Engine distributors WSG-1068 User manual

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 WSG‐1068 
6.8LITER
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INDUSTRIALENGINESERVICEMANUAL
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EDI#1050180
March,2009
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Section
Index
Reproduction in any manner, in whole or in
part, is prohibited without the express
permission in writing from:
Engine Distributors Inc.
Engine Distributors Inc policy is one of
continuous improvement and while every effort
is made to ensure that this publication is up to
date and correct in all respects, the right to
change prices, specifications and equipment at
any time without notice is reserved. Accordingly
this publication is not to be regarded as a
final description of any individual engine.
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HEALTH & SAFETY
WARNING: THE FOLLOWING HEALTH AND SAFETY RECOMMENDATIONS SHOULD BE
CAREFULLY OBSERVED
WARNING: CARRYING OUT CERTAIN OPERATIONS AND HANDLING SOME
SUBSTANCES CAN BE DANGEROUS OR HARMFUL TO THE OPERATOR IF THE
CORRECT SAFETY PRECAUTIONS ARE NOT OBSERVED. SOME SUCH PRECAUTIONS
ARE RECOMMENDED AT THE APPROPRIATE POINTS IN THIS BOOK.
WARNING: WHILE IT IS IMPORTANT THAT THESE RECOMMENDED SAFETY
PRECAUTIONS ARE OBSERVED, CARE NEAR MACHINERY IS ALWAYS NECESSARY,
AND NO LIST CAN BE EXHAUSTIVE. ALWAYS BE CAUTIOUS TO AVIOD POTENTIAL
SAFETY RISKS.
The following recommendations are for general guidance:
1. Always wear correctly fitting protective clothing which should be laundered regularly. Loose or baggy clothing
can be extremely dangerous when working on running engines or machinery. Clothing which becomes
impregnated with oil or other substances can constitute a health hazard due to prolonged contact with the skin
even through underclothing.
2. So far as practicable, work on or close to engines or machinery only when they are stopped. If this is not
practicable, remember to keep tools, test equipment and all parts of the body well away from the moving parts
of the engine or equipment—fans, drive belts and pulleys are particularly dangerous. The electric cooling fan
used on some installations is actuated automatically when the coolant reaches a specified temperature. For this
reason, care should be taken to ensure that the ignition/isolating switch is OFF when working in the vicinity of
the fan as an increase in coolant temperature may cause the fan suddenly to operate.
3. Avoid contact with exhaust pipes, exhaust manifolds and silencers when an engine is, or has recently been
running; these can be very hot and can cause severe burns.
4. Many liquids used in engines or vehicles are harmful if taken internally or splashed into the eyes. In the event of
accidentally swallowing gasoline (petrol), oil, diesel fuel, antifreeze, battery acid etc, do NOT encourage vomiting
and OBTAIN QUALIFIED MEDICAL ASSISTANCE IMMEDIATELY.
Wear protective goggles when handling liquids which are harmful to the eyes; these include ammonia and battery
acid. If any of these substances are splashed in the eyes, wash out thoroughly with clean water and OBTAIN
QUALIFIED MEDICAL ASSISTANCE IMMEDIATELY.
IMPORTANT SAFETY NOTICE
Appropriate service methods and proper repair procedures are essential for the safe, reliable operation of all
industrial engines as well as the personal safety of the individual doing the work. This Service Manual provides
general directions for accomplishing service and repair work with tested, effective techniques. Following them will
help assure reliability.

