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KRYOTEC ENGINE
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OIL CONSUMPTION TEST AND DIAGNOSIS
The following diagnostic procedures are used to
determine the source of excessive internal oil
Consumption, these procedures and tests apply to
vehicles with 50,000 miles or less.
NOTE
Engine oil consumption may be greater than
normal during engine break-in. Repairs should be
delayed until vehicle has been driven at least
7,500 miles.
Severe service (high ambient temperature, short
trips, heavy loading, trailer towing, off-road, or law
enforcement use) may result in greater oil
consumption than normal.
Sustained high speed driving and high engine
RPM operation may result in increased oil
consumption.
Failure to comply with the recommended oil type
and viscosity rating, as outlined in the owner's
manual, may impact oil economy as well as fuel
economy.
Oil consumption may increase with vehicle age
and mileage due to normal engine wear.
NOTE
Because a few drops of external oil leakage per
mile can quickly account for the loss of one quart
of oil in a few hundred miles, ensure no external
engine oil leaks are present.
• Oil leakage is not the same as oil consumption
and all external leakage must be eliminated
before any action can be taken to verify and/or
correct oil consumption complaints.
• Verify that the engine has the correct oil level
dipstick and dipstick tube installed.
• Verify that the engine is not being run in an
overfilled condition. Check the oil level 15 minutes
after a hot shutdown with the vehicle parked on a
level surface. In no case should the level be
above MAX or the FULL mark on the dipstick.
OIL CONSUMPTION TEST
1. Check the oil level at least 15 minutes after a
hot shutdown.
2. If the oil level is low, top off with the proper
viscosity and API service level engine oil. Add one
bottle of MOPAR® 4-In-1 Leak Detection Dye into
the engine oil.
3. Tamper proof the oil pan drain plug, oil filter,
dipstick and oil fill cap.
4. Record the vehicle mileage.
5. Instruct the customer to drive the vehicle as
usual.
6. Ask the customer to return to the servicing
dealer after accumulating 800 km., Check the oil
level at least 15 minutes after a hot shut down. If
the oil level is half way between the "FULL" and
"ADD" mark continue with the next step.
7. Using a black light, re-check for any external
engine oil leaks, repair as necessary, if no
external engine oil leaks are present, continue
with oil consumption diagnosis.
OIL CONSUMPTION DIAGNOSIS
1. Perform a cylinder compression test and
cylinder leak down test using the standard leak
down gauge following manufacturers suggested
best practices.
2. If one or more cylinders have more than 15%
leak down further engine tear down and
inspection will be required.
3. If the compression is good it can be assumed
the valve guide seals or valve guides are at fault.
TOP 18 REASONS THAT MAY LEAD TO
ENGINE OIL CONSUMPTION
1.
Tapered and Out-of-Round Cylinders
The increased piston clearances permit the
pistons to rock in the worn cylinders. While tilted
momentarily, an abnormally large volume of oil is
permitted to enter on one side of the piston. The
rings, also tilted in the cylinder, permit oil to enter
on one side. Upon reversal of the piston on each
stroke, some of this oil is passed into the
combustion chamber.
2.
Distorted Cylinders
This may be caused by unequal heat distribution
or unequal tightening of cylinder head bolts. This
condition presents a surface which the rings may
not be able to follow completely. In this case,
there may be areas where the rings will not
remove all of the excess oil. When combustion
takes place, this oil will be burned and cause high
oil consumption.
3.
Improper operation of "Closed Crankcase
Ventilation (CCV)" system
The main purpose of the Closed Crankcase
Ventilation (CCV) is to recirculate blow-by gases
back from the crankcase area through the engine
to consume unburned hydrocarbons. The system
uses a filter, tubing, and rubber hoses that route
crankcase blow by gases to the intake manifold.
Vacuum within the engine intake manifold pulls
the blow by gases out of the crankcase into the
combustion chamber along with the regular intake
air and fuel mixture.
The CCV system can become clogged with
sludge and varnish deposits and trap blow by