disconnect heater hoses and bypass hose.
(13) Remove cylinder head covers and gaskets
(Refer to 9 - ENGINE/CYLINDER HEAD/CYLIN-
DER HEAD COVER(S) - REMOVAL).
(14) Remove intake manifold (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
REMOVAL) and throttle body as an assembly. Dis-
card the flange side gaskets and the front and rear
cross-over gaskets.
(15) Remove exhaust manifolds (Refer to 9 -
ENGINE/MANIFOLDS/EXHAUST MANIFOLD -
REMOVAL).
(16) Remove rocker arm assemblies and push rods.
Identify to ensure installation in original locations.(17) Remove the head bolts from each cylinder
head and remove cylinder heads. Discard the cylin-
der head gasket.
(18) Remove spark plugs.
CLEANING
Clean all surfaces of cylinder block and cylinder
heads.
Clean cylinder block front and rear gasket surfaces
using a suitable solvent.
INSPECTION
Inspect all surfaces with a straightedge if there is
any reason to suspect leakage. If out-of-flatness
exceeds 0.00075mm (0.0001in.) times the span length
in any direction, either replace head or lightly
machine the head surface.
FOR EXAMPLE:ÐA 305 mm (12 in.) span is
0.102 mm (0.004 in.) out-of-flat. The allowable out-of-
flat is 305 x 0.00075 (12 x 0.00075) equals 0.23 mm
(0.009 in.). This amount of out-of-flat is acceptable.
The cylinder head surface finish should be
1.78-3.00 microns (70-125 microinches).
Inspect push rods. Replace worn or bent rods.
INSTALLATION
(1) Clean all surfaces of cylinder block and cylin-
der heads.
(2) Clean cylinder block front and rear gasket sur-
faces using a suitable solvent.
(3) Position new cylinder head gaskets onto the
cylinder block.
(4) Position cylinder heads onto head gaskets and
cylinder block.
(5) Starting at top center, tighten all cylinder head
bolts, in sequence (Fig. 6).
Fig. 6 Cylinder Head Bolt Tightening Sequence
9 - 80 ENGINE 5.2LBR/BE
CYLINDER HEAD (Continued)

(1) When refacing valve seats, it is important that
the correct size valve guide pilot be used for reseat-
ing stones. A true and complete surface must be
obtained.
(2) Measure the concentricity of valve seat using a
dial indicator. Total runout should not exceed 0.051
mm (0.002 in.) total indicator reading.
(3) Inspect the valve seat with Prussian blue, to
determine where the valve contacts the seat. To do
this, coat valve seat LIGHTLY with Prussian blue
then set valve in place. Rotate the valve with light
pressure. If the blue is transferred to the center of
valve face, contact is satisfactory. If the blue is trans-
ferred to the top edge of valve face, lower valve seat
with a 15É stone. If the blue is transferred to bottom
edge of valve face raise valve seat with a 60É stone.
(4) When seat is properly positioned the width of
intake seats should be 1.016-1.524 mm (0.040-0.060
in.). The width of the exhaust seats should be 1.524-
2.032 mm (0.060-0.080 in.).
VALVE SPRINGS
Whenever valves have been removed for inspection,
reconditioning or replacement, valve springs should
be tested. As an example the compression length of
the spring to be tested is 1-5/16 in.. Turn table of
Universal Valve Spring Tester Tool until surface is in
line with the 1-5/16 in. mark on the threaded stud.
Be sure the zero mark is to the front (Fig. 13). Place
spring over stud on the table and lift compressing
lever to set tone device. Pull on torque wrench until
ping is heard. Take reading on torque wrench at this
instant. Multiply this reading by 2. This will give the
spring load at test length. Fractional measurements
are indicated on the table for finer adjustments.
Refer to specifications to obtain specified height and
allowable tensions. Discard the springs that do not
meet specifications.
REMOVAL
(1) Remove the cylinder head (Refer to 9 -
ENGINE/CYLINDER HEAD - REMOVAL).
(2) Compress valve springs using Valve Spring
Compressor Tool MD- 998772A and adapter 6716A.
(3) Remove valve retaining locks, valve spring
retainers, valve stem seals and valve springs.
