spark plugs CHEVROLET DYNASTY 1993 Owner's Manual

The MOPAR Silicone Rubber Adhesive Sealant
gasket material or equivalent should be applied in a
continuous bead approximately 3mm (0.120 inch) in
diameter. All mounting holes must be circled. For
corner sealing, a 3.17 or 6.35 mm (1/8 or 1/4 inch.)
drop is placed in the center of the gasket contact
area. Uncured sealant may be removed with a shop
towels. Components should be torqued in place while
the sealant is still wet to the touch (within 10 min-
utes). The usage of a locating dowel is recommended
during assembly to prevent smearing of material off
location.
CRANKSHAFT SPROCKET BOLT ACCESS PLUG
An Access plug is located in the right inner fender
shield. Remove the plug and insert proper size
socket, extension and rachet, when crankshaft rota-
tion is necessary.
ENGINE PERFORMANCE
If a loss of performance is noticed, ignition timing
should be checked. If ignition timing is retarded by
9, 18 or 27É indicating 1, 2 or 3 (timing belt or chain)
teeth may have skipped, then, camshaft and acces-
sory shaft timing with the crankshaft should be
checked. Refer to Engine Timing Sprockets and Oil
Seals of the Engine Section. To provide best vehicle performance and lowest ve-
hicle emissions, it is most important that the tune-up
be done accurately. Use the specifications listed on
the Vehicle Emission Control Information label
found in the engine compartment. (1) Test cranking amperage draw. See Starting
Motor Cranking Amperage Draw Electrical Section
of this manual. (2) Tighten the intake manifold bolts to specifica-
tions. (3) Perform cylinder compression test.(a) Check engine oil level and add oil if neces-
sary. (b) Drive the vehicle until engine reaches normal
operating temperature. (c) Select a route free from traffic and other
forms of congestion, observe all traffic laws, and ac-
celerate through the gears several times briskly.
CAUTION: Do not overspeed the engine. The higher
engine speed may help clean out valve seat deposits
which can prevent accurate compression readings.
(d) Remove all spark plugs from engine. As
spark plugs are being removed, check electrodes for
abnormal firing indicators fouled, hot, oily, etc.
Record cylinder number of spark plug for future
reference. (e) Disconnect coil wire from distributor and se-
cure to good ground to prevent a spark from start- ing a fire (Conventional Ignition System). For Direct
Ignition System DIS disconnect the coil connector. (f) Be sure throttle blade is fully open during the
compression check. (g) Insert compression gage adaptor into the #1
spark plug hole in cylinder head. Crank engine until
maximum pressure is reached on gage. Record this
pressure as #1 cylinder pressure. (h) Repeat Step G for all remaining cylinders.
(i) Compression should not be less than (689kPa)
100 psi and not vary more than 25 percent from
cylinder to cylinder. (j) If one or more cylinders have abnormally low
compression pressures, repeat steps 3b through 3h. (k) If the same cylinder or cylinders repeat an
abnormally low reading on the second compression
test, it could indicate the existence of a problem in
the cylinder in question.
The recommended compression pressures are
to be used only as a guide to diagnosing engine
problems. An engine should not be disassembled
to determine the cause of low compression un-
less some malfunction is present. (4) Clean or replace spark plugs as necessary and
adjust gap as specified in Electrical Group 8. Tighten to
specifications. (5) Test resistance of spark plug cables. Refer to
Ignition System Secondary Circuit Inspection Electri-
cal Section Group 8. (6) Inspect the primary wire. Test coil output volt-
age, primary and secondary resistance. Replace parts
as necessary. Refer to Ignition System and make nec-
essary adjustment. (7) Ignition timing should be set to specifications.
(See Specification Label in engine compartment). (8) Test fuel pump for pressure and vacuum. Refer to
Fuel System Group 14, Specifications. (9) The air filter elements should be replaced as
specified in Lubrication and Maintenance, Group 0. (10) Inspect crankcase ventilation system as out
lined in Lubrication and Maintenance, Group 0. For
emission controls see Emission Controls Group 25 for
service procedures. (11) Inspect and adjust accessory belt drives refer-
ring to Accessory Belt Drive in Cooling System, Group
7 for proper adjustments. (12) Road test vehicle as a final test.
