1996 CHRYSLER VOYAGER oil pressure

GENERAL SPECIFICATION
Type .............In-Line OHV, DOHC & SOHC
Bore.....................87.5mm (3.445 Inch)
Stroke...................83.0mm (3.268 inch)
Compression Ratio....DOHC - 9.6:1 SOHC - 9.8:1
Displacement.........2.0Liters (122 Cubic Inch)
Firing Order........................1,3,4,2
Compression Pressure...........1172-1551 kPa
(170 - 225 psi)
Maximum Variation Between Cylinders......25%
Lubrication . . . Pressure Feed - Full Flow Filtration
(Crankshaft Driven Pump)
Engine Oil Capacity . . Refer to Group 0, Lubrication
and Maintenance
ENGINE LUBRICATION SYSTEM
ENGINE LUBRICATION
Refer to Group 0, Lubrication and Maintenance for
recommended oil to be used in various engine appli-
cation. System is full flow filtration, pressure feed
type. The oil pump is mounted in the front engine
cover and driven by the crankshaft. Pressurized oil is
then routed through the main oil gallery, running the
length of the cylinder block, supplying main and rodbearings with further routing. Rod bearing oil throw-
off lubricates the pistons from directed slots on the
side of the connecting rod assemblies. Camshaft and
valve mechanisms are lubricated from a full-length
cylinder head oil gallery supplied from the crankcase
main oil gallery.
PRESSURE LUBRICATION
Oil drawn up through the pickup tube is pressur-
ized by the pump and routed through the full flow fil-
ter to the main oil gallery running the length of the
cylinder block. A cylinder head restrictor, located in
the block, provides increased oil flow to the main oil
gallery (Fig. 2).
MAIN/ROD BEARINGS
A diagonal hole in each bulkhead feeds oil to each
main bearing. Drilled passages within the crankshaft
route oil from main bearing journals to connecting
rod journals.
CAMSHAFT/HYDRAULIC LASH ADJUSTERS
A vertical hole at the number five bulkhead routes
pressurized oil through a restrictor up into the cylin-
der head. The rocker shafts route oil to the rocker
arms/hydraulic lash adjuster assemblies.
Engine Lubrication Components
9 - 2 ENGINENS/GS
DESCRIPTION AND OPERATION (Continued)

SPLASH LUBRICATION
Oil returning to the pan from pressurized compo-
nents supplies lubrication to the valve stems. Cylin-
der bores and wrist pins are splash lubricated from
directed slots on the connecting rod thrust collars.
ENGINE COMPONENTS
CYLINDER BLOCK AND BEDPLATE ASSEM-
B LY:A partial open deck is used for cooling and
weight reduction with water pump molded into the
block. Nominal wall thickness is 4 mm. The bedplate
incorporates main bearing caps. Rear seal retainer is
integral with the block.
CRANKSHAFT:A nodular cast iron crankshaft is
used. The engine has 5 main bearings, with number
3 flanged to control thrust. The 52 mm diameter
main and 48 mm diameter crank pin journals (all)
have undercut fillet radiuses that are deep rolled for
added strength. To optimize bearing loading 8 coun-
terweights are used. Hydrodynamic seals provide end
sealing, where the crankshaft exits the block.
Anaerobic gasket material is used for parting line
sealing. A sintered iron timing belt sprocket is
mounted on the crankshaft nose. This sprocket trans-
mits crankshaft movement, via timing belt to the
camshaft sprocket providing timed valve actuation.
PISTONS:The SOHC EngineDOES NOThave
provision for a free wheeling valve train. Non free
wheeling valve train means, in the event of a broken
timing belt Pistons will contact the Valves. All
engines use pressed-in piston pins to attach forged
powdered metal connecting rods. The connecting rods
are a cracked cap design and are not repairable. Hexhead cap screw are used to provide alignment and
durability in the assembly. Pistons And Connecting
rods are serviced as an assembly.
PISTON RINGS:The piston rings include a
molybdenum faced top ring for reliable compression
sealing and a taper faced intermediate ring for addi-
tional cylinder pressure control. Oil Control Ring
Package consist of 2 steel rails and a expander
spacer.