(4) Before removing valves, remove any burrs from
valve stem lock grooves to prevent damage to the
valve guides. Identify valves to ensure installation in
original location.
CLEANING
Clean valves thoroughly. Discard burned, warped,
or cracked valves.
Remove carbon and varnish deposits from inside of
valve guides with a reliable guide cleaner.
INSPECTION
Measure valve stems for wear. If wear exceeds
0.051 mm (0.002 in.), replace the valve.
Measure valve stem guide clearance as follows:
(1) Install Valve Guide Sleeve Tool C-3973 over
valve stem and install valve (Fig. 14). The special
sleeve places the valve at the correct height for
checking with a dial indicator.
(2) Attach dial indicator Tool C-3339 to cylinder
head and set it at right angles to valve stem being
measured (Fig. 15).
(3) Move valve to and from the indicator. The total
dial indicator reading should not exceed 0.432 mm
(0.017 in.). Ream the guides for valves with oversize
stems if dial indicator reading is excessive or if the
stems are scuffed or scored.
Fig. 13 Testing Valve Spring for Compressed
Length
1 - TORQUE WRENCH
2 - VALVE SPRING TESTER
Fig. 14 Positioning Valve with Tool C-3973
1 - VALVE
2 - SPACER TOOL
9 - 84 ENGINE 5.2LBR/BE
INTAKE/EXHAUST VALVES & SEATS (Continued)

CAUTION: Support crankshaft before removing
main bearing caps. failure to do so will allow the
crankshaft to fall damaging the crankshaft.
(7) Using a suitable jack, support the crankshaft.
(8) Identify main bearing caps before removal.
Remove main bearing caps and bearings one at a
time.
(9) Lower the crankshaft out of the block.
(10) Remove and discard the crankshaft rear oil
seals.
(11) Remove and discard the front crankshaft oil
seal.
INSTALLATION
(1) Clean Gasket Maker residue and sealant from
the cylinder block and rear cap mating surface. Do
this before applying the MopartGasket Maker and
the installation of rear cap.
(2) Lightly oil the new upper seal lips with engine
oil.
(3) Install the new upper rear bearing oil seal with
the white paint facing towards the rear of the engine.
(4) Position the crankshaft into the cylinder block.
(5) Lightly oil the new lower seal lips with engine
oil.
(6) Install the new lower rear bearing oil seal into
the bearing cap with the white paint facing towards
the rear of the engine.
(7) Apply 5 mm (0.20 in) drop of MopartGasket
Maker, or equivalent, on each side of the rear main
bearing cap (Fig. 23). DO NOT over apply sealant or
allow the sealant to contact the rubber seal. Assem-
ble bearing cap to cylinder block immediately after
sealant application.
(8) To align the bearing cap, use cap slot, align-
ment dowel and cap bolts. DO NOT remove excessmaterial after assembly. DO NOT strike rear cap
more than 2 times for proper engagement.
(9) Clean and oil all cap bolts. Install all main
bearing caps. Install all cap bolts and alternately
tighten to 115 N´m (85 ft. lbs.) torque.
(10) Install oil pump (Refer to 9 - ENGINE/LU-
BRICATION/OIL PUMP - INSTALLATION).
(11) Install the timing chain cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION).
(12) Install the vibration damper (Refer to 9 -
ENGINE/ENGINE BLOCK/VIBRATION DAMPER -
INSTALLATION).
(13) Position the connecting rods onto the crank-
shaft and install the rod bearing caps. Tighten the
nuts to 61 N´m (45 ft. lbs.).
(14) Apply MopartSilicone Rubber Adhesive Seal-
ant, or equivalent, at bearing cap to block joint to
provide cap to block and oil pan sealing (Fig. 24).
Apply enough sealant until a small amount is
squeezed out. Withdraw nozzle and wipe excess seal-
ant off the oil pan seal groove.
(15) Install new front crankshaft oil seal (Refer to
9 - ENGINE/ENGINE BLOCK/CRANKSHAFT OIL
SEAL - FRONT - INSTALLATION).
(16) Immediately install the oil pan (Refer to 9 -
ENGINE/LUBRICATION/OIL PAN - INSTALLA-
TION).
(17) If the transmission was removed, install the
transmission.