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WSG-1068 GENERAL INFORMATION
INDEX
Subject Page
General Information
Introduction ............................................................................................................................................
Safety Notice..........................................................................................................................................
Notes, Cautions, and Warnings.............................................................................................................
Battery Handling and Charging .............................................................................................................
Forward .................................................................................................................................................
Engine Identification...............................................................................................................................
Parts and Service ..................................................................................................................................
Diagnosis and Testing
Special Tools.........................................................................................................................................
Inspection and Verification ....................................................................................................................
Symptom Chart ......................................................................................................................................
Engine Oil Leaks ...................................................................................................................................
Compression Tests ................................................................................................................................
Cylinder Leakage Detection ..................................................................................................................
Intake Manifold Vacuum Test.................................................................................................................
Excessive Engine Oil Consumption .......................................................................................................
Oil Pressure Test....................................................................................................................................
Valve Train Analysis – Static..................................................................................................................
Valve Train Analysis – Dynamic.............................................................................................................
Camshaft Lobe Lift ................................................................................................................................
Hydraulic Lash Adjuster .........................................................................................................................
General Service Procedures
Camshaft Journal Diameter....................................................................................................................
Camshaft Journal Clearance..................................................................................................................
Camshaft Lobe Surface..........................................................................................................................
Camshaft Lobe Lift ................................................................................................................................
Camshaft Runout ...................................................................................................................................
Crankshaft Main Bearing Journal Diameter ...........................................................................................
Crankshaft Main Bearing Journal Taper.................................................................................................
Crankshaft Main Bearing Journal Clearance..........................................................................................
Bearing Inspection .................................................................................................................................
Crankshaft End Play...............................................................................................................................
Crankshaft Runout .................................................................................................................................
Cylinder Bore Taper ..............................................................................................................................
Cylinder Bore Out-of-Round...................................................................................................................
Piston Inspection ...................................................................................................................................
Piston Diameter.....................................................................................................................................
Piston to Cylinder Bore Clearance ........................................................................................................
Piston Selection .....................................................................................................................................
Piston Ring End Gap..............................................................................................................................
Piston Ring-to-Groove Clearance ..........................................................................................................
Crankshaft Connecting Rod Journal Diameter.......................................................................................
Crankshaft Connecting Rod Journal Taper............................................................................................
Connecting Rod Cleaning ......................................................................................................................
Connecting Rod Larger End Bore .........................................................................................................
Piston Pin Diameter................................................................................................................................
Connecting Rod Bushing Diameter .......................................................................................................
Connecting Rod Bend ...........................................................................................................................
Connecting Rod Twist ...........................................................................................................................
Connecting Rod Piston Pin Side Clearance...........................................................................................
Connecting Rod Journal Clearance .......................................................................................................
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WSG-1068 GENERAL INFORMATION
INDEX (CONT.)
Subject Page
General Service Procedures
Bearing Inspection ......................................................................................................................................
Roller Follower Inspection...........................................................................................................................
Hydraulic Lash Adjuster Inspection ............................................................................................................
Valve Stem Diameter ..................................................................................................................................
Valve Stem-to-Valve Guide Clearance........................................................................................................
Valve Inspection..........................................................................................................................................
Valve Guide Inner Diameter........................................................................................................................
Valve Guide Reaming .................................................................................................................................
Valve Spring Installed Length......................................................................................................................
Valve Spring Free Length............................................................................................................................
Valve Spring Out-of-Square ........................................................................................................................
Valve Spring Compression Pressure ..........................................................................................................
Valve and Seat Refacing Measurements....................................................................................................
Valve Seat Width.........................................................................................................................................
Valve Seat Runout ......................................................................................................................................
Flywheel Inspection.....................................................................................................................................
Oil Pump Gear Radial Clearance................................................................................................................
Oil Pump Rotor Inspection ..........................................................................................................................
Oil Pump Side Clearance............................................................................................................................
Cylinder Bore Honing ..................................................................................................................................
Cylinder Bore Cleaning ...............................................................................................................................
Cylinder Block Repair - Cast Iron Porosity Defects.....................................................................................
Cylinder Block Core Plug Replacement ......................................................................................................
Cylinder Head - Distortion ...........................................................................................................................
Spark Plug Thread Repair...........................................................................................................................
Exhaust Manifold Straightness....................................................................................................................
SPECIFICATIONS....................................................................................................................................................
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WSG-1068 GENERAL INFORMATION
GENERAL INFORMATION
Introduction
This section covers various engine tests, adjustments, service procedures and cleaning/inspection procedures. Engine
assembly and service specifications appear at the end of the Section 02.
For engine disassembly, assembly, installation, adjustment procedures and specifications, refer to Section 02.
This WSG-1068 engine incorporates a closed-type crankcase ventilation system.
To maintain the required performance level, the fuel system, ignition system and engine must be kept in good operating
condition and meet recommended adjustment specifications.
Before replacing damaged or worn engine components such as the crankshaft, cylinder head, valve guide, valves,
camshaft or cylinder block, make sure part(s) is not serviceable.
WARNING: TO AVOID THE POSSIBILITY OF PERSONAL INJURY OR DAMAGE, DO NOT OPERATE THE
ENGINE UNTIL THE FAN BLADE HAS FIRST BEEN EXAMINED FOR POSSIBLE CRACKS OR SEPARATION.
CAUTION: Use of abrasive grinding discs to remove gasket material from the engine sealing surfaces during
repair procedures can contribute to engine damage and wear. Airborne debris and abrasive grit from
the grinding disc may enter the engine through exposed cavities causing premature wear and eventual engine
damage.
Engine Distributors Inc does not recommend using abrasive grinding discs to remove engine gasket material. Use manual
gasket scrapers for removing gasket material from the engine sealing surfaces.
Take added care to prevent scratching or gouging aluminum sealing surfaces.

