oil filter DODGE TRUCK 1993 Service User Guide

0
- 24
LUBRICATION
AND
MAINTENANCE

•
CAUTION:
Do not
overfill
the
transmission.
(9) Adjust
the
level
of the ATF
accordingly.
It
is
important
to use the
correct fluid
in an

automatic transmission. MOPAR®ATF PLUS
(ATF Type
7176)
should
be
used. Dexron®
II

ATF
can be
used
if the
recommended fluid
is not
available,
(10) Insert
the
dipstick into
the
tube.

DRAIN, FILTER CHANGE, BAND ADJUSTMENT AND REFILL
The chart below lists
the
intervals
at
which
the

transmission should
be
serviced. Also, refer
to the

Fluid Capacities chart
for
fill capacity.
AUTOMATIC TRANSMISSION SERVICE
IN-
TERVALS

Normal

Usage
Light
Duty
Cycle

60 000
km
37,500
miles

Heavy
Duty
Cycle

38
000 km 24,000
miles

Severe
Usage
19 000 km 12,000
miles

J9100-19

It
is
very important
to use the
correct fluid
in

an automatic transmission. MOPAR®ATF PLUS
(ATF Type
7176)
should
be
used.
An
equivalent
Dexron®
II ATF
could
be
used only
if the
recom­
mended fluid
is not
available.
The torque converter does
not
have
a
drain plug.
No attempt should
be
made
to
drain
the
converter.
Refer
to
Group
21
—Transmissions
for
transmission
drain
and
refill procedures.

TRANSFER
CASE
(4WD
VEHICLES)
INSPECTION The NP205
and
NP241 transfer cases fluid level
should
be
checked whenever maintenance
is
neces­
sary under
the
vehicle.

FLUID
LEVEL
The vehicle must
be
level when
the
fluid level
is checked.
The transfer case drain fill hole plugs
are
located
at
the
rear
of the
housing (Figs.
4 and 5).

Determine
the
transfer case fluid level according
to

the following procedure.
(1) Raise
and
support
the
vehicle.
(2) Remove
the
fill hole plug (Figs.
4 and 5)
from
the transfer case.
The
fluid level should
be at the

bottom edge
of the
fill hole.
The
level
can be
slightly
below
the
bottom edge
of the
fill hole
if the
fluid
is
cold.
(3)
If the
level
is not
acceptable, raise
the
fluid
level
to the
bottom edge
of the
fill hole with: • MOPAR®ATF PLUS
or an
equivalent Dexron
II®

ATF
for
NP241 transfer case
• Multi-purpose gear
oil (API GL-5) or
engine
oil

(API
SG,
SG/CD
OR
SG/CE)
for
NP205 transfer

cases.

Add fluid
in
small amounts
to
raise
the
level. (4) Install
the
fill hole plug (Figs.
4 and 5).

Tighten
the
fill hole plug
to 27 N-m (20
ft-lbs) torque.
(5) Remove
the
support
and
lower
the
vehicle.

Fig.
4
HP241 Transfer
Case
Fig.
5
NP205 Transfer
Case

FLUID DRAIN
AND
REFILL The transfer case fluid should
be
changed every
60

000
km
(37,500 miles).
For
vehicles subject
to the

HEAVY DUTY CYCLE Maintenance Schedule,
a 58

000
km
(36,000 miles) interval
is
recommended.
(1) Raise
and
support
the
vehicle.
(2) Remove
the
fill hole plug (Figs.
4 and 5)
from
the transfer case. (3) Place
an
appropriate container under
the
trans­
fer case drain hole plug (Figs.
4 and 5).
(4) Remove
the
drain hole plug. Drain
the
fluid
from
the
transfer case into
the
container.

0
- 32
LUBRICATION
AND
MAINTENANCE

•

Fig.
5 Parking Brake Ratio Lever Lubrication (2) Note any indication of brake overheating,
wheel dragging or the vehicle pulling to one side.
(3) Evaluate any performance complaints received
from the owner/operator. (4) Repair the brake system as necessary (refer to
Group 5—Brakes for additional information and ser­
vice procedures).