Fig. 23 Sealant Application to Bearing Cap
1 - .25 DROP OF LOCTITE 515 ON BOTH SIDES OF REAR MAIN
CAP
Fig. 24 Apply Sealant to Bearing Cap to Block Joint
1 - MOPARTGEN II SILICONE RUBBER ADHESIVE SEALANT
NOZZLE TIP
2 - SEALANT APPLIED
3 - CYLINDER BLOCK
4 - REAR MAIN BEARING CAP
BR/BEENGINE 5.2L 9 - 89
CRANKSHAFT (Continued)

CRANKSHAFT MAIN
BEARINGS
DESCRIPTION
Main bearings (Fig. 25) are located in the cylinder
block. One half of the main bearing is located in the
crankshaft main bore the other half of the matching
bearing is located in the main bearing cap. there are
five main bearings. Number three main bearing is
flanged, this flange controls crankshaft thrust.
OPERATION
The main bearings encircle the crankshaft main
bearing journals, this aligns the crankshaft to the
centerline of the engine and allows the crankshaft to
turn without wobbling or shaking therefore eliminat-
ing vibration. The main bearings are available in
standard and undersizes.
STANDARD PROCEDUREÐCRANKSHAFT MAIN
BEARING FITTING
Bearing caps are not interchangeable and should
be marked at removal to ensure correct assembly.
Upper and lower bearing halves are NOT inter-
changeable. Lower main bearing halves of No.2 and 4
are interchangeable.
Upper and lower No.3 bearing halves are flanged
to carry the crankshaft thrust loads. They are NOT
interchangeable with any other bearing halves in the
engine (Fig. 26). Bearing shells are available in stan-
dard and the following undersizes: Never install an
undersize bearing that will reduce clearance below
specifications.
Main Bearing Undersize Availability List
²0.25 mm (0.001 inch)
²0.051 mm (0.002 inch)
²0.076 mm (0.003 inch)
²0.254 mm (0.010 inch)
²0.305 mm (0.012 inch)
REMOVAL
(1) Remove the oil pan (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - REMOVAL).
(2) Remove the oil pump from the rear main bear-
ing cap (Refer to 9 - ENGINE/LUBRICATION/OIL
PUMP - REMOVAL).
(3) Identify bearing caps before removal. Remove
bearing caps one at a time.
(4) Remove upper half of bearing by inserting
Crankshaft Main Bearing Remover/Installer Tool
C-3059 into the oil hole of crankshaft (Fig. 27).
(5) Slowly rotate crankshaft clockwise, forcing out
upper half of bearing shell.
INSTALLATION
Only one main bearing should be selectively fitted
while all other main bearing caps are properly tight-
ened. All bearing capbolts removed during service
procedures are to be cleaned and oiled before instal-
lation.
When installing a new upper bearing shell, slightly
chamfer the sharp edges from the plain side.
(1) Start bearing in place, and insert Crankshaft
Main Bearing Remover/Installer Tool C-3059 into oil
hole of crankshaft (Fig. 27).
(2) Slowly rotate crankshaft counterclockwise slid-
ing the bearing into position. Remove Tool C-3059.
(3) Install the bearing caps. Clean and oil the
bolts. Tighten the capbolts to 115 N´m (85 ft. lbs.)
torque.
(4) Install the oil pump (Refer to 9 - ENGINE/LU-
BRICATION/OIL PUMP - INSTALLATION).
Fig. 25 Main Bearing Orientation
Fig. 26 Main Bearing
9 - 90 ENGINE 5.2LBR/BE

OPERATION
The crankshaft seals prevent oil from leaking from
around the crankshaft, either from the rear of the
engine or from the engine front cover.
REMOVAL
The service seal is a two piece, Viton seal. The
upper seal half can be installed with crankshaft
removed from engine or with crankshaft installed.
When a new upper seal is installed, install a new
lower seal. The lower seal half can be installed only
with the rear main bearing cap removed.
UPPER SEAL ÐCRANKSHAFT REMOVED
(1) Remove the crankshaft (Refer to 9 - ENGINE/
ENGINE BLOCK/CRANKSHAFT - REMOVAL). Dis-
card the old upper seal.
UPPER SEALÐCRANKSHAFT INSTALLED
(1) Remove the oil pan (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - REMOVAL).
