2001 DODGE RAM Valve

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 thetappet. 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. 38).
Swing the weighted arm of the hydraulic valve tap-
pet tester away from the ram of the Universal Leak-
Down Tester.
(1) Place a 7.925-7.950 mm (0.312-0.313 inch)
diameter ball bearing on the plunger cap of the tap-
pet.
(2) Lift the ram and position the tappet (with the
ball bearing) inside the tester cup.
(3) Lower the ram, then adjust the nose of the ram
until it contacts the ball bearing. DO NOT tighten
the hex nut on the ram.
(4) Fill the tester cup with hydraulic valve tappet
test oil until the tappet is completely submerged.
(5) Swing the weighted arm onto the push rod and
pump the tappet plunger up and down to remove air.
When the air bubbles cease, swing the weighted arm
away and allow the plunger to rise to the normal
position.
(6) Adjust the nose of the ram to align the pointer
with the SET mark on the scale of the tester and
tighten the hex nut.
(7) Slowly swing the weighted arm onto the push
rod.
(8) Rotate the cup by turning the handle at the
base of the tester clockwise one revolution every 2
seconds.
(9) Observe the leak-down time interval from the
instant the pointer aligns with the START mark on
the scale until the pointer aligns with the 0.125
mark. A normally functioning tappet will require
9 - 38 ENGINE 3.9LBR/BE

20-110 seconds to leak-down. Discard tappets with
leak-down time interval not within this specification.
REMOVAL
(1) Remove the air cleaner assembly and air in-let
hose.
(2) Remove cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
(3) Remove rocker assembly and push rods. Iden-
tify push rods to ensure installation in original loca-
tions.
(4) Remove intake manifold (Refer to 9 - ENGINE/
MANIFOLDS/INTAKE MANIFOLD - REMOVAL).(5) Remove yoke retainer and aligning yokes.
(6) Slide Hydraulic Tappet Remover/Installer Tool
C-4129-A through opening in cylinder head and seat
tool firmly in the head of tappet.
(7) Pull tappet out of bore with a twisting motion.
If all tappets are to be removed, identify tappets to
ensure installation in original location.
(8) If the tappet or bore in cylinder block is scored,
scuffed, or shows signs of sticking, ream the bore to
next oversize. Replace with oversize tappet.
CLEANING
Clean tappet with a suitable solvent. Rinse in hot
water and blow dry with a clean shop rag or com-
pressed air.
INSTALLATION
(1) Lubricate tappets.
(2) Install tappets and push rods in their original
positions. Ensure that the oil feed hole in the side of
the tappet body faces up (away from the crankshaft).
(3) Install aligning yokes with ARROW toward
camshaft.
(4) Install yoke retainer. Tighten the bolts to 23
N´m (200 in. lbs.) torque. Install intake manifold
(Refer to 9 - ENGINE/MANIFOLDS/INTAKE MANI-
FOLD - INSTALLATION).
(5) Install push rods in original positions.
(6) Install rocker arms.
(7) Install cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION).
(8) Install air cleaner assembly and air in-let hose.
(9) Start and operate engine. Warm up to normal
operating temperature.
CAUTION: To prevent damage to valve mechanism,
engine must not be run above fast idle until all
hydraulic tappets have filled with oil and have
become quiet.
Fig. 38 Leak-Down Tester
1 - POINTER
2 - WEIGHTED ARM
3 - RAM
4 - CUP
5 - HANDLE
6 - PUSH ROD
BR/BEENGINE 3.9L 9 - 39
HYDRAULIC LIFTERS (CAM IN BLOCK) (Continued)

