CHEVROLET DYNASTY 1993 Service Manual

ENGINE
CONTENTS
page page
2.2/2.5L ENGINES ....................... 8
3.0L ENGINE .......................... 66 3.3/3.8L ENGINE
....................... 98
STANDARD SERVICE PROCEDURES ......... 1
STANDARD SERVICE PROCEDURES INDEX
page page
Crankshaft Sprocket Bolt Access Plug .......... 2
Engine Performance ....................... 2
Form-In-Place Gaskets ..................... 1
Honing Cylinder Bores ..................... 2
Hydrostatic Locked Engine .................. 5 Lash Adjuster (Tappet) Noise Diagnosis
........ 4
Measuring Main Bearing Clearance and Connecting Rod Bearing Clearance ................... 3
Repair of Damaged or Worn Threads .......... 4
FORM-IN-PLACE GASKETS
There are numerous places where form-in-place
gaskets are used on the engine. Care must be taken
when applying form-in-place gaskets to assure ob-
taining the desired results. Bead size, continuity, and
location are of great importance. Too thin a bead can
result in leakage while too much can result in spill-
over which can break off and obstruct fluid feed
lines. A continuous bead of the proper width is essen-
tial to obtain a leak-free joint. Two types of form-in-place gasket materials are
used in the engine area. Mopar Silicone Rubber Ad-
hesive Sealant and anaerobic gasket materials, each
have different properties and cannot be used inter-
changeably.
MOPAR SILICONE RUBBER ADHESIVE SEALANT
Mopar Silicone Rubber Adhesive Sealant or equiv-
alent, normally black in color, is available in three
ounce tubes. Moisture in the air causes the Mopar
Silicone Rubber Adhesive Sealant material to cure.
This material is normally used on flexible metal
flanges. It has a shelf life of one year and will not
properly cure if over age. Always inspect the package
for the expiration date before use.
MOPAR GASKET MAKER
MOPAR Gasket Maker is an anaerobic type gasket
material normally red in color. The material cures in
the absence of air when squeezed between two metal-
lic surfaces. It will not cure if left in the uncovered tube. It is normally red in color. The anaerobic ma-
terial is for use between two machined surfaces. Do
not used on flexible metal flanges.
GASKET DISASSEMBLY
Parts assembled with form-in-place gaskets may be
disassembled without unusual effort. In some in-
stances, it may be necessary to lightly tap the part
with a mallet or other suitable tool to break the seal
between the mating surfaces. A flat gasket scraper
may also be lightly tapped into the joint but care
must be taken not to damage the mating surfaces.
SURFACE PREPARATION
Scrape clean or wire brush all gasket surfaces re-
moving all loose material. Inspect stamped parts to
assure gasket rails are flat. Flatten rails with a ham-
mer on a flat plate if required. Gasket surfaces must
be free of oil and dirt. Make sure old gasket material
is removed from blind attaching holes.
FORM-IN-PLACE GASKET APPLICATION
Assembling parts using a form-in-place gasket re-
quires care but it's easier then using precut gaskets. MOPAR Gasket Maker material should be applied
sparingly 1mm(0.040 inch.) diameter or less of seal-
ant to one gasket surface. Be certain the material
surrounds each mounting hole. Excess material can
easily be wiped off. Components should be torqued in
place within 15 minutes. The use of a locating dowel
is recommended during assembly to prevent smear-
ing the material off location.
Ä ENGINE 9 - 1

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

scuffing, scoring or scratches. Usually a few strokes
will clean up a bore and maintain the required limits.(2) Deglazing of the cylinder walls may be done
using a cylinder surfacing hone, Tool C-3501, equipped
with 280 grit stones (C-3501-3810) if the cylinder bore
is straight and round. 20-60 strokes depending on the
bore condition will be sufficient to provide a satisfac-
tory surface. Inspect cylinder walls after each 20
strokes. Using a light honing oil available from major
oil distributors. Do not use engine or transmission
oil, mineral spirits or kerosene. (3) Honing should be done by moving the hone up
and down fast enough to get a cross-hatch pattern.
When hone marks intersectat 50-60 degrees, the
cross hatch angle is most satisfactory for proper seat-
ing of rings (Fig. 1).
(4) A controlled hone motor speed between 200-300
RPM is necessary to obtain the proper cross-hatch
angle. The number of up and down strokes per minute
can be regulated to get the desired 50-60 degree angle.
Faster up and down strokes increase the cross-hatch
angle. (5) After honing, it is necessary that the block be
cleaned again to remove all traces of abrasive.
CAUTION: Be sure all abrasive are removed from
engine parts after honing. It is recommended that a
solution of soap and hot water be used with a brush
and the parts then thoroughly dried. The bore can be
considered clean when it can be wiped clean with a
white cloth and cloth remains clean. Oil the bores
after cleaning to prevent rusting.
MEASURING MAIN BEARING CLEARANCE AND
CONNECTING ROD BEARING CLEARANCE
PLASTIGAGE METHOD
Engine crankshaft bearing clearances can be deter-
mined by use of Plastigage or equivalent. The follow-
ing is the recommended procedure for the use of
Plastigage: (1) Remove oil film from surface to be checked.
Plastigage is soluble in oil. (2) The total clearance of the main bearingscan
only be determined by removing the weight of the
crankshaft. This can be accomplished by either of
two methods: PREFERRED METHOD Ð Shimming the bear-
ings adjacent to the bearing to be checked in order to
remove the clearance between upper bearing shell
and the crankshaft. This can be accomplished by
placing a minimum of 0.254mm (.010 inch) shim (e.
g. cardboard, matchbook cover, etc.) between the
bearing shell and the bearing cap on the adjacent
bearings and snugging bolts to 14-20 N Im (10-15
ft.lb.)
² When checking #1 main brg shim #2 main brg
²
When checking #2 main brg shim # 1 & 3 main brg
²When checking #3 main brg shim #2 & 4 main brg
²When checking #4 main brg shim #3 & 5 main brg
²When checking #5 main brg shim #4 main brg
Fig. 2 Plastigage Placed in Lower Shell
Fig. 3 Clearance Measurement
Fig. 1 Cylinder Bore Cross-Hatch Pattern
Ä ENGINE 9 - 3