(2) Remove the oil pump (Refer to 9 - ENGINE/
LUBRICATION/OIL PUMP - REMOVAL).
(3) Remove the rear main bearing cap. Remove
and discard the old lower oil seal.
(4) Carefully remove and discard the old upper oil
seal.
LOWER SEAL
(1) Remove the oil pan (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - REMOVAL).
(2) Remove the oil pump (Refer to 9 - ENGINE/
LUBRICATION/OIL PUMP - REMOVAL).
(3) Remove the rear main bearing cap and discard
the old lower seal.
INSTALLATION
The service seal is a two piece, Viton seal. The
upper seal half can be installed with crankshaft
removed from engine or with crankshaft installed.
When a new upper seal is installed, install a new
lower seal. The lower seal half can be installed only
with the rear main bearing cap removed.
UPPER SEAL ÐCRANKSHAFT REMOVED
(1) Clean the cylinder block rear cap mating sur-
face. Be sure the seal groove is free of debris. Check
for burrs at the oil hole on the cylinder block mating
surface to rear cap.
(2) Lightly oil the new upper seal lips with engine
oil.
(3) Install the new upper rear bearing oil seal with
the white paint facing toward the rear of the engine.
(4) Position the crankshaft into the cylinder block.
(5) Lightly oil the new lower seal lips with engine
oil.
Fig. 29 Position Tool and Seal onto Crankshaft
1 - SPECIAL TOOL 6635
2 - OIL SEAL
3 - TIMING CHAIN COVER
Fig. 30 Installing Oil Seal
1 - SPECIAL TOOL 6635
2 - TIMING CHAIN COVER
9 - 92 ENGINE 5.2LBR/BE
CRANKSHAFT OIL SEAL - REAR (Continued)

(6) Install the new lower rear bearing oil seal into
the bearing cap with the white paint facing towards
the rear of the engine.
(7) Apply 5 mm (0.20 in.) drop of MopartGasket
Maker, or equivalent, on each side of the rear main
bearing cap (Fig. 31). DO NOT over-apply sealant or
allow the sealant to contact the rubber seal. Assem-
ble bearing cap to cylinder block immediately after
sealant application.
(8) To align the bearing cap, use cap slot, align-
ment dowel, and cap bolts. DO NOT remove excess
material after assembly. DO NOT strike rear cap
more than two times for proper engagement.
(9) Clean and oil all cap bolts. Install all main
bearing caps. Install all cap bolts and alternately
tighten to 115 N´m (85 ft. lbs.) torque.
(10) Install oil pump (Refer to 9 - ENGINE/LU-
BRICATION/OIL PUMP - INSTALLATION).
(11) Apply MopartGEN II Silicone Rubber Adhe-
sive Sealant, or equivalent, at bearing cap-to-block
joint to provide cap to block and oil pan sealing (Fig.
32). Apply enough sealant so that a small amount is
squeezed out. Withdraw nozzle and wipe excess seal-
ant off the oil pan seal groove.
(12) Install new front crankshaft oil seal (Refer to
9 - ENGINE/ENGINE BLOCK/CRANKSHAFT OIL
SEAL - FRONT - INSTALLATION).
(13) Immediately install the oil pan (Refer to 9 -
ENGINE/LUBRICATION/OIL PAN - INSTALLA-
TION).
UPPER SEALÐCRANKSHAFT INSTALLED
(1) Clean the cylinder block mating surfaces before
oil seal installation. Check for burrs at the oil hole on
the cylinder block mating surface to rear cap.
(2) Lightly oil the new upper seal lips with engine
oil. To allow ease of installation of the seal, loosen at
least the two main bearing caps forward of the rear
bearing cap.
(3) Rotate the new upper seal into the cylinder
block, being careful not to shave or cut the outer sur-
face of the seal. To ensure proper installation, use the
installation tool provided with the kit. Install the
new seal with the white paint facing toward the rear
of the engine.
(4) Install the new lower rear bearing oil seal into
the bearing cap with the white paint facing toward
the rear of the engine.
(5) Apply 5 mm (0.20 in.) drop of MopartGasket
Maker, or equivalent, on each side of the rear main
bearing cap (Fig. 31). DO NOT over-apply sealant or
allow the sealant to contact the rubber seal. Assem-
ble bearing cap to cylinder block immediately after
sealant application. Be sure the white paint faces
toward the rear of the engine.
