Chrysler Le Baron, Dodge Dynasty, Plymouth Acclaim. Manual — part 566

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 27° 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

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ENGINE

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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 intersect at 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 bearings can

only be determined by removing the weight of the
crankshaft. This can be accomplished by either of
two methods:

PREFERRED METHOD — 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.)
• When checking #1 main brg shim #2 main brg

• When checking #2 main brg shim #1 & 3 main brg

• When checking #3 main brg shim #2 & 4 main brg

• When checking #4 main brg shim #3 & 5 main brg

• When 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

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ENGINE

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REMOVE ALL SHIMS BEFORE REASSEM-

BLING ENGINE

ALTERNATIVE METHOD — 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.

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ENGINE

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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.

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ENGINE

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