HONING CYLINDER BORES
Before honing, stuff plenty of clean shop towels
under the bores, over the crankshaft to keep abrasive
materials from entering crankcase area. (1) Used carefully, the cylinder bore resizing hone
C-823 equipped with 220 grit stones, is the best tool for
this job. In addition to deglazing, it will reduce taper
and out-of-round as well as removing light
9 - 2 ENGINE Ä

CAUTION: Be sure that the tapped holes maintain
the original centerline.
Heli-Coil tools and inserts are readily available
from automotive parts jobbers.
HYDROSTATIC LOCKED ENGINE
When an engine is suspected to be hydrostaticly
locked, regardless of what caused the problem, these
steps should be used.
CAUTION: Do Not Use Starter Motor To Rotate En-
gine, severe damage may occur.
(1) Inspect air cleaner, induction system and in-
take manifold to insure system is dry and clear of
foreign material. (2) Remove negative battery cable.
(3) Place a shop towel around the spark plugs
when removing them from the engine. This will
catch any fluid that may possibly be in the cylinder
under pressure. (4) With all spark plugs removed, rotate engine
crankshaft using a breaker bar and socket. (5) Identify the fluid in the cylinder(s) (i.e., cool-
ant, fuel, oil or other). (6) Make sure all fluid has been removed from the
cylinders. Inspect engine for damage (i.e., Connecting
Rods, Pistons, Valves etc.) (7) Repair engine or components as necessary to
prevent this problem from occurring again.
CAUTION: Squirt approximately 1 teaspoon of oil
into cylinders, rotate engine to lubricate the cylin-
der walls to prevent damage on restart.
(8) Install new spark plugs.
(9) Drain engine oil and remove oil filter.
(10) Fill engine with specified amount of approved
oil and install new oil filter. (11) Connect negative battery cable.
(12) Start engine and check for any leaks.
Ä ENGINE 9 - 5

(4) Hold engine sprocket with Special Tool C-4687
(with adaptor Tool C-4687-1) while removing/install-
ing screw (Fig. 8). The 2.5L Engine camshaft/inter-
mediate shaft sprockets have an off-set hub and are
identified with a six-hole pattern .
(5) Remove crankshaft seal using Special Tool
6341. Remove intermediate and camshaft seals using
Special Tool C-4679 (Fig. 10).
CAUTION: Do not nick shaft seal surface or seal
bore.
(6) Shaft seal lip surface must be free of varnish,
dirt or nicks. Polish with 400 grit paper if necessary. (7) Install engine crankshaft seal into retainer us-
ing Special Tool 6342 and 6343. Install Intermediate and Camshaft seals using Special Tool C-4680. In-
stall seals until flush (Fig. 10).
CAMSHAFT, CRANKSHAFT AND INTERMEDIATE
SHAFTS TIMING PROCEDURE
(1) Remove all spark plugs. Turn crankshaft and
intermediate shaft until markings on sprockets are
in line, see arrows (Fig. 11 ).
Fig. 9 Removing Crankshaft, Intermediate Shaft and Camshaft Oil Seal
Fig. 8 Removing/Installing Camshaft or IntermediateShaft Sprocket Screw
Fig. 10 Installing Crankshaft,Intermediate Shaft, and Camshaft Seal
Fig. 11 Crankshaft and Intermediate Shaft Timing
9 - 20 2.2/2.5L ENGINE Ä

(2) Turn camshaft until arrows on hub are inline
with No. 1 camshaft cap to cylinder headline. Small
hole (arrow Fig. 12) must be in vertical center line. (3) Install timing belt.
(4) Rotate crankshaft two full revolutions and re-
check timing.
CAUTION: Do not allow oil or solvents to contact
the timing belt as they can deteriorate the rubber
and cause tooth skipping.
(5) Rotate crankshaft till number 1 cylinder is at
the TDC position. (6) Put belt tension Special Tool C-4703 horizon-
tally on large hex of timing belt tensioner pulley and
loosen tensioner lock nut. (7) Reset belt tension Special Tool C-4703 index if
necessary to have axis within 15É of horizontal. (Fig.