CYLINDER HEADÐSOHC:It features a Single
Over Head Camshaft, four-valves per cylinder cross
flow design. The valves are arranged in two inline
banks, with the two intake per cylinder facing
toward the radiator. The exhaust valves facing
toward the dash panel. Rocker arm shafts mount
directly to the cylinder head. It incorporates powder
metal valve guides and seats. The hollow rocker arm
shafts supplies oil to the hydraulic lash adjusters,
camshaft and valve mechanisms.
CAMSHAFTÐSOHC:The nodular iron camshaft
has five bearing journals and 3 cam lobes per cylin-
der. Provision for cam position sensor on the cam at
the rear of cylinder head which also acts as thrust
plate. A hydrodynamic oil seal is used for oil control
at the front of the camshaft.
VALVESÐSOHC:Four valves per cylinder are
actuated by roller rocker arms/hydraulic lash adjust-
ers assemblies which pivot on rocker arm shafts. All
valves have 6 mm diameter chrome plated valve
stems. The valve train has 33 mm (1.299 inch) diam-
eter intake valves and 28 mm (1.10 inch) diameter
exhaust valves. Viton rubber valve stem seals are
integral with spring seats. Valve springs, spring
retainers, and locks are conventional design.
INTAKE MANIFOLD:The intake manifold is a
molded plastic composition, attached to the cylinder
head with ten fasteners. This long branch design
enhances low and mid-range torque.
EXHAUST MANIFOLD:The exhaust manifold is
made of nodular cast iron for strength and high tem-
peratures. Exhaust gasses exit through a machined,
articulated joint connection to the exhaust pipe.
DIAGNOSIS AND TESTING
CHECKING ENGINE OIL PRESSURE
(1) Remove oil pressure switch and install gauge
assembly C-3292 with adaptor.
(2) Run engine until thermostat opens.
CAUTION: If oil pressure is 0 at idle, Do Not per-
form the 3000 RPM test in the next step.
(3) Oil Pressure:Curb Idle25 kPa (4 psi) mini-
mum3000 RPM170-550 kPa (25-80 psi).
Fig. 2 Engine Lubrication SystemÐ SOHC
NS/GSENGINE 9 - 3
DESCRIPTION AND OPERATION (Continued)

(4) If oil pressure is 0 at idle. Shut off engine,
check for pressure relief valve stuck open, a clogged
oil pick-up screen or a damaged oil pick-up tube
O-ring.
SERVICE PROCEDURES
CYLINDER BORE AND PISTON SIZING
The cylinder walls should be checked for out-of-
round and taper with Tool C-119 (Fig. 3). The cylin-
der bore out-of-round is 0.050 mm (.002 inch)
maximum and cylinder bore taper is 0.051 mm (0.002
inch) maximum. If the cylinder walls are badly
scuffed or scored, the cylinder block should be
rebored and honed, and new pistons and rings fitted.
Whatever type of boring equipment is used, boring
and honing operation should be closely coordinated
with the fitting of pistons and rings in order that
specified clearances may be maintained.Refer to
Honing Cylinder Bores outlined in the Stan-
dard Service Procedures for specification and
procedures.
Measure the cylinder bore at three levels in direc-
tions A and B (Fig. 3). Top measurement should be
10 mm (3/8 inch) down and bottom measurement
should be 10 mm (3/8 inch.) up from bottom of bore.
Refer to Cylinder Bore and Piston Specifications
Chart.
SIZING PISTONS
Piston and cylinder wall must be clean and dry.
Piston diameter should be measured 90 degrees to
piston pin about 17.5 mm (11/16 inch) from the bot-tom of the skirt as shown in (Fig. 4). Cylinder bores
should be measured halfway down the cylinder bore
and transverse to the engine crankshaft center line
shown in (Fig. 3). Refer to Cylinder Bore and Speci-
fications Table. Correct piston to bore clearance must
be established in order to assure quiet and economi-
cal operation.
Chrysler engines use pistons designed specifically
for each engine model. Clearance and sizing locations
vary with respect to engine model.
NOTE: Pistons and cylinder bores should be mea-
sured at normal room temperature, 21ÉC (70ÉF).
FITTING PISTON RINGS
(1) Wipe cylinder bore clean. Insert ring and push
down with piston to ensure it is square in bore. The
ring gap measurement must be made with the ring
positioning at least 12 mm (0.50 inch) from bottom of
cylinder bore. Check gap with feeler gauge (Fig. 5).
Refer to Piston Ring Specification Chart.