REMOVE ALL SHIMS BEFORE REASSEM-
BLING ENGINE ALTERNATIVE METHOD Ð With the weight of
the crankshaft being supported by a jack under the
counterweight adjacent to the bearing being checked. (3) Place a piece of Plastigage across the entire
width of the bearing shell in the cap approximately
6.35 mm (1/4 inch) off center and away from the oil
holes (Fig. 2). (In addition, suspect areas can be
checked by placing the Plastigage in the suspect area).
Torque the bearing cap bolts of the bearing being
checked to the proper specifications. (4) Remove the bearing cap and compare the width
of the flattened Plastigage (Fig. 3) with the metric scale
provided on the package. Locate the band closest to the
same width. This band shows the amount of clearance
in thousandths of a millimeter. Differences in readings
between the ends indicate the amount of taper present.
Record all readings taken. Refer to Engine Specifica-
tions. Plastic-Gage generally is accompanied by
two scales. One scale is in inches, the other is a
metric scale. (5) Plastigage is available in a variety of clearance
ranges. The 0.025-0.076mm (.001-.003 inch) is usually
the most appropriate for checking engine bearing
proper specifications.
CONNECTING ROD BEARING CLEARANCE
Engine crankshaft bearing clearances can be deter-
mined by use of Plastigage or equivalent. The following
is the recommended procedure for the use of Plasti-
gage: (1) Rotate the crankshaft until the connecting rod to
be checked is at the bottom of its stroke. (2) Remove oil film from surface to be checked.
Plastigage is soluble in oil. (3) Place a piece of Plastigage across the entire
width of the bearing shell in the bearing cap approxi-
mately 6.35 mm (1/4 inch.) off center and away from
the oil hole (Fig. 2). In addition, suspect areas can be
checked by placing plastigage in the suspect area. (4) Before assembling the rod cap with Plastigage in
place, the crankshaft must be rotated until the con-
necting being checked starts moving toward the top of
the engine. Only then should the cap be assembled and
torqued to specifications. Do not rotate the crank-
shaft while assembling the cap or the Plastigage
may be smeared, giving inaccurate results. (5) Remove the bearing cap and compare the width
of the flattened Plastigage (Fig. 3) with the metric
scale provided on the package. Locate the band closest
to the same width. This band shows the amount
of clearance in thousandths of a millimeter. Differences
in readings between the ends indicate the amount
of taper present. Record all readings taken.
Refer to Engine Specifications. Plastigage generally is accompanied by two scales. One scale is in
inches, the other is a metric scale. (6) Plastigage is available in a variety of clearance
ranges. The 0.025-0.076mm (.001-.003 inch) is usually
the most appropriate for checking engine bearing
proper specifications.
LASH ADJUSTER (TAPPET) NOISE DIAGNOSIS
A tappet-like noise may be produced from several
items. Check the following items. (1) Engine oil level too high or too low. This may
cause aerated oil to enter the adjusters and cause them
to be spongy. (2) Insufficient running time after rebuilding cylin-
der head. Low speed running up to 1 hour may be
required. During this time, turn engine off and let set for a few
minutes before restarting. Repeat this several times
after engine has reached normal operating tempera-
ture. (3) Low oil pressure.
(4) The oil restrictor pressed into the vertical oil
passage to the cylinder head of Balance Shaft Engines
Only is plugged with debris. (5) Air ingested into oil due to broken or cracked oil
pump pick up. (6) Worn valve guides.
(7) Rocker arm ears contacting valve spring retainer
(2.2/2.5L engines). (8) Rocker arm loose, adjuster or tappet stuck or at
maximum extension and still leaves lash in the system. (9) Faulty lash adjuster or tappet.(a) Check for sponginess while still installed in
engine. Depress part of rocker arm just over adjuster
or pushrod . Normal adjusters should feel very firm.
Spongy adjusters can be depressed to the bottomed
position easily. (b) Remove suspected lash adjuster or tappet, pry
off retainer cap or snap ring and disassemble. Do
not reuse retainer caps . Do not interchange parts
and make sure that care and cleanliness is exercised
in the handling of parts. (c) Clean out dirt and varnish with solvent.
(d) Reassemble with engine oil.
(e) Check for sponginess.
(f) If still spongy, replace with new adjuster.
REPAIR OF DAMAGED OR WORN THREADS
Damaged or worn threads (including aluminum head
spark plug threads) can be repaired. Essentially, this
repair consists of drilling out worn or damaged
threads, tapping the hole with a special Heli-Coil (or
equivalent) Tap, and installing an insert into the
tapped hole. This brings the hole back to its original
thread size.
9 - 4 ENGINE Ä