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WSG-1068 GENERAL INFORMATION
Safety Notice
There are numerous variations in procedures, techniques, tools and parts for servicing equipment, as well as in the skill of
the individual doing the work. This manual cannot possibly anticipate all such variations and provide advice or cautions as
to each. Accordingly, anyone who departs from the instructions provided in this Manual must first establish that neither
personal safety nor equipment integrity are compromised by the choice of methods, tools or parts.
Notes, Cautions, and Warnings
As you read through the procedures, you will come across NOTES, CAUTIONS, and WARNINGS. Each one is there for a
specific purpose. NOTES gives you added information that will help you to complete a particular procedure. CAUTIONS
are given to prevent you from making an error that could damage the equipment. WARNINGS remind you to be especially
careful in those areas where carelessness can cause personal injury. The following list contains some general
WARNINGS that you should follow when you work on the equipment.
GENERAL WARNINGS:
TO HELP AVOID INJURY:
ALWAYS WEAR SAFETY GLASSES FOR EYE PROTECTION.
USE SAFETY STANDS WHENEVER A PROCEDURE REQUIRES YOU TO BE UNDER THE EQUIPMENT.
BE SURE THAT THE IGNITION SWITCH IS ALWAYS IN THE OFF POSITION, UNLESS OTHERWISE
REQUIRED BY THE PROCEDURE.
SET THE PARKING BRAKE (IF EQUIPPED) WHEN WORKING ON THE EQUIPMENT. IF YOU HAVE AN
AUTOMATIC TRANSMISSION, SET IT IN PARK (ENGINE OFF) OR NEUTRAL (ENGINE ON) UNLESS
INSTRUCTED OTHERWISE FOR A SPECIFIC OPERATION. PLACE WOOD BLOCKS (4”X 4” OR LARGER)
TO THE FRONT AND REAR SURFACES OF THE TIRES TO PROVIDE FURTHER RESTRAINT FROM
INADVERTENT EQUIPMENT MOVEMENT.
OPERATE THE ENGINE ONLY IN A WELL VENTILATED AREA TO AVOID THE DANGER OF CARBON
MONOXIDE.
KEEP YOURSELF AND YOUR CLOTHING AWAY FROM MOVING PARTS WHEN THE ENGINE IS
RUNNING, ESPECIALLY THE FAN BELTS.
TO PREVENT SERIOUS BURNS, AVOID CONTACT WITH HOT METAL PARTS SUCH AS THE RADIATOR,
EXHAUST MANIFOLD, TAIL PIPE, CATALYTIC CONVERTER AND MUFFLER.
DO NOT SMOKE WHILE WORKING ON THE EQUIPMENT.
ALWAYS REMOVE RINGS, WATCHES, LOOSE HANGING JEWELRY, AND LOOSE CLOTHING BEFORE
BEGINNING TO WORK ON THE EQUIPMENT. TIE LONG HAIR SECURELY BEHIND THE HEAD.
KEEP HANDS AND OTHER OBJECTS CLEAR OF THE RADIATOR FAN BLADES. ELECTRIC COOLING
FANS CAN START TO OPERATE AT ANY TIME BY AN INCREASE IN UNDERHOOD TEMPERATURES,
EVEN THOUGH THE IGNITION IS IN THE OFF POSITION. THEREFORE, CARE SHOULD BE TAKEN TO
ENSURE THAT THE ELECTRIC COOLING FAN IS COMPLETELY DISCONNECTED WHEN WORKING
UNDER THE HOOD.

