Owners Manual

BYD AUTO F3 OWNER’S MANUAL
118
Facts about engine oil consumption
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 maintaining the engine in proper
working order.
Engine oil consumption
It is normal that an engine should
consume 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
sucks some of this oil into the
combustion chamber when the
vehicle is decelerating. This oil
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
temperature 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
driving and frequent acceleration and
deceleration.
A new engine consumes more oil,
since its pistons, piston rings and
cylinder walls have not become
conditioned.
Oil consumption:
Max. 1.0 L/1,000 km
When judging oil consumption, pay
attention to that it would be
difficult to judge the real oil level
because oil rarefies.
For example, if vehicle repeatedly
drives for a short distance, oil would
be consumed. In this case, even if the
vehicle drives for 1,000 km or above,
oil level displayed on oil dip rod
would not decrease since oil has been
rarefied by fuel and smoke.
If vehicle drives at high speed (e.g.
on freeway), rarefied oil would ablate,
so oil will be over-consumed after
high speed driving.