(3) Using the transmission jack, lower the trans-
mission and support cushion onto the crossmember
(Fig. 49).
(4) Install the support cushion bolts and tighten to
41 N´m (30 ft. lbs.) torque.
(5) Remove the transmission jack.
(6) Lower the vehicle.
LUBRICATION
DESCRIPTION
A gear-type positive displacement pump (Fig. 50)is
mounted at the underside of the rear main bearing
cap. The pump uses a pick-up tube and screen
assembly to gather engine oil from the oil pan.
OPERATION
The pump draws oil through the 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
pump body, then forced through the outlet to the
block. An oil gallery in the block channels the oil to
the inlet side of the full flow oil filter. After passing
through the filter element, the oil passes from the
center outlet of the filter through an oil gallery that
channels the oil up to the main gallery, which
extends the entire length on the right side of the
block. The oil then goes down to the No. 1 main bear-
ing, back up to the left side of the block, and into the
oil gallery on the left side of the engine.
Galleries extend downward from the main oil gal-
lery to the upper shell of each main bearing. The
crankshaft is drilled internally to pass oil from the
main bearing journals to the connecting rod journals.
Each connecting rod bearing has half a hole in it, oil
passes through the hole when the rods rotate and the
hole lines up, oil is then thrown off as the rod
rotates. This oil throwoff lubricates the camshaft
lobes, distributor drive gear, cylinder walls, and pis-
ton pins.The hydraulic valve tappets receive oil directly
from the main oil gallery. The camshaft bearings
receive oil from the main bearing galleries. The front
camshaft bearing journal passes oil through the cam-
shaft sprocket to the timing chain. Oil drains back to
the oil pan under the No. 1 main bearing cap.
The oil supply for the rocker arms and bridged
pivot assemblies is provided by the hydraulic valve
tappets, which pass oil through hollow push rods to a
hole in the corresponding rocker arm. Oil from the
rocker arm lubricates the valve train components.
The oil then passes down through the push rod guide
holes and the oil drain-back passages in the cylinder
head, past the valve tappet area, and then returns to
the oil pan (Fig. 51).
Fig. 50 Positive Displacement Oil PumpÐTypical
1 - INNER ROTOR AND SHAFT
2 - BODY
3 - DISTRIBUTOR DRIVESHAFT (REFERENCE)
4 - COTTER PIN
5 - RETAINER CAP
6 - SPRING
7 - RELIEF VALVE
8 - LARGE CHAMFERED EDGE
9 - BOLT
10 - COVER
11 - OUTER ROTOR
BR/BEENGINE 3.9L 9 - 45
REAR MOUNT (Continued)

Fig. 51 Oil Lubrication System
1 - OIL DEFLECTOR TAB
2 - BOLT
3 - ROCKER ARM PIVOT
4 - ROCKER ARM
5 - DRIP OILING FOR VALVE TIP
6 - CYLINDER HEAD BOSS
7 - TO MAIN BEARINGS
8 - TO CAMSHAFT BEARINGS
9 - ROCKER ARM
10 - HOLLOW PUSH ROD
11 - TAPPET
12 - TO CONNECTING ROD BEARINGS
13 - OIL INTAKE14 - OIL PUMP
15 - OIL FILTER
16 - CRANKSHAFT
17 - FROM OIL PUMP
18 - OIL TO FILTER
19 - OIL FROM FILTER TO SYSTEM
20 - PASSAGE TO CAMSHAFT REAR BEARING
21 - RIGHT OIL GALLERY
22 - PLUG
23 - OIL PASSAGE FOR OIL PRESSURE INDICATOR LIGHT
24 - OIL SUPPLY VIA HOLLOW PUSH ROD SUPPLY IS FROM
OIL GALLERY METERED THROUGH HYDRAULIC TAPPET
25 - OIL SUPPLY FROM HOLLOW PUSH ROD
9 - 46 ENGINE 3.9LBR/BE
LUBRICATION (Continued)