BODY
COMPONENT
MECHANISMS
LUBRICATION REQUIREMENTS
All operating mechanisms and linkages should be
lubricated when necessary. This will maintain ease of operation and provide protection against rust and
excessive wear. The door weatherstrip seals should
be lubricated to prolong their life as well as to im­ prove door sealing.

LUBRICANT SPECIFICATIONS
All applicable exterior and interior vehicle operat­
ing mechanisms should be:
• Inspected • Cleaned
• All the pivoting/sliding contact areas on the mech­ anisms should then be lubricated.
MOPAR®Multi-Mileage Lubricant or an equiva­
lent, should be used to lubricate the mechanisms.
The door weatherstrip seals should be lubricated
with silicone lubricant spray. Refer to the Body Lu­
bricant Specifications chart below for additional lu­
bricant applications.

LUBRICATION
(1) When necessary, lubricate the cab and cargo
box operating mechanisms with the specified lubri­
cants.

(2) Apply silicone lubricant to a cloth and wipe it
on door seals to avoid over-spray that can soil pas­
senger clothing. (3) Before applying lubricant, the component
should be wiped clean. After lubrication, any excess
lubricant should be removed.
(4) The hood latch, latch release mechanism, latch
striker and safety latch should be lubricated periodi­
cally.
(5) The door lock cylinders should be lubricated 2
times each year (preferably autumn and spring): • Spray a small amount of lock cylinder lubricant di­
rectly into the lock cylinder
• Apply a small amount to the key and insert it into
the lock cylinder • Rotate it to the locked position and then back to
the unlocked position several times
• Remove the key. Wipe the lubricant from it with a
clean cloth to avoid soiling of clothing.

TIRES
RECOMMENDED MAINTENANCE
The condition of the tires should be inspected. The
inflation pressures tested/corrected at the same time as the engine oil is changed and the oil filter is re­
placed.
The tires/wheels should be rotated periodically to
ensure even tread wear. The tires/wheels should be
rotated at the first 12 000 km (7,500-miles) interval.
Thereafter, at each 24 000 km (15,000-miles) inter­
val.
INSPECTION
Inspect the tires for excessive wear, damage. Test
the tires for the recommended inflation pressure and adjust the pressure accordingly. Refer to the tire in­
flation pressure decal located on the left door face. Also to Group 22—Tires And Wheels for tire pres­sure charts, tire replacement, and treadwear indica­

tors.

ROTATION
Tires/wheels should be rotated according to the rec­
ommended interval. The first tire/wheel rotation is
the most important for establishing the prevention of uneven tread wear. After rotation, adjust the tire in­
flation pressure to the air pressure recommended on
the decal located on the left door face.
Refer to Group 22—Tires And Wheels for the rec­
ommended method of tire/wheel rotation.

HEADLAMPS

MAINTENANCE SCHEDULE
Every six months check the headlamp beams to en­
sure that the headlamp beams are correctly posi­
tioned.

AIM
ADJUSTMENT
Refer to Group 8L—Lamps for headlamp aim ad­
justment procedures.

•

COOLING
SYSTEM
7 - 35

HOSE
CLAMP TOOL
6094
HOSE

CLAMP

J9207-36
Fig.
48
Hose
damp Tool

TRANSMISSION
OIL
COOLER—EXCEPT DIESEL
The automatic transmission oil is cooled when it
passes through a cooler in the radiator lower tank (Fig. 49 and 50).

h*-TRANSMISSION

- OIL
COOLER

FRONT
OF
VEHICLE
AUTOMATIC

TRANSMISSION
PRESSURE
LINE
6 AND
8
CYLINDER ENGINE

RETURN
LINE
RY402

Fig.
49 Top View of
Transmission
Oil
Cooling
Circuit—Except Diesel—Typical

COOLING
TUBE (CUT-A-WAY)