(6) To align the bearing cap, use cap slot, align-
ment dowel, and cap bolts. DO NOT remove excess
material after assembly. DO NOT strike rear cap
more than two times for proper engagement.
(7) Install the rear main bearing cap with cleaned
and oiled cap bolts. Alternately tighten ALL cap bolts
to 115 N´m (85 ft. lbs.) torque.
(8) Install oil pump (Refer to 9 - ENGINE/LUBRI-
CATION/OIL PUMP - INSTALLATION).
Fig. 31 Sealant Application to Bearing Cap
1 - MOPAR SILICONE RUBBER ADHESIVE SEALANT SLOTS
2 - MOPARTGASKET MAKER (OR EQUIVALENT)
3 - CAP ALIGNMENT SLOT
4 - REAR MAIN BEARING CAP
Fig. 32 Apply Sealant to Bearing Cap-to-Block Joint
1 - MOPARTGEN II SILICONE RUBBER ADHESIVE SEALANT
NOZZLE TIP
2 - SEALANT APPLIED
3 - CYLINDER BLOCK
4 - REAR MAIN BEARING CAP
BR/BEENGINE 5.2L 9 - 93
CRANKSHAFT OIL SEAL - REAR (Continued)

(9) Apply MopartGEN II Silicone Rubber Adhe-
sive Sealant, or equivalent, at bearing cap-to-block
joint to provide cap-to-block and oil pan sealing (Fig.
32). Apply enough sealant until a small amount is
squeezed out. Withdraw nozzle and wipe excess seal-
ant off the oil pan seal groove.
(10)
Immediately install the oil pan (Refer to 9 -
ENGINE/LUBRICATION/OIL PAN - INSTALLATION).
LOWER SEAL
(1) Clean the rear main cap mating surfaces
including the oil pan gasket groove.
(2) Carefully install a new upper seal. Refer to
UPPER SEALÐCRANKSHAFT INSTALLED.
(3) Lightly oil the new lower seal lips with engine
oil.
(4) Install a new lower seal in bearing cap with
the white paint facing the rear of engine.
(5) Apply 5 mm (0.20 in.) drop of MopartGasket
Maker, or equivalent, on each side of the rear main
bearing cap (Fig. 31). DO NOT over-apply sealant or
allow the sealant to contact the rubber seal. Assem-
ble bearing cap to cylinder block immediately after
sealant application.
(6) To align the bearing cap, use cap slot, align-
ment dowel, and cap bolts. DO NOT remove excess
material after assembly. DO NOT strike rear cap
more than two times for proper engagement.
(7) Install the rear main bearing cap with cleaned
and oiled cap bolts. Alternately tighten the cap bolts
to 115 N´m (85 ft. lbs.) torque.
(8) Install oil pump (Refer to 9 - ENGINE/LUBRI-
CATION/OIL PUMP - INSTALLATION).
(9) Apply MopartGEN II Silicone Rubber Adhe-
sive Sealant, or equivalent, at bearing cap-to-block
joint to provide cap to block and oil pan sealing.
Apply enough sealant so that a small amount is
squeezed out. Withdraw nozzle and wipe excess seal-
ant off the oil pan seal groove.
(10)
Immediately install the oil pan (Refer to 9 -
ENGINE/LUBRICATION/OIL PAN - INSTALLATION).
DISTRIBUTOR BUSHING
REMOVAL
(1) Remove distributor (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/DISTRIBUTOR - REMOVAL).
(2) Remove the intake manifold (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
REMOVAL).
(3) Insert Distributor Drive Shaft Bushing Puller
Tool C-3052 into old bushing and thread down until a
tight fit is obtained (Fig. 33).
(4) Hold puller screw and tighten puller nut until
bushing is removed.
INSTALLATION
(1) Slide new bushing over burnishing end of Dis-
tributor Drive Shaft Bushing Driver/Burnisher Tool
C-3053. Insert the tool and bushing into the bore.
(2) Drive bushing and tool into position, using a
hammer (Fig. 34).
(3) As the burnisher is pulled through the bushing,
the bushing is expanded tight in the block and bur-
nished to correct size (Fig. 35).DO NOT ream this
bushing.