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WSG-1068 GENERAL INFORMATION
Battery Handling and Charging
The handling and correct use of lead acid batteries is not as hazardous provided that sensible precautions are observed
and that operatives have been trained in their use and are adequately supervised.
It is important that all labelling on the battery is carefully read, understood and complied with. The format of the following
symbols and labels is common to most brands of lead acid battery.
NOTE: Observe all manufacturers’ instructions when using charging equipment.
CAUTION: Batteries should not be charged in the vehicle or equipment. May damage electrical components.

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WSG-1068 GENERAL INFORMATION
Forward
This book contains operating and maintenance instructions for the engine(s) listed on the title page.
The life of your engine unit and the delivery of the high performance built into it will depend on the care it receives
throughout its life. It is the operator’s responsibility to ensure that the engine is correctly operated and that the
maintenance operations outlined in this book are carried out regularly after the specified hours of operation have been
reached. We consider it to be in your interests to enlist the aid of an authorized EDI Distributor not only when repairs are
required but also for regular maintenance. Distributors are listed at the back of this manual.
Regular maintenance will result in minimal operating costs.
Engines manufactured by Ford Motor Company are available through Engine Distributors Incorporated. When in need of
parts or service, contact your local Authorized Distributor. In overseas territories, in the event of difficulties, communicate
directly with the supervising Ford affiliated Company in your area whose address appears at the end of this book.
Where the terms “Right” or “Left” occur in this publication, they refer to the respective sides of the engine when viewed
from the rear or flywheel end.
Pistons and valves are numbered from the front or timing cover end of the engine commencing at No. 1.
You may find that your engine assembly includes optional equipment not specifically covered in the following text.
Nevertheless, the maintenance procedures outlined in this book still apply to your engine.

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WSG-1068 GENERAL INFORMATION
Engine Identification
Because of such a wide range of industrial engines – manufactured both in the U.S. and overseas – it is important that
you have as complete identification of the engine as possible in order to provide the correct replacement parts. New
engines being shipped include a standard parts listing describing the parts which does not tell the owner the part number.
It remains a distributor function to identify the part number. The key to identifying the engine is the identification decal
mounted on the engine rocker cover. That decal provides not only the engine serial number, but also the exact model or
type, options and S.O. (Special Order). The combination of that data permits you to isolate the precise engine, build level
and customer so you can determine the correct replacement parts.
Engine Identification Decal
An identification Decal is affixed to the valve cover of the engine. The decal contains the engine serial number which
identifies this unit from all others. Use all numbers when seeking information or ordering replacement parts for this engine.
For a handy reference, keep this information recorded in a separate location.

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WSG-1068 GENERAL INFORMATION
Parts and Service
Replacement parts can be obtained through your local EDI Distributors listed in the back portion of this manual. They also
may be found in the yellow pages under “Engines” or contact Engine Distributors.
Engine Distributors Inc are equipped to perform major and minor repairs. They are anxious to see that all of your
maintenance and service needs are quickly and courteously completed.