DRAIN
COCK
HOSE

CLAMP
HOSE
TO

COOLER
LINE
HOSE
TO

COOLER
LINE

RY401

Fig.
50 Automatic
Transmission
Oil Cooler—Except
Diesel—
Typical

In case of a leak in the transmission oil cooler, en­
gine coolant may become mixed with transmission
fluid or transmission fluid may enter engine cooling system. Both cooling system and transmission should
be drained and inspected in the event cooler is leak­ ing.
REPLACING
OIL
COOLER
IN
BOTTOM
TANK

Remove radiator. Refer to Radiator removal in this
group. The servicing should be performed by a qual­
ified repair facility.
Once the repaired or replacement radiator has been
installed, fill the cooling system and inspect for

leaks.
Refer to Refilling Cooling System and Testing Cooling System For Leaks sections in this group. If
the transmission operates properly after repairing
the leak, drain the transmission and remove the
transmission oil pan. Inspect for sludge and/or rust. Inspect for a dirty or plugged inlet filter. If none of
these conditions are found, the transmission and
torque convertor may not require reconditioning. Re­
fer to Group 21 for automatic transmission servicing.

1RANSMISSI0N
OIL
COOLER-DIESEL
The transmission oil cooler is mounted to a bracket
on the turbocharger side of the engine (Fig. 51).

TRANSMISSION
OIL
COOLER
Fig.
51 Automatic
Transmission
Oil Cooler—5.9L

Diesel
REMOVAL

In case of a leak in the transmission oil cooler, en­
gine coolant may become mixed with transmission
fluid or transmission fluid may enter engine cooling system. Both cooling system and transmission should
be drained and inspected in the event cooler is leak­ ing. (1) Disconnect negative battery cable at battery.
(2) Drain cooling system. Refer to Draining Cool­
ing System. (3) Disconnect coolant lines from cooler.
(4) Disconnect transmission oil lines from cooler.
Plug cooler lines to prevent oil leakage. (5) Remove oil cooler mounting straps.
(6) Lift oil cooler off of mounting bracket.

INSTALLATION
(1) Position oil cooler on bracket.
(2) Install mounting straps.
(3) Connect transmission oil lines to cooler.

9
- 2
ENGINES

rial surrounds each mounting hole. Excess material
can easily be wiped off. Components should be
torqued in place within 15 minutes. The use of a lo­ cating dowel is recommended during assembly to pre­
vent smearing the material off location.

ENGINE PERFORMANCE
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 on the engine compartment hood.
(1) Test cranking amperage draw (refer to Group

8B,
Battery/Starter/Generator Service for the proper
procedures).
(2) Tighten the intake manifold bolts (refer to
Group 11, Exhaust System and Intake Manifold for
the proper specifications). (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
briskly accelerate through the gears several times. The higher engine speed may help clean out valve seat deposits which can prevent accurate compres­
sion readings.

CAUTION:
DO NOT
overspeed
the
engine.
(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.
(f) Be sure throttle blades are fully open during
the compression check. (g) Insert compression gage adaptor into the
No.l spark plug hole. Crank engine until maxi­
mum pressure is reached on gauge. Record this
pressure as No.l cylinder pressure.
(h) Repeat Step 3g for all remaining cylinders.
(i) Compression should not be less than 689 kPa
(100 psi) and not vary more than 172 kPa (25 psi)
from cylinder to cylinder.
(j) If cylinder(s) have abnormally low compres­
sion pressures, repeat steps 3a through 3h. (k) If the same cylinder(s) repeat an abnormally
low reading, it could indicate the existence of a
problem in the cylinder.
The recommended compression pressures are
to be used only as a guide to diagnosing engine
problems. An engine should NOT be disassem­ bled to determine the cause of low compression
unless some malfunction is present. (4) Clean or replace spark plugs as necessary. Ad­
just gap (refer to Group 8D, Ignition System for gap adjustment and torque).
(5) Test resistance of spark plug cables (refer to
Group 8D, Ignition System.
(6) Inspect the primary wire. Test coil output volt­

age,
primary and secondary resistance. Replace parts as necessary (refer to Group 8D, Ignition System and
make necessary adjustment).
(7) Set ignition timing to specifications (refer to
Specification Label on engine compartment hood).
(8) Perform a combustion analysis.
(9) Test fuel pump for pressure and vacuum (refer
to Group 14, Fuel System for the proper specifica­

tions).