CAUTION: This procedure MUST be followed when
installing a new bushing or seizure to shaft may
occur.
Fig. 33 Distributor Driveshaft Bushing Removal
1 - SPECIAL TOOL C-3052
2 - BUSHING
Fig. 34 Distributor Driveshaft Bushing Installation
1 - SPECIAL TOOL C-3053
2 - BUSHING
9 - 94 ENGINE 5.2LBR/BE
CRANKSHAFT OIL SEAL - REAR (Continued)

(4) Install the intake manifold (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
INSTALLATION).
(5) Install the distributor (Refer to 8 - ELECTRI-
CAL/IGNITION CONTROL/DISTRIBUTOR -
INSTALLATION).
HYDRAULIC LIFTERS (CAM IN
BLOCK)
DIAGNOSIS AND TESTINGÐHYDRAULIC
TAPPETS
Before disassembling any part of the engine to cor-
rect tappet noise, check the oil pressure. If vehicle
has no oil pressure gauge, install a reliable gauge at
the pressure sending-unit. The pressure should be
between 207-552 kPa (30-80 psi) at 3,000 RPM.
Check the oil level after the engine reaches normal
operating temperature. Allow 5 minutes to stabilize
oil level, check dipstick. The oil level in the pan
should never be above the FULL mark or below the
ADD OIL mark on dipstick. Either of these two con-
ditions could be responsible for noisy tappets.
OIL LEVEL
HIGH
If oil level is above the FULL mark, it is possible
for the connecting rods to dip into the oil. With the
engine running, this condition could create foam in
the oil pan. Foam in oil pan would be fed to the
hydraulic tappets by the oil pump causing them to
lose length and allow valves to seat noisily.LOW
Low oil level may allow oil pump to take in air.
When air is fed to the tappets, they lose length,
which allows valves to seat noisily. Any leaks on
intake side of oil pump through which air can be
drawn will create the same tappet action. Check the
lubrication system from the intake strainer to the
pump cover, including the relief valve retainer cap.
When tappet noise is due to aeration, it may be
intermittent or constant, and usually more than one
tappet will be noisy. When oil level and leaks have
been corrected, operate the engine at fast idle. Run
engine for a sufficient time to allow all of the air
inside the tappets to be bled out.
TAPPET NOISE DIAGNOSIS
(1) To determine source of tappet noise, operate
engine at idle with cylinder head covers removed.
(2) Feel each valve spring or rocker arm to detect
noisy tappet. The noisy tappet will cause the affected
spring and/or rocker arm to vibrate or feel rough in
operation.
NOTE: Worn valve guides or cocked springs are
sometimes mistaken for noisy tappets. If such is
the case, noise may be dampened by applying side
thrust on the valve spring. If noise is not apprecia-
bly reduced, it can be assumed the noise is in the
tappet. Inspect the rocker arm push rod sockets
and push rod ends for wear.
(3) Valve tappet noise ranges from light noise to a
heavy click. A light noise is usually caused by exces-
sive leak-down around the unit plunger, or by the
plunger partially sticking in the tappet body cylinder.
The tappet should be replaced. A heavy click is
caused by a tappet check valve not seating, or by for-
eign particles wedged between the plunger and the
tappet body. This will cause the plunger to stick in
the down position. This heavy click will be accompa-
nied by excessive clearance between the valve stem
and rocker arm as valve closes. In either case, tappet
assembly should be removed for inspection and clean-
ing.
(4) The valve train generates a noise very much
like a light tappet noise during normal operation.
Care must be taken to ensure that tappets are mak-
ing the noise. If more than one tappet seems to be
noisy, it's probably not the tappets.
LEAK-DOWN TEST
After cleaning and inspection, test each tappet for
specified leak-down rate tolerance to ensure zero-lash
operation (Fig. 36).
Swing the weighted arm of the hydraulic valve tap-
pet tester away from the ram of the Universal Leak-
Down Tester.
Fig. 35 Burnishing Distributor Driveshaft Bushing
1 - SPECIAL TOOL C-3053
2 - BUSHING
BR/BEENGINE 5.2L 9 - 95
DISTRIBUTOR BUSHING (Continued)