Surtek 107369 Manual De Usuario Y Garantía página 8

E N G L I S H
WHAT IS TIMING?
The special "Xenón" bulb used in these lights
will provide the ultrabright flash needed to see
engine timing marks under most bright lighting
conditions, even during normal daylight.
In order for an automobile engine to function,
three things are necessary: air, fuel and a spark
to ignite the air/fuel mixture and create an
explosion.
The precise instant of that explosion must be
such that the maximum power is delivered to
the engine piston, this is "Timing." Each engine
manufacturer determines at the factory the
exact timing necessary for various engines so
that each ounce of power is obtained from every
gallon of fuel.
Due to normal engine and ignition system wear,
the timing can change and will reduce both
power and mileage. With the Xenón timing
light, the car owner can reset the timing to the
new car standards and regain lost power and
increase mileage.
Timing is given in degrees Before Top Dead
Center (BTDC) or After Top Dead Center (ATDC)
in the manufacturer's specifications. In order to
completely burn the air/fuel mixture in the car's
engine cylinders, most timing is such that the
spark occurs at a point several degrees before
top dead center (for example, 4° BTDC) to assure
that full power of the explosion is obtained. See
Figure 1.
Manufacturers use
describing the synchronize, these are advanced
and delayed.
Two additional terms the engine manufacturers
use when describing timing are "Advanced" and
"Retarded". As shown in Figure 1, when the
timing is advanced the spark will occur before
the piston reaches the top of the engine cylinder
(BTDC).
On some late model cars equipped with various
emission control devices, the timing is retarded
so that the spark occurs after the piston has
started down in the cylinder (ATDC).
8
two additional terms
Engine timing is changed by adjustment of the
ignition distributor.
In order to allow setting and adjustment of
the engine timing, special 'Timing Marks" are
provided on each engine during assembly. In
most cases, these marks appear on the engine
vibration damper or fan pulley at the lower front
of the engine. See Figure 1.
On some early engines, this mark was shown at
the rear of the engine on the flywheel.
ENGINE TIMING SETTINGS
FIGURE 1.
WHEN TO CHECK TIMING
The instant of spark plug firing is determined by
the opening of the distributor ignition breaker
points and will change any time the point gap
or DweII angle is changed. In addition, normal
wear on the breaker point rubbing block will
change the dwell and affect the timing.
While cars equipped with the new "breakerless
Electronic Ignition Systems" will not normally
change timing since there are no breaker points,
the timing light can still be used to note changes
in timing caused by troubles in the ignition
system as well as for resetting timing when
components are changed.
TIMING SPECIFICATIONS