(10) Inspect air filter element (refer to Group 0,
Lubrication and Maintenance for the proper proce­
dure).

(11) Inspect crankcase ventilation system (refer to
Group 0, Lubrication and Maintenance for the proper
procedure).
(12) For emission controls refer to Group 25, Emis­
sion Controls System for service procedures.
(13) Inspect and adjust accessory belt drives (refer
to Group 7, Cooling System for the proper adjust­
ments).

(14) Road test vehicle as a final test.

H0NIN6
CYLINDER
BORES
Before honing, stuff plenty of clean shop towels un­
der the bores and over the crankshaft to keep abra­ sive materials from entering the crankshaft area.
(1) Used carefully, the Cylinder Bore Sizing 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 scuffing, scoring or scratches. Usually a few strokes
will clean up a bore and maintain the required lim­
its.

CAUTION:
DO NOT use rigid type
hones
to remove

cylinder
wall
glaze.

(2) Deglazing of the cylinder walls may be done if
the cylinder bore is straight and round. Use a cylin­
der surfacing hone, Honing Tool C-3501, equipped
with 280 grit stones (C-3501-3810). 20-60 strokes, de­
pending on the bore condition, will be sufficient to
provide a satisfactory surface. Using honing oil C-3501-3880 or a light honing oil available from ma­
jor oil distributors.

CAUTION:
DO NOT use engine or
transmission
oil, mineral
spirits
or
kerosene.

9
- 4 ENGINES
•

RN861
Fig. 3 Clearance Measurement
CONNECTING ROD BEARING CLEARANCE Engine connecting rod bearing clearances can be
determined by use of Plastigage, or equivalent. The
following is the recommended procedures for the use of Plastigage:
(1) Remove oil film from surface to be checked.
Plastigage is soluble in oil.
(2) Place a piece of Plastigage across the entire
width of the bearing cap shell (Fig. 2). Position the
Plastigage approximately 6.35 mm (1/4 inch) off cen­
ter and away from the oil holes. In addition, suspect areas can be checked by placing the Plastigage in the
suspect area. (3) The crankshaft must be turned until the con­
necting rod to be checked starts moving toward the
top of the engine. Only then should the rod cap with
Plastigage in place be assembled. Tighten the rod
cap nut to 61 Nnn (45 ft. lbs.) torque. DO NOT ro­
tate the crankshaft or the Plastigage may be smeared, giving inaccurate results. (4) Remove the bearing cap and compare the width
of the flattened Plastigage with the scale provided on
the package (Fig. 3). Plastigage generally comes in 2 scales (one scale is in inches and the other is a met­
ric scale). Locate the band closest to the same width.
This band shows the amount of clearance. Differ­ ences in readings between the ends indicate the
amount of taper present. Record all readings taken (refer to Engine Specifications). (5) Plastigage is available in a variety of clearance
ranges. The 0.025-0.076 mm (0.001-0.003 inch) range
is usually the most appropriate for checking engine
bearing clearances.
REPAIR DAMAGED OR WORN THREADS Damaged or worn threads can be repaired. Essen­
tially, this repair consists of:
• Drilling out worn or damaged threads. • Tapping the hole with a special Heli-Coil Tap, or
equivalent.
• Installing an insert into the tapped hole.
This brings the hole back to its original thread

size.

CAUTION:
Be
sure
that
the tapped holes maintain
the original
center
line.

Heli-Coil tools and inserts are readily available
from automotive parts jobbers.