DIAGNOSIS AND TESTINGÐENGINE OIL
PRESSURE
(1) Remove oil pressure sending unit.
(2) Install Oil Pressure Line and Gauge Tool
C-3292. Start engine and record pressure. (Refer to 9
- ENGINE - SPECIFICATIONS).
DIAGNOSIS AND TESTINGÐENGINE OIL
LEAKS
Begin with a through visual inspection of the
engine, particularly at the area of the suspected leak.
If an oil leak source is not readily identifiable, the
following steps should be followed:
(1) Do not clean or degrease the engine at this
time because some solvents may cause rubber to
swell, temporarily stopping the leak.
(2) Add an oil-soluble dye (use as recommended by
manufacturer). Start the engine and let idle for
approximately 15 minutes. Check the oil dipstick to
be sure the dye is thoroughly mixed as indicated
with a bright yellow color under a black light source.
(3) Using a black light, inspect the entire engine
for fluorescent dye, particularly at the suspected area
of oil leak. If the oil leak is found and identified,
repair per service manual instructions.
(4) If dye is not observed, drive the vehicle at var-
ious speeds for approximately 24km (15 miles), and
repeat previous step.
(5) If the oil leak source is not positively identified
at this time, proceed with the air leak detection test
method as follows:
(6) Disconnect the breather cap to air cleaner hose
at the breather cap end. Cap or plug breather cap
nipple.
(7) Remove the PCV valve from the cylinder head
cover. Cap or plug the PCV valve grommet.
(8) Attach an air hose with pressure gauge and
regulator to the dipstick tube.
CAUTION: Do not subject the engine assembly to
more than 20.6 kpa (3 PSI) of test pressure.
(9) Gradually apply air pressure from 1 psi to 2.5
psi maximum while applying soapy water at the sus-
pected source. Adjust the regulator to the suitable
test pressure that provide the best bubbles which
will pinpoint the leak source. If the oil leak is
detected and identified, repair per service manual
procedures.
(10) If the leakage occurs at the rear oil seal area,
refer to the section, Inspection for Rear Seal Area
Leak.
(11) If no leaks are detected, turn off the air sup-
ply and remove the air hose and all plugs and caps.
Install the PCV valve and breather cap hose. Proceed
to next step.(12) Clean the oil off the suspect oil leak area
using a suitable solvent. Drive the vehicle at various
speeds approximately 24 km (15 miles). Inspect the
engine for signs of an oil leak by using a black light.
OIL
STANDARD PROCEDUREÐENGINE OIL
OIL LEVEL INDICATOR (DIPSTICK)
The engine oil level indicator is located at the right
front of the engine, left of the generator on 3.9L
engines (Fig. 52).
CRANKCASE OIL LEVEL INSPECTION
CAUTION: Do not overfill crankcase with engine oil,
oil foaming and oil pressure loss can result.
To ensure proper lubrication of an engine, the
engine oil must be maintained at an acceptable level.
The acceptable levels are indicated between the ADD
and SAFE marks on the engine oil dipstick.
(1) Position vehicle on level surface.
(2) With engine OFF, allow approximately ten min-
utes for oil to settle to bottom of crankcase, remove
engine oil dipstick.
(3) Wipe dipstick clean.
(4) Install dipstick and verify it is seated in the
tube.
(5) Remove dipstick, with handle held above the
tip, take oil level reading.
Fig. 52 Oil Level Indicator Location
1 - CYLINDER HEAD COVER
2 - ENGINE OIL FILL CAP
3 - DIPSTICK
4 - ENGINE OIL FILTER
5 - FILTER BOSS
BR/BEENGINE 3.9L 9 - 47
LUBRICATION (Continued)

OIL PUMP
REMOVAL
(1) Remove the oil pan (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - REMOVAL).
(2)
Remove the oil pump from rear main bearing cap.
DISASSEMBLE
(1) Remove the relief valve as follows:
(a) Remove cotter pin. Drill a 3.175 mm (1/8 in.)
hole into the relief valve retainer cap and insert a
self-threading sheet metal screw into cap.
(b) Clamp screw into a vise and while support-
ing oil pump, remove cap by tapping pump body
using a soft hammer. Discard retainer cap and
remove spring and relief valve (Fig. 57).
(2) Remove oil pump cover (Fig. 58).
(3) Remove pump outer rotor and inner rotor with
shaft (Fig. 58).
(4) Wash all parts in a suitable solvent and inspect
carefully for damage or wear.
CLEANING
Use only mild solvents to clean the oil pump. Do
not use any abrasive material to clean the oil pump
housing or rotors.
INSPECTION
Mating surface of the oil pump cover should be
smooth. Replace pump assembly if cover is scratched
or grooved.Lay a straightedge across the pump cover surface
(Fig. 59). If a 0.038 mm (0.0015 in.) feeler gauge can
be inserted between cover and straightedge, pump
assembly should be replaced.
Fig. 57 Oil Pressure Relief Valve
1 - OIL PUMP ASSEMBLY
2 - COTTER PIN
3 - RELIEF VALVE
4 - RETAINER CAP
5 - SPRING
Fig. 58 Oil Pump
1 - INNER ROTOR AND SHAFT
2 - BODY
3 - DISTRIBUTOR DRIVESHAFT (REFERENCE)
4 - COTTER PIN
5 - RETAINER CAP
6 - SPRING
7 - RELIEF VALVE
8 - LARGE CHAMFERED EDGE
9 - BOLT
10 - COVER
11 - OUTER ROTOR
Fig. 59 Checking Oil Pump Cover Flatness
1 - COVER
2 - STRAIGHT EDGE
3 - FEELER GAUGE
9 - 50 ENGINE 3.9LBR/BE