13) (8) Turn engine clockwise from TDC two crank revo-
lutions to TDC. Do not reverse rotate crankshaft
or attempt to rotate engine using cam or acces-
sory shaft attaching screw. (9) Hold weighted wrench in position while tighten-
ing bolt on tensioner to 61 N Im (45 ft. lbs.) torque.
(10) Lower engine onto engine mount install mount-
ing bolts and tighten to specifications refer to (Fig. 3). (11) Remove jack from under engine.
(12) Inspect foam stuffer block condition and posi-
tion (Fig. 14). Stuffer block should be intact and secure
within the engine bracket tunnel. (13) Position both halves of timing belt cover to-
gether (Fig. 4). (14) Install fasteners holding cover to cylinder head
and block. Tighten fasteners to 4 N Im (40 in. lbs.)
torque. (15) Valve Timing Check; (timing belt cover in-
stalled). With number one cylinder at TDC, small hole
in sprocket must be centered in timing belt cover hole
(Fig. 12). If hole is not aligned correctly perform
procedure again. (16) Install spark plugs.
Fig. 12 Camshaft Timing
Fig. 13 Adjusting Drive Belt Tension
Fig. 14 Foam Stuffer Block Location
Ä 2.2/2.5L ENGINE 9 - 21

CAMSHAFT AND CRANKSHAFT TIMING
PROCEDURE
INSTALLATION
(1) Remove air cleaner fresh air duct.
(2) Remove ignition cable cover (Fig. 7).
(3) Remove valve covers and loosen rocker arm as-
semblies about 3 turns as shown in (Fig. 8).
CAUTION: Check lash adjuster for loose or missing
retainers before continuing service procedure.
(4) Align and pin both intake and exhaust cam
sprockets with 3/32 drills or pin punches (Fig. 9). Ac-
cessory Shaft does not need to be timed. (5) Remove spark plugs.
(6) Install a dial indicator in Number 1 spark plug
hole (Fig. 10). (7) Rotate crankshaft till number 1 piston is at
Top Dead Center. Mark the engine block for TDC
reference. (8) Install timing belt and idler pulley in sequence
shown in (Fig. 11). (9) Remove dial indicator from cylinder head (Fig.
10). Remove drills or pins from camshaft sprockets
(Fig. 11). (10) Adjust tension to 445 N (110 lbs.)
New beltor
311 N (70 lbs.) Used belt. Install belt tension gauge on
timing belt (Fig. 12) adjust tensioner until specified
tension is achieved.
CAUTION: Belt tension gauge must be installed be-
tween the belt teeth to get a accurate reading .
(11) Rotate crankshaft clockwise 2 full revolutions
and check alignment of camshaft and crankshaft tim-
ing marks. Do not reverse rotate crankshaft or
attempt to rotate engine using cam or accessory
shaft attaching screw.
CAUTION: Do not allow oil or solvents to contact the
timing belt as they can deteriorate the rubber and
cause tooth skipping.
Fig. 7 Ignition Cable Cover
Fig. 8 Rocker Arm Shaft Assemblies
Fig. 9 Camshafts Pinned Into Position
Fig. 10 Dial Indicator Located in Number 1 Cylinder
9 - 34 2.2/2.5L ENGINE Ä

(12) Recheck belt tension, adjust if necessary.
(13) Torque rocker arm shafts in sequence shown
(Fig. 13) to 12 N Im (105 in. lbs.) then to 24 N Im (210
in. lbs.). (14) Install valve covers, spark plugs, ignition cables
and ignition cable cover. (15) Install air cleaner fresh air duct.
(16) Raise vehicle. Install lower timing belt cover
and accessory drive belt tensioner pulley. Refer to
procedure in this section. (17) Lower vehicle. Install right engine mount (Fig.
5). (18) Inspect foam stuffer block condition and posi-
tion (Fig. 14). Stuffer block should be intact and secure
within the engine bracket tunnel. (19) Install upper timing belt cover and PCV tube.
