'00 AVALON U (L/O9908)
233
FUNCTIONS OF ENGINE OIL
Engine oil has the primary functions of
lubricating and cooling the inside of the
engine, and plays a major role in main-
taining the engine in proper working order.
ENGINE OIL CONSUMPTION
It is normal that an engine should con-
sume some engine oil during normal
engine operation. The causes of oil
consumption in a normal engine are as
follows.
Oil is used to lubricate pistons, piston
rings and cylinders. A thin film of oil
is left on the cylinder wall when a pis-
ton moves downwards in the cylinder.
High negative pressure generated when
the vehicle is decelerating sucks some
of this oil into the combustion chamber.
This oil as well as some part of the oil
film left on the cylinder wall is burned
by the high temperature combustion
gases during the combustion process.
Oil is also used to lubricate the stems
of the intake valves. Some of this oil
is sucked into the combustion chamber
together with the intake air and is
burned along with the fuel. High tem-
perature exhaust gases also burn the
oil used to lubricate the exhaust valve
stems.
The amount of engine oil consumed de-
pends on the viscosity of the oil, the
quality of the oil and the conditions the
vehicle is driven under.
More oil is consumed by high- speed driv-
ing and frequent acceleration and decel-
eration.
A new engine consumes more oil, since
its pistons, piston rings and cylinder walls
have not become conditioned.
When judging the amount of oil con-
sumption, note the that oil may become
diluted and make it difficult to judge
the true level accurately.
As an example, if a vehicle is used for
repeated short trips, and consumes a nor-
mal amount of oil, the dipstick may not
show any drop in the oil level at all, even
after 1000 km (600 miles) or more. This
is because the oil is gradually becoming
diluted with fuel or moisture, making it
appear that the oil level has not changed. The diluting ingredients evaporate out
when the vehicle is then driven at high
speeds, as on an expressway, making it
appear that oil is excessively consumed
after driving at high speeds.
IMPORTANCE OF ENGINE OIL LEVEL
CHECK
One of the most important points in prop-
er vehicle maintenance is to keep the en-
gine oil at the optimum level so that oil
function will not be impaired. Therefore, it
is essential that the oil level be checked
regularly. Toyota recommends that the oil
level be checked every time you refuel
the vehicle.
NOTICE
Failure to check the oil level regularly
could lead to serious engine troubledue to insufficient oil.
For detailed information on oil level check,
see Checking the engine oil levelº in Sec-
tion 7- 2.
Facts about engine oil
consumption
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'00 AVALON U (L/O9908)
289
INSIDE THE VEHICLE
Items listed below should be checked
regularly, e.g. while performing periodic
services, cleaning the vehicle, etc.
Lights
Make sure the headlights, stop lights, tail
lights, turn signal lights, and other lights
are all working. Check headlight aim.
Service reminder indicators and warning
buzzers
Check that all service reminder indicators
and warning buzzers function properly.
Steering wheel
Check that it has the specified free play.
Be alert for changes in steering condition,
such as hard steering or strange noise.
Seats
Check that all front seat controls such as
seat adjusters, seatback recliner, etc. op-
erate smoothly and that all latches lock
securely in any position. Check that the
head restraints move up and down
smoothly and that the locks hold securely
in any latched position.
Seat belts
Check that the seat belt system such as
buckles, retractors and anchors operate
properly and smoothly. Make sure the belt
webbing is not cut, frayed, worn or dam-
aged.Accelerator pedal
Check the pedal for smooth operation and
uneven pedal effort or catching.
Brake pedal
Check the pedal for smooth operation and
that the pedal has the proper clearance.
Check the brake booster function.
Brakes
At a safe place, check that the brakes do
not pull to one side when applied.
Parking brake
Check that the pedal has the proper travel
and that, on a safe incline, your vehicle
is held securely with only the parking
brake applied.
Automatic transmission Parkº mecha-
nism
Check the lock release button of the se-
lector lever for proper and smooth opera-
tion. On a safe incline, check that your
vehicle is held securely with the selector
lever in Pº position and all brakes re-
leased.
IN THE ENGINE COMPARTMENT
Items listed below should be checked
from time to time, e.g. each time when
refueling.
Washer fluid
Make sure there is sufficient fluid in the
tank. See Section 7- 3 for additional infor-
mation.
Engine coolant level
Make sure the coolant level is between
the FULLº and LOWº lines on the see-
through reservoir when the engine is cold.
See Section 7- 2 for additional information.
Battery electrolyte level
Make sure the electrolyte level of all bat-
tery cells is between upper and lower lev-
el lines on the case. Add only distilled
water when replenishing. See Section 7- 3
for additional information.
Brake fluid level
Make sure the brake fluid level is correct.
See Section 7- 2 for additional information.
Engine oil level
Check the level on the dipstick with the
engine turned off and the vehicle parked
on a level spot. See Section 7- 2 for addi-
tional information.
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