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WSG-1068 GENERAL INFORMATION
DIAGNOSIS AND TESTING
Special Tools

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WSG-1068 GENERAL INFORMATION
Inspection and Verification
1. Verify the customer concern by operating the engine to duplicate the condition.
2. Visually inspect for obvious signs of mechanical and electrical damage:
Engine coolant leaks.
Engine oil leaks.
Fuel leaks.
Damaged or severely worn pads.
Loose mounting bolts, studs, and nuts.
3. If the inspection reveals obvious concerns that can be readily identified, repair as required.
4. If the concerns remain after the inspection, determine the symptoms and go to the symptom
chart.

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WSG-1068 GENERAL INFORMATION
Symptom Chart
Condition Possible Source Action

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WSG-1068 GENERAL INFORMATION

WSG-1068 GENERAL INFORMATION
Engine Oil Leaks
NOTE: When diagnosing engine oil leaks, the source
and location of the leak must be positively identified
prior to service.
Prior to performing this procedure, clean the cylinder
block, cylinder heads, valve covers, oil pan and flywheel
with a suitable solvent to remove all traces of oil.
Fluorescent Oil Additive Method
Use the 12 Volt Master UV Diagnostic Inspection Kit to
perform the following procedure for oil leak diagnosis.
1. Clean the engine with a suitable solvent to
remove all traces of oil.
2. Drain engine oil crankcase and refill with
recommended oil, premixed with Diesel Engine
Oil Dye 164-R3705 meeting Ford specification
ESEM9C103- B1 or equivalent. Use a minimum
14.8 ml (0.5 ounce) to a maximum 29.6 ml (1
ounce) of fluorescent additive to all engines. If
the oil is not premixed, fluorescent additive must
first be added to crankcase.
3. Run the engine for 15 minutes. Stop the engine
and inspect all seal and gasket areas for leaks
using the 12 Volt Master UV diagnostic
Inspection Kit. A clear bright yellow or orange
area will identify the leak. For extremely small
leaks, several hours may be required for the
leak to appear.
4. If necessary, pressurize the main oil gallery
system to locate leaks due to improperly sealed,
loose or cocked plugs.
5. Repair all leaks as required.
Pressure Method
The crankcase can be pressurized to locate oil leaks.
The following materials are required to fabricate the tool
to be used:
air supply and air hose
air pressure gauge that registers pressure in 4 kPa
(1 psi) increments
air line shutoff valve
appropriate fittings to attach the above parts to oil
fill, PCV grommet hole and crankcase ventilation
tube
appropriate plugs to seal any openings leading to
the crankcase
a solution of liquid detergent and water to be applied
with a suitable applicator such as a squirt bottle or
brush
Fabricate the air supply hose to include the air line
shutoff valve and the appropriate adapter to permit the
air to enter the engine through the crankcase ventilation
tube. Fabricate the air pressure gauge to a suitable
adapter for installation on the engine at the oil filler
opening.
Testing Procedure
Open the air supply valve until the pressure gauge
maintains 34 kPa (5 psi).
Inspect sealed or gasketed areas for leaks by
applying a solution of liquid detergent and water
over areas for formation of bubbles which
indicates leakage.
Leakage Points - Above Engine
Examine the following areas for oil leakage.
valve cover gaskets
intake manifold gaskets
cylinder head gaskets
oil bypass filter
oil level indicator tube connection
oil pressure sensor
Leakage Points - Under Engine
oil pan gaskets
oil pan sealer
oil pan rear seal
engine front cover gasket
crankshaft front seal
crankshaft rear oil seal
crankshaft main bearing cap side bolts
Leakage Points - with Flywheel Removed
NOTE: Air leakage in the area around a crankshaft rear
oil seal does not necessarily indicate a crankshaft rear
oil seal leak. However, if no other cause can be found
for oil leakage, assume that the crankshaft rear oil seal
is the cause of the oil leak.
NOTE: Light foaming equally around valve cover bolts
and crankshaft seals is not detrimental; no repairs are
required.
crankshaft rear oil seal
rear main bearing cap parting line
rear main bearing cap and seals
flywheel mounting bolt holes (with flywheel installed)
camshaft rear bearing covers or pipe plugs at the
end of oil passages
Oil leaks at crimped seams in sheet metal parts and
cracks in cast or stamped parts can be detected when
pressurizing the crankcase.