Measure thickness and diameter of outer rotor. If
outer rotor thickness measures 20.9 mm (0.825 in.)
or less, or if the diameter is 62.7 mm (2.469 in.) or
less, replace outer rotor (Fig. 60).
If inner rotor measures 20.9 mm (0.825 in.) or less,
replace inner rotor and shaft assembly (Fig. 61).
Slide outer rotor into pump body. Press rotor to the
side with your fingers and measure clearance
between rotor and pump body (Fig. 62). If clearance
is 0.356 mm (0.014 in.) or more, replace oil pump
assembly.
Install inner rotor and shaft into pump body. If
clearance between inner and outer rotors is 0.203
mm (0.008 in.) or more, replace shaft and both rotors
(Fig. 63).
Place a straightedge across the face of the pump,
between bolt holes. If a feeler gauge of 0.102 mm
(0.004 in.) or more can be inserted between rotors
and the straightedge, replace pump assembly (Fig.
64).
Inspect oil pressure relief valve plunger for scoring
and free operation in its bore. Small marks may be
removed with 400-grit wet or dry sandpaper.The relief valve spring has a free length of approx-
imately 49.5 mm (1.95 in.). The spring should test
between 19.5 and 20.5 pounds when compressed to
34 mm (1-11/32 in.). Replace spring that fails to meet
these specifications (Fig. 65).
If oil pressure was low and pump is within specifi-
cations, inspect for worn engine bearings or other
reasons for oil pressure loss.
ASSEMBLY
(1) Install pump rotors and shaft, using new parts
as required.
(2) Position the oil pump cover onto the pump
body. Tighten cover bolts to 11 N´m (95 in. lbs.)
torque.
Fig. 60 Measuring Outer Rotor Thickness
Fig. 61 Measuring Inner Rotor Thickness
Fig. 62 Measuring Outer Rotor Clearance in
Housing
1 - PUMP BODY
2 - OUTER ROTOR
3 - FEELER GAUGE
Fig. 63 Measuring Clearance Between Rotors
1 - OUTER ROTOR
2 - FEELER GAUGE
3 - INNER ROTOR
BR/BEENGINE 3.9L 9 - 51
OIL PUMP (Continued)

(3) Install the relief valve and spring. Insert the
cotter pin.
(4) Tap on a new retainer cap.
(5) Prime oil pump before installation by filling
rotor cavity with engine oil.
INSTALLATION
(1) Install oil pump. During installation, slowly
rotate pump body to ensure driveshaft-to-pump rotor
shaft engagement.(2) Hold the oil pump base flush against mating
surface on No. 4 main bearing cap. Finger-tighten
pump attaching bolts. Tighten attaching bolts to 41
N´m (30 ft. lbs.) torque.
(3) Install the oil pan (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - INSTALLATION).
INTAKE MANIFOLD
DESCRIPTION
The aluminum intake manifold (Fig. 66) is a single
plane design with equal length runners. This mani-
fold uses a separate plenum pan and gasket, there-
fore the plenum gasket is servicable. It also uses
separate flange gaskets and front and rear cross-over
gaskets. Extreme care must be used when sealing
the gaskets to ensure that excess sealant does not
enter the intake runners causing a restriction.
OPERATION
The intake manifold, meters and delivers air to the
combustion chambers allowing the fuel delivered by
the fuel injectors to ignite, thus producing power.
Fig. 64 Measuring Clearance Over Rotors
1 - STRAIGHT EDGE
2 - FEELER GAUGE
Fig. 65 Proper Installation of Retainer Cap
1 - RETAINER CAP
2 - CHAMFER
3 - COTTER KEY
Fig. 66 Intake Manifold with Tightening SequenceÐ
3.9L Engine
9 - 52 ENGINE 3.9LBR/BE
OIL PUMP (Continued)