105
FUNCTIONS OF ENGINE OIL
Engine oil has the primary functions of lu-
bricating and cooling the inside of the en-
gine,
and plays a major role in maintaining
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 piston
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 com-
bustion gases during the combustionprocess.
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
depends 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 that the oil may be-come diluted and make it difficult to
judge the true level accurately.
As an example, if a vehicle is used for re-
peated 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 ap-
pear 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 itappear that oil is excessively consumed
after driving as high speeds.
IMPORTANCE OF ENGINE OIL LEVEL CHECK
One of the most important points in proper vehicle maintenance is to keep the engine
oil at the optimum level so that oil function
will
not be impaired. Therefore, it is essen-
tial that the oil level be checked regularly.
Toyota recommends that the oil level bechecked every time you refuel the vehicle.
Failure to check the oil level
regularly could lead to serious
engine trouble due to insufficientoil.
NOTICE
For detailed information on the oil level
check, see Checking the engine oil levelº
in Chapter 7-2.
Facts about engine oil consumption
143
Tire surface and wheel nuts Check the tires carefully
for cuts, damage
or excessive wear. See Chapter 7-2 for
additional information. When checking the tires, make sure no nuts are missing,
and check the nuts for looseness. T ighten
them if necessary.
Tire rotation
Rotate the tires every 12000 km (7500
miles). See Chapter 7-2 for additional in- formation.
Fluid leaks Check underneath for leaking fuel, oil, wa-
ter or other fluid after the vehicle has been
parked for a while. If you smell fuel fumes
or notice any leak, have the cause found
and corrected immediately. Doors and engine hood Check that all doors including trunk lid op-
erate smoothly and all latches lock se-
curely. M ake sure the engine hood secon-
dary latch secures the hood from opening
when the primary latch is released. INSIDE THE VEHICLE Items listed below should be checked
regularly, e.g. while performing peri-
odic 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
warn-
ing buzzers Check that all service reminder indicators
and warning buzzers function properly. Steering wheel
Check that it has the specified freeplay.
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. For folding-down
rear seat backs, check that the latches
lock securely. 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. Clutch pedal Check the pedal for smooth operation. Brake pedalCheck 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 lever has the proper travel and that, on a safe incline, your vehicle is
held securely with only the parking brake applied.
152Here is a list of parts and tools you will
need on performing do-it-yourself main-
tenance. Remember all Toyota parts are
designed in metric sizes, so your tools
must be metric. Checking the engine oil level Parts (if level is low):
Engine oil API SH, Energy-Conserv-
ing IIº multigrade or ILSAC multigrade
having viscosity proper for your cli-mate
Tools: Rag or paper towel
Funnel (only for adding oil)
Checking the engine coolant level Parts (if level is low): Ethylene-glycol antifreeze
Demineralized or distilled water
Tools: Funnel (only for adding coolant)
Checking brake fluid Parts (if level is low): SAE J1703 or FMVSS No. 116 DOT 3 brake fluid Tools:
Rag or paper towel
Funnel (only for adding fluid)
Checking power steering fluid Parts (if level is low): Automatic transmission fluid DEX- RON [
II or III
Tools: Rag or paper towel
Funnel (only for adding fluid)
Checking battery condition Non-maintenance batteriesÐ
Tools: Warm water
Baking soda
Grease
Conventional wrench (for terminal clamp bolts)
Maintenance type batteriesÐ Parts (if level is low): Distilled water Tools:
Warm water
Baking soda
Grease
Conventional wrench (for terminal clamp bolts)
Coin (for vent plugs)
Funnel (only for adding distilled water)
Checking and replacing fuses Parts (if replacement is necessary): Fuse with same amperage rating as original
Tools: Conventional wrench (for instrument
lower panel nut)
Adding washer fluid Parts: Water
Washer fluid containing antifreeze (for winter use)
Parts and tools