HYDROSTATIC
LOCK
When an engine is suspected of hydrostatic lock
(regardless of what caused the problem), follow the
steps below. (1) Perform the Fuel Pressure Release Procedure
(refer to Group 14, Fuel System). (2) Disconnect the negative cable from the battery.
(3) Inspect air cleaner, induction system and in­
take manifold to ensure system is dry and clear of
foreign material. (4) Place a shop towel around the spark plugs to
catch any fluid that may possibly be under pressure
in the cylinder head. Remove the plugs from the en­

gine.

CAUTION:
DO NOT use the starter motor to
rotate

the
crankshaft.
Severe
damage
could
occur.

(5) With all spark plugs removed, rotate the crank­
shaft using a breaker bar and socket.
(6) Identify the fluid in the cylinders (i.e. coolant,
fuel, oil, etc.).
(7) Make sure all fluid has been removed from the
cylinders. (8) Repair engine or components as necessary to
prevent this problem from occurring again.
(9) Squirt engine oil into the cylinders to lubricate
the walls. This will prevent damage on restart.
(10) Install new spark plugs. Tighten the spark
plugs to 41 N#m (30 ft. lbs.) torque. (11) Drain engine oil. Remove and discard the oil
filter.
(12) Install the drain plug. Tighten the plug to 34
N-m (25 ft. lbs.) torque.
(13) Install a new oil filter.
(14) Fill engine crankcase with the specified
amount and grade of oil (refer to Group 0, Lubrica­
tion and Maintenance). (15) Connect the negative cable to the battery.
(16) Start the engine and check for any leaks.

•

ENGINES
9 - S
ENGINE
DIAGNOSIS
Engine diagnosis is helpful in determining the
causes of malfunctions not detected and remedied by
routine tune-ups. These malfunctions may be classified as either per­
formance (e.g., engine idles rough and stalls) or me­ chanical (e.g., a strange noise). Refer to the Service Diagnosis—Performance chart
and the Service Diagnosis—Mechanical chart for pos­
sible causes and corrections of malfunctions. Refer to
Group 14, Fuel System for the fuel system diagnosis.

SERWIGE DIAGNOSIS (GASOLINE ENGINES)
-
PERFORMANCE
CONDITION

POSSIBLE
CAUSES
CORRECTION

ENGINE
WILL
NOT
START
1.
Weak
battery.

2.
Corroded
or
loose
battery
connections.

3.
Faulty
starter.

4.
Moisture
on
ignition wires and distributor
cap.

5.
Faulty
ignition
cables.

6.
Faulty
coil
or
control
unit.

7.
Incorrect
spark
plug
gap.
8.
Incorrect
ignition timing.
9.
Dirt
or
water
in
fuel
system.

10.
Faulty
fuel
pump.
1.
Test
battery
specific
gravity.
Charge
or
replace
as
necessary.

2. Clean
and
tighten
battery
connections.
Apply
a
coat
of light
mineral
grease
to
the terminals.
3. Refer to
Group
8A, Battery/Starter/Charging
System
Diagnostics.

4. Wipe
wires
and
cap
clean
and
dry.
5.
Replace
any
cracked
or
shorted
cables.

6.
Test
and
replace,
if
necessary
(refer
to
Group
8D,
Ignition
System).

7.
Set
gap
(refer
to
Group
8D, Ignition
System).

8. Refer to
Group
8D, Ignition
System.

9. Clean
system
and
replace
fuel
filter.

10. Install new
fuel
pump
(refer
to
Group
14,
Fuel
System).

ENGINE
STALLS
OR

ROUGH
IDLE
1.
Idle
speed
set
too
low.
2.
Idle
mixture
too
lean
or
too
rich.
3. Leak in
intake
manifold.
4. Worn or burned distributor
rotor.

5.
Incorrect
ignition wiring.
6.
Faulty
coil.

7.
EGR
valve leaking.
1.
Refer to
Group
14,
Fuel
System.

2. Refer to
Group
14,
Fuel
System.

3.
Inspect
intake
manifold
gasket
and
vacuum
hoses.
Replace,
if
necessary
(refer
to
Group
11,
Exhaust
System
&
Intake

Manifold).