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WSG-1068 GENERAL INFORMATION
Compression Tests
Compression Gauge Check
1. Make sure the oil in the crankcase is of the
correct viscosity and at the proper level and that
the battery is properly charged. Operate until
the engine is at normal operating temperature.
Turn the ignition switch to the OFF position,
then remove all the spark plugs.
2. Set the throttle plates in the wide-open position.
3. Install a Compression Tester in the No. 1
cylinder.
4. Install an auxiliary starter switch in the starting
circuit. With the ignition switch in the OFF
position, and using the auxiliary starter switch,
crank the engine a minimum of five compression
strokes and record the highest reading. Note the
approximate number of compression strokes
required to obtain the highest reading.
5. Repeat the test on each cylinder, cranking the
engine approximately the same number of
compression strokes.
Test Results
The indicated compression pressures are considered
within specification if the lowest reading cylinder is
within 75 percent of the highest reading. Refer to the
Compression Pressure Limit Chart.
If one or more cylinders reads low, squirt approximately
one tablespoon of clean engine oil meeting Ford
specification ESE-M2C153-E on top of the pistons in
the low-reading cylinders. Repeat the compression
pressure check on these cylinders.
Compression Pressure Limit Chart
Interpreting Compression Readings
1. If compression improves considerably, with the
addition of oil, piston rings are faulty.
2. If compression does not improve with oil, valves
are sticking or seating improperly.
3. If two adjacent cylinders indicate low
compression pressures and squirting oil on
each piston does not increase compression, the
head gasket may be leaking between cylinders.
Engine oil or coolant in cylinders could result
from this condition.
Use the Compression Pressure Limit Chart when
checking cylinder compression so that the lowest
reading is within 75 percent of the highest reading.

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WSG-1068 GENERAL INFORMATION
Cylinder Leakage Detection
When a cylinder produces a low reading, use of the
Engine Cylinder Leak Detection/Air Pressurization Kit
will be helpful in pinpointing the exact cause.
The leakage detector is inserted in the spark plug hole,
the piston is brought up to dead center on the
compression stroke, and compressed air is admitted.
Once the combustion chamber is pressurized, a special
gauge included in the kit will read the percentage of
leakage. Leakage exceeding 20 percent is excessive.
While the air pressure is retained in the cylinder, listen
for the hiss of escaping air. A leak at the intake valve will
be heard in the throttle body. A leak at the exhaust valve
can be heard at the tail pipe. Leakage past the piston
rings will be audible at the positive crankcase ventilation
(PCV) connection. If air is passing through a blown
head gasket to an adjacent cylinder, the noise will be
evident at the spark plug hole of the cylinder into which
the air is leaking. Cracks in the cylinder blocks or gasket
leakage into the cooling system may be detected by a
stream of bubbles in the radiator.
Oil Leak and Valve Stem Seal Test
The cylinder leakage detector tests for engine oil leaks
and checks the valve stem seals for leakage.
1. Plug all crankcase openings except the one
used for connecting the leakage detector.
2. Connect the Engine Cylinder Leak Detection/Air
Pressurization Kit to a crankcase opening (an oil
level indicator tube is convenient). Adjust the air
pressure to approximately 34 kPa (5 psi).
3. Using a solution of liquid soap and water, brush
the solution along the gasket sealing surfaces
and bearing seals. Look for bubbles or foam.
4. Remove the spark plugs and rotate the
crankshaft slowly with a wrench. Check for large
amounts of air escaping into the cylinders as
each intake valve and exhaust valve opens.
5. The spark plugs on the leaking cylinders will
probably show deposits of burned oil.
Intake Manifold Vacuum Test
Bring the engine to normal operating temperature.
Connect the Vacuum/Pressure Tester to the intake
manifold. Run the engine at the specified idle speed.
The vacuum gauge should read between 51-74 kPa
(15-22 in-Hg) depending upon the engine condition and
the altitude at which the test is performed. Subtract
4.0193 kPa (1 in-Hg) from the specified reading for
every 304.8 m (1,000 feet) of elevation above sea level.
The reading should be steady. If necessary, adjust the
gauge damper control (where used) if the needle is
fluttering rapidly. Adjust the damper until the needle
moves easily without excessive flutter.