Fig. 3 Checking Cylinder Bore Size
CYLINDER BORE AND PISTON
SPECIFICATION CHART
Standard Bore Maximum
Out-of-RoundMaximum
Taper
87.5 mm
(3.445 in.)0.051 mm
(0.002 in.)0.051 mm
(0.002 in.)
Standard Piston Size
Federal
Emission:87.463 - 87.481 mm
(3.4434 - 3.4441 in.)
Low Emission
Vehicle (LEV):87.456 - 87.474 mm
(3.4432 - 3.4439 in.)
Piston to Bore Clearance
Federal
Emission:0.012 - 0.044 mm
(0.0004 - 0.0017 in.)
Low Emission
Vehicle (LEV):0.18 - 0.050 mm
(0.0008 - 0.0020 in.)
Measurements Taken at Piston Size Location
Fig. 4 Piston Measurements
9 - 4 ENGINENS/GS
DIAGNOSIS AND TESTING (Continued)

SPARK PLUG TUBE
(1) Remove valve cover. Refer to procedure out-
lined in this section.
(2) Using locking pliers remove the tube from the
cylinder head (Fig. 11). Discard old tube.
(3) Clean area around spark plug with Mopart
parts cleaner or equivalent.
(4) Apply MopartStud and Bearing Mount or
equivalent to a new tube approximately 1 mm from
theendina3mmwide area.
(5) Install sealer end of tube into the cylinder
head. Then carefully install the tube using a hard-
wood block and mallet until the tube is seated into
the bottom of the bore.
(6) Install valve cover. Refer to procedure outlined
in this section.
SPARK PLUG TUBE SEALS
The spark plug tube seals are located in the cylin-
der head cover (Fig. 12). These seals are pressed into
the cylinder head cover to seal the outside perimeterof the spark plug tubes. If these seals show signs of
hardness and/or cracking they should be replaced.
CAMSHAFT
NOTE: TO REMOVE CAMSHAFT THE CYLINDER
HEAD MUST BE REMOVED.
REMOVAL
(1) Perform fuel system pressure release procedure
before attempting any repairs.Refer to Group 14,
Fuel System
(2) Remove the cylinder head cover. Refer to proce-
dure outlined in this section.
(3) Mark rocker arm shaft assemblies so that they
are installed in their original positions.
(4) Remove rocker arm shaft bolts. Refer to proce-
dure outlined in this section.
(5) Remove timing belt, timing belt tensioner, and
camshaft sprocket. Refer to timing belt service out-
lined in this section.
(6) Remove inner timing belt cover.
(7) Remove cylinder head. Refer to procedure out-
lined in this section.
(8) Remove camshaft sensor and camshaft target
magnet.
(9) Remove camshaft from the rear of cylinder
head.
INSPECT CYLINDER HEAD FOR THE FOLLOWING:
NOTE:
²Check oil feed holes for blockage.
²Inspect cylinder head camshaft bearings for
wear, Refer to Cylinder Head, Inspection and Clean-
ing.
²Check camshaft bearing journals for scratches
and worn areas. If light scratches are present, they
may be removed with 400 grit sand paper. If deep
Fig. 10 Ingition Coil Pack
Fig. 11 Servicing Spark Plug Tubes
Fig. 12 Spark Plug Tube Seals
NS/GSENGINE 9 - 7
REMOVAL AND INSTALLATION (Continued)

HYDRAULIC LASH ADJUSTER NOISE
A tappet-like noise may be produced from several
items. Refer to Lash Adjuster Noise - Diagnosis in
Standard Service Procedures, outlined in this Group.
Lash adjusters are replaced with the rocker
arm as an assembly.
VALVE SEALS AND SPRINGS IN VEHICLE
REMOVAL
(1) Remove rocker arm shafts assemblies as previ-
ously outlined in this section.
(2) Rotate crankshaft until piston is at TDC on
compression.
(3) With air hose attached to adapter tool installed
in spark plug hole, apply 90-120 psi air pressure.
(4) Using Special Tool MD-998772A with adapter
6779 (Fig. 19) compress valve springs and remove
valve locks.
(5) Remove valve spring.
(6) Remove valve stem seal by using a valve stem
seal tool (Fig. 20).
INSTALLATION
(1) Install valve seal/valve spring seat assembly
as outlined in the Valve Installation procedure in this
section.
(2) Using Special Tool MD-998772A compress valve
springs only enough to install locks. Correct align-
ment of tool is necessary to avoid nicking valve stems
(air pressure required), piston at TDC.