4.
Install new distributor
rotor.

5. Install
correct
wiring.
6.
Test
and
replace,
if
necessary
(refer
to
Group
8D,
Ignition
System).

7.
Test
and
replace,
if
necessary
(refer
to
Group
25,
Emissions
Control
System).

J9309-105

9
- 6
ENGINES
•

SERVICE DIAGNOSIS (GASOLINE ENGINES)
•
PERFORMANCE (CONT.)

1
CONDITION

POSSIBLE
CAUSES
^
CORRECTION

1
ENGINE
LOSS
OF
POWER
1.
Incorrect ignition timing.
2. Worn or burned distributor
rotor.
3. Worn distributor shaft.

4.
Dirty
or
incorrectly
gapped
spark
plugs.

5.
Dirt
or
water
in
fuel
system.

6.
Faulty
fuel
pump.

7.
Incorrect valve timing.
8.
Blown
cylinder head
gasket.

9.
Low
compression.

10.
Burned,
warped or
pitted
valves.

11.
Plugged
or
restricted
exhaust
system.

12. Faulty ignition
cables.

13. Faulty coil.
1.
Refer
to
Group
8D, Ignition
System.

2. install new distributor
rotor.

3.
Remove
and
repair
distributor
(refer
to
Group
8D, Ignition
System).

4.
Clean
plugs
and
set gap
(refer
to
Group
8D, Ignition
System).

5. Clean
system
and replace
fuel
filter.

6. Install new
fuel
pump.

7.
Correct
valve
timing.
8. Install new cylinder head
gasket.

9.
Test
compression
of
each
cylinder.

10.
Install new
valves.
11.
Install new
parts,
as
necessary.

12.
Replace
any cracked or
shorted
cables.

13.
Test
and
replace,
as
necessary
(refer
to
Group
8D, Ignition
System).

ENGINE
MISSES
ON

ACCELERATION
1.
Dirty
or
gap set
too
wide
in spark
plug.
2. Incorrect ignition timing.
3.
Dirt
in
fuel
system.

4.
Burned,
warped or
pitted
valves.
5. Faulty coil.
1.
Clean spark
plugs
and set gap
(refer
to
Group
8D, Ignition

System).

2. Refer to
Group
8D, Ignition
System.

3. Clean
fuel
system.

4.
Install new
valves.

5.
Test
and
replace,
if
necessary,
(refer
to
Group
8D, Ignition
System).

ENGINE
MISSES
AT HIGH

SPEED
1.
Dirty
or
gap set too
wide
in spark
plug.
2. Worn distributor shaft.
3. Worn or burned distributor
rotor.

4. Faulty
coil.

5. Incorrect ignition timing.
6.
Dirty
injector
in
throttle
body.
7.
Dirt
or
water
in
fuel
system.
1.
Clean
spark
plugs
and
set gap
(refer
to
Group
8D, Ignition

System).

2.
Remove
and
repair
distributor
(refer
to
Group
8D,
Ignition
System).

3. Install new distributor
rotor.

4.
Test
and replace,
as
necessary
(refer
to
Group
8D, Ignition
System).

5.
Refer
to
Group
8D, Ignition
System.

6.
Clean
injector.

7.
Clean
system
and replace
fuel
filter.

J9309-106

•

ENGINES
9 - 7 SERVICE DIAGNOSIS (GASOLINE ENGINES) - MECHANICAL

CONDITION
PSSSI1LI
CAUSIS
CORRECTION

NOISY
VALVES
1. High
or
low oil
level
in

crankcase.

2. Thin or
diluted
oil.

3.
Low
oil
pressure.
4.
Dirt
in
tappets/lash
adjusters.

5. Bent
push
rods.
6. Worn rocker arms.
7.
Worn
tappets/lash
adjusters.

8.
Worn
valve
guides.

9.
Excessive
runout
of
valve
seats
on
valve
faces.
1.
Check
for
correct oil
level
(refer
to
Group
0,
Lubrication and
Maintenance).
2. Change oil
(refer
to Group
0,
Lubrication and Maintenance).
3. Check engine oil level.
4. Clean hydraulic tappets/hydraulic lash adjusters.
5. Install new
push
rods.
6. Inspect oil supply to rocker arms.
7. Install new hydraulic tappets/hydraulic lash adjusters. 8. Ream and install new valves
with
oversize stems.
9. Grind valve seats and valves.