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WSG-1068 GENERAL INFORMATION
Interpreting Vacuum Gauge Readings
A careful study of the vacuum gauge reading while the
engine is idling will help pinpoint trouble areas. Always
conduct other appropriate tests before arriving at a final
diagnostic decision. Vacuum gauge readings, although
helpful, must be interpreted carefully.
Most vacuum gauges have a normal band indicated on
the gauge face.
The following are potential gauge readings. Some are
normal; others should be investigated further.
1. NORMAL READING: Needle between 51-74
kPa (15-22 in-Hg) and holding steady.
2. NORMAL READING DURING RAPID
ACCELERATION AND DEACCELERATION:
When the engine is rapidly accelerated (dotted
needle), the needle will drop to a low reading
(not to zero). When the throttle is suddenly
released, the needle will snap back up to a
higher than normal figure.
3. NORMAL FOR HIGH-LIFT CAMSHAFT WITH
LARGE OVERLAP: The needle will register as
low as 51 kPa (15 in-Hg) but will be relatively
steady. Some oscillation is normal.
4. WORN RINGS OR DILUTED OIL: When the
engine is accelerated (dotted needle), the
needle drops to 0 kPa (0 in-Hg). Upon
deceleration, the needle runs slightly above 74
kPa (22 in-Hg).
5. STICKING VALVES: When the needle (dotted)
remains steady at a normal vacuum but
occasionally flicks (sharp, fast movement) down
and back about 13 kPa (4 in-Hg), one or more
valves may be sticking.
6. BURNED OR WARPED VALVES: A regular,
evenlyspaced, downscale flicking of the needle
indicates one or more burned or warped valves.
Insufficient hydraulic lash adjuster or hydraulic
lash adjuster (HLA) clearance will also cause this
reaction.
7. POOR VALVE SEATING: A small but regular
downscale flicking can mean one or more valves
are not seating.
8. WORN VALVE GUIDES: When the needle
oscillates over about a 13 kPa (4 in-Hg) range at
idle speed, the valve guides could be worn. As
engine speed increases, the needle will become
steady if guides are responsible.
9. WEAK VALVE SPRINGS: When the needle
oscillation becomes more violent as engine rpm
is increased, weak valve springs are indicated.
The reading at idle could be relatively steady.
10. LATE VALVE TIMING: A steady but low reading
could be caused by late valve timing.
11. IGNITION TIMING RETARDING: Retarded ignition
timing will produce a steady but somewhat low
reading.
12. INSUFFICIENT SPARK PLUG GAP: When spark
plugs are gapped too close, a regular, small
pulsation of the needle can occur.
13. INTAKE LEAK: A low, steady reading can be
caused by an intake manifold or throttle body
gasket leak.
14. BLOWN HEAD GASKET: A regular drop of fair
magnitude can be caused by a blown head
gasket or warped cylinder head-to-cylinder block
surface.
15. RESTRICTED EXHAUST SYSTEM: When the
engine is first started and is idled, the reading
may be normal, but as the engine rpm is
increased, the back pressure caused by a clogged
muffler, kinked tail pipe or other concerns will cause the
needle to slowly drop to 0 kPa (0 in-Hg). The needle then
may slowly rise. Excessive exhaust clogging will
cause the needle to drop to a low point even if the
engine is only idling.
When vacuum leaks are indicated, search out and
correct the cause. Excess air leaking into the system
will upset the fuel mixture and cause concerns such as
rough idle, missing on acceleration or burned valves. If
the leak exists in an accessory unit such as the power
brake booster, the unit will not function correctly. Always
fix vacuum leaks.