(3) Install rocker arm shaft assemblies as previ-
ously outlined in this section.
(4) Install valve cover as previously outlined in
this section.
CYLINDER HEAD
REMOVAL
(1) Perform fuel system pressure release procedure
before attempting any repairs.Refer to Group 14,
Fuel System
(2) Disconnect negative battery cable. Drain cool-
ing system. Refer to Group 7, Cooling System.
(3) Disconnect all vacuum lines, electrical wiring
and fuel lines from throttle body.
(4) Remove throttle linkage.
(5) Remove accessory drive belts. Refer to Group 7,
Cooling System for procedure.
(6) Remove power brake vacuum hose from intake
manifold.
(7) Raise vehicle and remove exhaust pipe from
manifold.
(8) Remove power steering pump assembly and set
aside.
(9) Disconnect coil pack wiring connector and
remove coil pack and bracket from engine.
(10) Remove cylinder head cover.
(11) Remove cam sensor and fuel injectors wiring
connectors.
(12) Remove intake manifold. Removal procedure
outline in Group 11.
Fig. 19 Removing and Installing Valve Spring
Fig. 20 Valve Stem Oil Seal Tool
Fig. 21 Valve Spring Assembly
9 - 10 ENGINENS/GS
REMOVAL AND INSTALLATION (Continued)

INSTALLATION
(1) Install crankshaft damper using M12-1.75 x
150 mm bolt, washer, thrust bearing and nut from
Special Tool 6792. Install crankshaft damper bolt and
tighten to 142 N´m (105 ft. lbs.) (Fig. 84).
(2) Install accessory drive belts. Refer to Group 7,
Cooling System Accessory Drive section for proce-
dure.
DISASSEMBLY AND ASSEMBLY
OIL PUMP
(1) To remove the relief valve, proceed as follows:
(2) Remove the threaded plug and gasket from the
oil pump (Fig. 85).
CAUTION: Oil pump pressure relief valve must be
installed as shown in (Fig. 85) or serious damage
may occur.
(3) Remove spring and relief valve (Fig. 85).(4) Remove oil pump cover screws, and lift off
cover.
(5) Remove pump rotors.
(6) Wash all parts in a suitable solvent and inspect
carefully for damage or wear (Fig. 86).
VALVE SERVICE WITH THE CYLINDER HEAD
REMOVED
REMOVAL
(1) With cylinder head removed, compress valve
springs using Special Tool C-3422-B or equivalent.
(2) Remove valve retaining locks, valve spring
retainers, valve stem seals and valve springs.
(3) Before removing valves,remove any burrs
from valve stem lock grooves to prevent dam-
age to the valve guides.Identify valves to insure
installation in original location.
VALVE INSPECTION
(1) Clean valves thoroughly and discard burned,
warped and cracked valves.
(2) Measure valve stems for wear. Measure stem
about 60 mm beneath the valve lock grooves.
(3) If valve stems are worn more than 0.05 mm
(.002 in.), replace valve.
VALVE GUIDES
(1) Remove carbon and varnish deposits from
inside of valve guides with a reliable guide cleaner.
(2) Using a small hole gauge and a micrometer,
measure valve guides in 3 places top, middle and bot-
tom (Fig. 87). Refer to Valve Guide Specification
Chart for specifications. Replace guides if they are
not within specification.
(3) Check valve guide height (Fig. 88).
TESTING VALVE SPRINGS
(1) Whenever valves have been removed for inspec-
tion, reconditioning or replacement, valve springs
Fig. 84 Crankshaft DamperÐInstallation
Fig. 85 Oil Pressure Relief Valve
Fig. 86 Oil Pump
NS/GSENGINE 9 - 29
REMOVAL AND INSTALLATION (Continued)

Total runout should not exceed. 0.051 mm (0.002
inch.) (total indicator reading).
(5) Inspect the valve seat with Prussian blue to
determine where the valve contacts the seat. To do
this, coat valve seatLIGHTLYwith 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 top edge of the valve face, lower valve seat
with a 15 degrees stone. If the blue is transferred to
the bottom edge of valve face raise valve seat with a
65 degrees stone.
²Intake valve seat diameter is 33 mm (1.299 in.)
²Exhaust valve seat diameter is 28 mm (1.102
in.)