CONNECTING
ROD
NOISE
1.
Insufficient oil supply.

2.
Low oil
pressure.

3.
Thin
or
diluted
oil.
4.
Excessive
bearing
clearance.
5. Connecting rod
journal
out-of- round.
6. Misaligned connecting rods.
1.
Check engine oil
level
(refer
to Group
0,
Lubrication and
Maintenance).
2. Check engine oil level. Inspect oil pump
relief
valve and spring.
3. Change oil to correct
viscosity.

4. Measure bearings for correct clearance. Repair as necessary, 5. Replace crankshaft or grind journals.

6.
Replace
bent
connecting rods.

MAIN
BEARING
NOISE
1.
Insufficient oil supply.
2 Low
oil
pressure.
3. Thin or
diluted
oil.
4.
Excessive
bearing clearance. 5.
Excessive
end play.
6. Crankshaft
journal
out-of-round, worn,
7.
Loose
flywheel
or
torque

converter.
1.
Check engine oil
level
(refer
to Group
0,
Lubrication and
Maintenance).
2. Check engine oil level. Inspect oil pump
relief
valve and spring.
3. Change oil to correct
viscosity.

4. Measure bearings for correct clearance. Repair as necessary. 5. Check No.
3
main bearing for
wear
on flanges.
6. Grind journals
or
replace crankshaft.
7. Tighten to correct torque.

OIL
PRESSURE
DROP
1.
Low oil level.
2. Faulty oil pressure sending
unit.

3. Low
oil
pressure.
4.
Clogged
oil
filter.

5 Worn parts in
oil
pump.
6. Thin or
diluted
oil.
7.
Excessive
bearing clearance. 8.
Oil
pump
relief
valve stuck.
9. Oil pump suction
tube
loose,
bent
or cracked.

10.
Oil pump cover warped
or
cracked.
1.
Check engine oil level.
2. Install new sending
unit.

3. Check sending
unit
and check main bearing oil clearance.
4. Install new oil
filter.

5. Replace worn parts or pump. 6. Change oil to correct
viscosity.

7. Measure bearings for correct clearance.
8. Remove valve and inspect, clean and install. 9. Remove oil pan and install new tube,
if
necessary.
10. Install new oil pump.

OIL
LEAKS
1.
Misaligned or
deteriorated

gaskets.
2.
Loose
fastener, broken
or
porous
metal
part.
1. Replace the gasket.
2. Tighten,
repair
or replace the
part.

OIL
PUMPING
AT
RINGS;
SPARK
PLUGS
FOULING
1.
Worn, scuffed
or broken
rings.
2. Carbon in oil ring
slot.

3.
Rings
fitted
too
tightly
in grooves.
4. Worn valve guides.
5. Leaking
intake
gasket.
6. Leaking valve guide
seals.

7. Dislodged valve guide
seals.
1.
Hone cylinder bores and install new rings.
2. Install new rings.
3. Remove the rings. Check
grooves.
If
grooves
are not proper width, replace piston.
4. Ream guides and replace valves
with
oversize valves and
seals.

5. Replace gasket and tighten
intake
manifold
to
proper torque.
6. Replace
seals.

7. Seat
valve guide
seals
or
replace, as needed.
J9209-58

9
- 10
ENGINES
— _
•
CONDITION

possmu
CLOSES
CORRECTION

ROUGH
IDLE

(IRREGULARLY
FIRING

OR
ENGINE
SHAKING)
(Cont'd)
High
pressure
fuel
leaks.

Air In the
fuel
system.
Correct leaks in the high pressure lines, fittings or
delivery

valves.

Bleed the
fuel
system and
eliminate
the source of the air.

Sticking
needle
valve
in an
injector.
Check and replace the
injector
with
the sticking
needle
valve.