Refer to procedure in this section. (20) Install accessory drive belt. Refer to procedure
in this section.
SERVICING OIL SEALS
Refer to servicing oil seals in this group for proce-
dures. To service the intake cam seal (Turbo III) the
right engine mount must be removed. Refer to
engine mount removal of this Group.
Fig. 13 Rocker Arm ShaftÐInstallation
Fig. 14 Foam Stuffer Block Location
Fig. 11 Camshafts and Crankshaft Timing Marks
Fig. 12 Belt Tension Gauge Location
Ä 2.2/2.5L ENGINE 9 - 35

(15) Install hood.
(16) Connect battery.
(17) Start engine and run until operating temper-
ature is reached. (18) Adjust transmission or linkage if necessary.
ROCKER ARMS AND SHAFT ASSEMBLY
REMOVAL
(1) Remove upper intake manifold assembly. Refer
to Intake and Exhaust Manifolds, Group 11. (2) Disconnect spark plug wires by pulling on the
boot straight out in line with plug. (3) Disconnect closed ventilation system and evap-
oration control system from cylinder head cover. (4) Remove cylinder head cover and gasket.
(5) Remove four rocker shaft bolts and retainers.
(6) Remove rocker arms and shaft assembly.
(7) If rocker arm assemblies are disassembled for
cleaning or replacement. Assemble rocker arms in
their original position.Refer to (Fig. 5) for rocker arm
for positioning on the shaft.
INSTALLATION
(1) Install rocker arm and shaft assemblies with
the stamped steel retainers in the four positions,
tighten to 28 N Im (250 in. lbs.) (Fig. 5).
WARNING: THE ROCKER ARM SHAFT
SHOULD BE TORQUED DOWN SLOWLY,
STARTING WITH THE CENTERMOST BOLTS.
ALLOW 20 MINUTES TAPPET BLEED DOWN
TIME AFTER INSTALLATION OF THE
ROCKER SHAFTS BEFORE ENGINE OPERA-
TION. (2) Clean cylinder head cover gasket surface. In-
spect cover for distortion and straighten if necessary. (3) Clean head rail if necessary. Install a new gas-
ket and tighten cylinder head cover fasteners to 12
N Im (105 in. lbs.).
(4) Install closed crankcase ventilation system and
evaporation control system. (5) Install spark plug wires.
(6) Install upper intake manifold assembly. Refer to
Exhaust Systems and Intake Manifolds Group 11.
CYLINDER HEADS
The alloy aluminum cylinder heads shown in (Fig. 6)
are held in place by 9 bolts. The spark plugs are located
in peak of the wedge between the valves.
REMOVAL
(1) Drain cooling system refer to Cooling System
Group 7 for procedure and disconnect negative battery
cable. Remove intake manifold, and throttle body. Refer to
Group 11 Exhaust System and Intake Manifold. (2) Disconnect coil wires, sending unit wire, heater
hoses and by-pass hose. (3) Remove closed ventilation system, evaporation
control system and cylinder head covers. (4) Remove exhaust manifolds.
(5) Remove rocker arm and shaft assemblies. Re-
move push rods and identify to insure installation
in original locations. (6) Remove the 9 head bolts from each cylinder head
and remove cylinder heads (Fig. 7).
Fig. 5 Rocker Arm Location Left Blank
Fig. 6 Cylinder Head Assembly
Fig. 7 Cylinder Head Bolts Location
9 - 102 3.3/3.8L ENGINE Ä

(8) Place new cylinder head cover gaskets in position
and install cylinder head covers. Tighten to 12 N Im
(105 in. lbs.).
INTAKE MANIFOLD SEALING
The intake manifold gasket is a one-piece stamped
steel gasket with a sealer applied from the manufac-
turer. This gasket has end seals incorporated with it. WARNING: INTAKE MANIFOLD GASKET IS
MADE OF VERY THIN METAL AND MAY CAUSE
PERSONAL INJURY, HANDLE WITH CARE. (1) Clean all surfaces of cylinder block and cylinder
heads. (2) Place a drop ( about 1/4 in. diameter) of Mopar
Silicone Rubber Adhesive Sealant or equivalent, onto
each of the fourmanifold to cylinder head gasket
corners (Fig. 13).