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WSG-1068 GENERAL INFORMATION
Excessive Engine Oil Consumption
The amount of oil an engine uses will vary with the way
the equipment is driven in addition to normal engine-to
engine variation. This is especially true during the first
340 hours or 16,100 km (10,000 miles) when a new
engine is being broken in or until certain internal engine
components become conditioned. Engines used in
heavy-duty operation may use more oil. The following
are examples of heavy-duty operation:
severe loading applications
sustained high speed operation
Engines need oil to lubricate the following internal
components:
cylinder block, cylinder walls
pistons, piston pins and rings
intake and exhaust valve stems
intake and exhaust valve guides
all internal engine components
When the pistons move downward, a thin film of oil is
left on the cylinder walls. As the engine is operated,
some oil is also drawn into the combustion chambers
past the intake and exhaust valve stem seals and
burned.
The following is a partial list of conditions that can affect
oil consumption rates:
engine size
operator driving habits
ambient temperature
quality and viscosity of the oil
Operating under varying conditions can frequently be
misleading. An engine that has been run for short hours
or in below-freezing ambient temperatures may have
consumed a “normal” amount of oil. However, when
checking engine oil level, it may measure up to the full
mark on the oil level dipstick due to dilution
(condensation and fuel) in the engine crankcase. The
engine might then be run at high speeds where the
condensation and fuel boil off. The next time the engine
oil is checked, it may appear that a liter (quart) of oil was
used in about 3 to 3-1/2 hours. This perceived 3 to 3-1/
2 hours per liter (quart) oil consumption rate causes
customer concern even though the actual overall oil
consumption rate is about 50 hours per liter (quart).
Make sure the selected engine oil meets Ford
specification WSS-M2C153-F and the recommended
API performance category “SJ” or higher and SAE
viscosity grade as shown in the equipment Owner’s or
Operators Engine handbook. It is also important that the
engine oil is changed at the intervals specified. Refer to
the Engine Operator’s handbook.
Oil Consumption Test
The following diagnostic procedure is used to determine
the source of excessive internal oil consumption.
NOTE: Oil use is normally greater during the first 300
hours of service. As hours increase, oil use generally
decreases. Engines in normal service should get at
least 31.7 hours per quart (900 miles per quart) after
300 hours of service. High speeds, heavy loads, high
ambient temperature and other factors may result in
greater oil use.
1. Determine customer’s engine load habits, such
as sustained high speed operation, extended
idle, heavy work loads and other considerations.
2. Verify that the engine has no external oil leak as
described under Engine Oil Leaks in the
Diagnosis and Testing portion of this section.
3. Verify that the engine has the correct oil level
dipstick.
4. Verify that the engine is not being run in an
overfilled condition. Check the oil level at least
five minutes after a hot shutdown with the
engine/vehicle parked on a level surface. In no
case should the level be above the top of the
cross-hatched area and the letter F in FULL. If
significantly overfilled, perform steps 5 through
9. If not proceed to step 10.
5. Drain the engine oil, remove and replace the oil
bypass filter and refill with one quart less than
the recommended amount.
6. Run the engine for three minutes (10 minutes if
cold), and allow the oil to drain back for at least
five minutes with the engine/vehicle on a level
surface.
7. Remove oil level dipstick and wipe clean.
CAUTION: Do not wipe with anything contaminated
with silicone compounds.
8. Reinstall the oil level dipstick, being sure to seat
it firmly in the oil level indicator tube. Remove
the oil level dipstick and draw a mark on the
back (unmarked) surface at the indicated oil
level. This level should be about the same as
the ADD mark on the face of the oil level
dipstick.
9. Add one quart of oil. Restart the engine and
allow to idle for at least two minutes. Shut off
the engine and allow the oil to drain back for at
least five minutes. Mark the oil level dipstick,
using the procedure above. This level may
range from slightly below the top of the cross-
hatched area to slightly below the letter F in
FULL.
10.Record the vehicle mileage or hours.