ENGINE
RUNS
ROUGH

OR
MISFIRING
Fuel
injection
lines
leaking.

Correct leaks in the high pressure lines, fittings,
injector
sealing

washers
or
delivery
valves.
Air in the
fuel
or the
fuel
supply
is
inadequate.
Check the flow through the
filter
and bleed the system. Locate
and
eliminate
the air source.

Contaminated
fuel.
Verify
by operating the engine
with
clean
fuel
from a temporary

supply
tank. Check for presence of gasoline. Replace
fuel/water

separator
filter.

Incorrect
valve
adjustment.
Check for a
bent
push rod and adjust valves. Replace push rod,
if necessary.

Injection
pump
timing
incorrect.
Check/time pump
(refer
to Group 14,
Fuel
System).

Improperly
operating
injectors.
Replace inoperative injectors.
Defective
injection
pump

(delivery
valves).
Replace
injection
pump.

Camshaft
out of
time.
Check/correct gear
train
timing alignment.

Damaged
camshaft or
tappets.
Inspect camshaft valve
lift.
Replace camshaft and tappets.

ENGINE
RPM WILL NOT

REACH
RATED
SPEED
Engine
overloaded.

Verify
high
idle
speed
without
load. Investigate operation to be
sure correct gear is being used.

Improperly
operating
tachometer.
Verify
engine speed
with
hand tachometer—correct as required.

Throttle
linkage
worn
or
incorrectly
adjusted.
Adjust linkage for stop-to-stop
fuel
control
lever
travel.
Replace
linkage if necessary.
Partially
engaged
mechanical

shutdown
lever.
Adjust and place shutdown
lever
in the run position.

Inadequate
fuel
supply. Check the
fuel
flow through the system to locate the reason for
inadequate
fuel
supply—correct as required.

Improperly
operating
injection

pump.
Replace
injection
pump.

LOW
POWER
Fuel
control
lever
not
moving
to

full
throttle.
Check/correct for stop-to-stop
travel.

Mechanical/shutdown
lever
partially
engaged.
Check to see if the shutdown
lever
is in run position.

High
oil
level.
Check/correct oil level.

Engine
overloaded.
Check for added loading from accessories or driven units, brakes

dragging
and
other
changes in vehicle loading. Repair/replace as
needed.
J9109-264
SERVICE
DIAGNOSIS (DIESEL ENGINE)
•
PERFORMANCE (CONT.)

9
- 14
ENGINES
— — — •

SERVICE
DIAGNOSIS (DIESEL ENGINE)
•
MECHANICAL

CONDITION

r— ———
POSSIBLE
CAUSES
CORRECTION

LUBRICATING
OIL

PRESSURE
LOW Low oil
level.

(a)
Check
and
fill
with
clean engine oil.
(b) Check for a severe
external
oil leak
that
could reduce the pressure.
Oil viscosity thin,
diluted
or wrong specification.
Verify
the correct oil is being
used.
Check for oil dilution. Refer
to Contaminated Lube Oil (Engine Diagnosis—Mechanical).
Improperly operating pressure

switch/gauge.
Verify
the pressure switch is functioning correctly. If not,
replace switch/gauge.
Relief valve stuck open. Check/replace valve.

Plugged
oil
filter.
Change
oil
filter.
Oil
filter
change
interval
may need to be
revised.
If cooler was replaced, shipping

plugs
left
in cooler. Check/remove shipping
plugs.

If pump replaced, four cylinder
oil pump installed in a six
cylinder engine.
Verify
that
the correct pump is installed. If not, install an oil
pump for a six cylinder engine.

Loose
or
missing
cup
plugs.
Check and replace cup
plugs.

Worn oil pump. Check and replace oil pump.

Suction
tube
loose or seal leaking. Check and replace seal.

Loose
main bearing cap. Check and
install
new bearings and tighten cap to proper torque.
Worn bearings or wrong bearings installed. inspect and replace connecting rod or main bearings. Check and
replace piston cooling nozzles.

J9109-237