(3) Carefully install the intake manifold gasket (Fig.
14). Torque end seal retainer screws to 12 N Im (105 in.
lbs.). (4) Install intake manifold and (8) bolts and torque
to1N Im (10 in. lbs.). Then tighten bolts to 22 N Im
(200 in. lbs.) in sequence shown in (Fig. 15). Then
tighten again to 22 N Im (200 in. lbs.). After intake
manifold is in place, inspect to make sure seals are in place.
Refer to Group 11 Exhaust System and
Intake Manifold to complete Intake Manifold Assem-
bly. (5) Install exhaust manifolds and tighten bolts to
27 N Im (20 ft. lb.) and nuts to 20 N Im (15 ft. lbs.).
(6) Adjust spark plugs to specification in Electrical
Section, Group 8, and install the plugs.
VALVE SERVICE
VALVES AND VALVE SPRINGS
The valves are arranged in line in the cylinder
heads and inclined 18 degrees. The rocker shaft sup-
port are cast integral with the heads.
REMOVAL
(1) With cylinder head removed, compress valve
springs using Valve Spring Compressor Tool
C-3422-B with adapter 6412 as shown in (Fig. 16). (2) Remove valve retaining locks, valve spring re-
tainers, valve stem seals and valve springs.
Fig. 14 Intake Manifold Gasket Retainers
Fig. 15 Intake Manifold Removal and Installation
Fig. 12 Rocker Arm Shaft Retainers
Fig. 13 Intake Manifold Gasket Sealing
9 - 104 3.3/3.8L ENGINE Ä

length of the spring to be tested is 33.34mm (1-5/16
inches). Turn table of Tool C-647 until surface is in line
with the 33.34mm (1-5/16 inch) mark on the threaded
stud and the zero mark on the front. 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 two. 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.
VALVE INSTALLATION
(1) Coat valve stems with clean engine oil and insert
them in cylinder head. (2) Check valve tip to spring seat dimension A after
grinding the valve seats or faces. Grind valve tip to give
49.541 to 51.271 mm (1.950 to 2.018 inch.) over spring
seat when installed in the head (Fig. 17). Check valve
tip for scoring, if necessary, the tip chamfer should be
reground to prevent seal damage when the valve is
installed. (3) Install new cup seals on all valve stems and over
valve guides (Fig. 24). Install valve springs and valve
retainers.
(4) Compress valve springs with Valve Spring Com-
pressor Tool C-3422-B, with adapter 6412 install locks
and release tool. If valves and/or seats are re-
ground, measure the installed height of springs
dimension B, make sure measurements is taken
from top of spring seat to the bottom surface of
spring retainer. If height is greater than 1-19/32
inches, (40.6mm), install a 1/32 inch (.794mm)
spacer in head counterbore to bring spring
height back to normal 1-17/32 to 1-19/32 inch (39.1
to 40.6mm) .
REPLACE VALVE STEM SEALS OR VALVE
SPRINGS, CYLINDER HEAD NOT REMOVED
(1) Perform fuel system pressure release procedure
before attempting any repairs (2) Disconnect negative battery cable. (3) Remove Air Cleaner Cover and hose assembly.
(4) Remove Intake Manifold; Refer to
Intake/Exhaust Manifold 3.3/3.8L Engine Group 11
Exhaust System and Intake Manifolds of this manual
for removal procedure. (5) Remove cylinder head covers and spark plugs.
(6) Remove connector wire from ignition coils.
(7) Using suitable socket and flex handle at crank-
shaft pulley retaining screw, turn engine so the num-
ber 1 piston is at Top Dead Center on the compression
stroke. (8) Remove rocker arms with rocker shaft and in-
stall a dummy shaft. The rocker arms should not be
disturbed and left on shaft. (9) With air hose attached to spark plug adapter
installed in number 1 spark plug hole, apply 90 to 100
psi air pressure (620.5 to 689 kPa). This is to hold
valves into place while servicing components. (10) Using Tool C-4682 or Equivalent compress
valve spring and remove retainer valve locks and valve
spring. (11) The intake valve stem seals should be pushed
firmly and squarely over the valve guide using the
valve stem as guide. Do Not Forceseal against top of
guide. When installing the valve retainer locks, com-
press the spring only enoughto install the locks.