(6) Valve seats which are worn or burned can be
reworked, provided that correct angle and seat width
are maintained. The intake valve seat must be ser-
viced when the valve seat width is 2.0 mm (0.079 in.)
or greater. The exhaust valve seat must be serviced
when the valve seat width is 2.5 mm (0.098 in.) or
greater. Otherwise the cylinder head must be
replaced.
(7) When seat is properly positioned the width of
intake and exhaust seats should be 0.75 to 1.25 mm
(0.030 to 0.049 in.) (Fig. 91).
(8) Check valve tip to spring seat dimensions A
after grinding the valve seats or faces. Grind valve
tip to 43.51 - 44.57 mm (1.71 - 1.75 in.) for exhaust
valve and 45.01 - 46.07 mm (1.77 - 1.81 in.) for
intake valve over spring seat when installed in the
head (Fig. 92). The valve tip chamfer may need to be
reground to prevent seal damage when the valve is
installed.
CLEANING
Clean all valve guides, valves and valve spring
assemblies thoroughly with suitable cleaning solution
before reassembling.
VALVE INSTALLATION
(1) Coat valve stems with clean engine oil and
insert in cylinder head.
(2) Install new valve stem seals on all valves using
a valve stem seal tool (Fig. 93). The valve stem seals
should be pushed firmly and squarely over valve
guide.
CAUTION: If oversize valves are used, there is only
one oversize valve available. The same stem seal is
used on both the standard and oversize valve.
(3) Install valve springs and retainers. Compress
valve springs only enough to install locks, taking
care not to misalign the direction of compression.
Nicked valve stems may result from misalignment of
the valve spring compressor.
VALVE SPECIFICATION CHART
Face Angle
Intake and
Exhaust:45 - 45 1/2É
Head Diameter
Intake: 33.12 - 33.37 mm (1.303 - 1.313 in.)
Exhaust: 28.57 - 28.83 mm (1.124 - 1.135 in.)
Length (Overall)
Intake: 114.69 - 115.19 mm (4.515 - 4.535 in.)
Exhaust: 116.94 - 117.44 mm (4.603 - 4.623 in.)
Stem Diameter
Intake: 5.934 - 5.952 mm (0.2337 - 0.2344 in.)
Exhaust: 5.906 - 5.924 mm (0.2326 - 0.2333 in.)
Valve Margin
Intake: 1.15 - 1.48 mm (0.0452 - 0.0582 in.)
Exhaust: 1.475 - 1.805 mm (0.0580 - 0.0710 in.)
Fig. 91 Valve Seat Refacing
Fig. 92 Spring Installed Height and Valve Tip to
Spring Seat Dimensions
NS/GSENGINE 9 - 31
DISASSEMBLY AND ASSEMBLY (Continued)

(4) If inner rotor measures 7.64 mm (.301 inch) or
less replace inner rotor (Fig. 97).
(5) Slide outer rotor into pump housing, press to
one side with fingers and measure clearance between
rotor and housing (Fig. 98). If measurement is 0.39
mm (0.015 inch.) or more, replace housing only if
outer rotor is in specification.
(6) Install inner rotor into pump housing. If clear-
ance between inner and outer rotors (Fig. 99) is .203
mm (.008 inch) or more, replace both rotors.
(7) Place a straightedge across the face of the
pump housing, between bolt holes. If a feeler gauge
of .102 mm (.004 inch) or more can be inserted
between rotors and the straightedge, replace pump
assembly (Fig. 100).ONLYif rotors are in specs.
(8) 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.
(9) The relief valve spring has a free length of
approximately 60.7 mm (2.39 inches) it should test
between 18 and 19 pounds when compressed to 40.5
mm (1.60 inches). Replace spring that fails to meet
specifications.(10) If oil pressure is low and pump is within spec-
ifications, inspect for worn engine bearings, damaged
or missing oil pick-up tube o-ring, clogged oil pick-up
tube screen, clogged oil filter and stuck open pres-
sure relief valve or other reasons for oil pressure
loss.
Fig. 96 Measuring Outer Rotor Thickness
Fig. 97 Measuring Inner Rotor Thickness
Fig. 98 Measuring Outer Rotor Clearance in
Housing
Fig. 99 Measuring Clearance Between Rotors
Fig. 100 Measuring Clearance Over Rotors
NS/GSENGINE 9 - 33
CLEANING AND INSPECTION (Continued)