CAUTION:Do not pinch seal between retainer and top
of valve guide .
(12) Follow the same procedure on the remaining 5
cylinders using the firing sequence 1-2-3-4-5-6. Make
sure piston in cylinder is at TDC on the valve
spring that is being covered. (13) Remove spark plug adapter tool .
(14) Remove dummy shaft and install rocker shaft
assembly and tighten screws to 28 N Im (250 in. lbs.).
Fig. 24 Checking Valve Installed Height
Fig. 25 Installing Valve, Cup Seal, Spring and Re-
tainer
Ä 3.3/3.8L ENGINE 9 - 107

(2) Clean varnish deposits from inside of tappet
body above plunger cap. (3) Invert tappet body and remove plunger cap,
plunger, flat or ball check valve, check valve spring,
check valve retainer and plunger spring. Check valve
could be flat or ball.
CLEANING AND ASSEMBLY
(1) Clean all tappet parts in a solvent that will re-
move all varnish and carbon. (2) Replace tappets that are unfit for further ser-
vice with new assemblies. (3) If plunger shows signs of scoring or wear, valve
is pitted, or valve seat on end of plunger indicates
any condition that would prevent valve from seating,
install a new tappet assembly. (4) Assemble tappets (Fig. 27).
INSTALLATION
(1) Lubricate tappets.
(2) Install tappets in their original positions.
(3) With roller tappets, install aligning yokes with
(Fig. 26). (4) Install yoke retainer and torque screws to 12
N Im (105 in. lbs.) (Fig. 26).
(5) Install cylinder heads. Refer to cylinder head
installation of this section for procedure. (6) 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 hy-
draulic tappets have filled with oil and have become
quiet.
VALVE TIMING
(1) Remove front valve cover and all 6 spark plugs.
(2) Rotate engine until the #2 piston is at TDC of
the compression stroke. (3) Install a degree wheel on the crankshaft pulley.
(4) With proper adaptor, install a dial into #2
spark plug hole. Using the indicator find TDC on the
compression stroke. (5) Position the degree wheel to zero.
(6) Remove dial indicator from spark plug hole. (7) Place a 5.08mm (.200 inch) spacer between the
valve stem tip of #2 intake valve and rocker arm
pad. Allow tappet to bleed down to give a solid tap-
pet effect. (8) Install a dial indicator so plunger contacts the
#2 intake valve spring retainer as nearly perpendic-
ular as possible. Zero the indicator. (9) Rotate the engine clockwise until the in take
valve has lifted .254mm (0.010 inch).
CAUTION: Do not turn crankshaft any further clock-
wise as intake valve might bottom and result in se-
rious damage.
(10) Degree wheel should read 3 degrees BTDC to
4 degrees ATDC.
TIMING CHAIN COVER, OIL SEAL AND CHAIN
COVER
REMOVAL
(1) Disconnect battery.
(2) Drain cooling system. Refer to Cooling System
Group 7 for procedure. (3) Support engine and remove right engine
mount. (4) Raise vehicle on hoist. Drain engine oil.
(5) Remove oil pan and oil pump pick-up. It may
necessary to remove transmission inspection cover. (6) Remove right wheel and inner splash shield.
(7) Remove drive belt. Refer to Cooling System
Group 7 for procedure. (8) Remove A/C compressor and set aside.
(9) Remove A/C compressor mounting bracket.
(10) Remove crankshaft pulley (Fig. 1).
(11) Remove idler pulley from engine bracket.
(12) Remove engine bracket (Fig. 2).
(13) Remove cam sensor from chain case cover
(Fig. 3).
Fig. 27 Hydraulic Roller Tappet Assembly
Fig. 1 Removing Crankshaft Pulley
Ä 3.3/3.8L ENGINE 9 - 109