freightliner S2 Operator's Manual page 24

for easier viewing, the intake-air restriction indicator
can be mounted on the dash, usually on the right-
hand control panel.
10/10/2001
Fig. 3.15, Air Intake Restriction Indicator
Air intake restriction vacuum is measured in inches
of water (inH O). For vehicles equipped with a gradu-
2
ated indicator or a restriction gauge on the dash,
check the gauge with the engine off. If the yellow
signal stays locked in the red zone once the engine
is shut down, or is at or above 25 inH
cleaner element needs to be replaced.
NOTE: Rain or snow can wet the filter and
cause a temporarily higher than normal reading.
Ammeter
An optional ammeter measures current flowing to
and from the battery. See
ies are being charged, the meter needle moves to
the plus side of the gauge; when the batteries are
being discharged, the needle moves to the minus
side. A consistent negative reading when the engine
is running indicates a possible problem with the
charging system.
f610568
O, the air
2
Fig. 3.16. When the batter-
10/10/2001
Fig. 3.16, Ammeter
Axle Oil Temperature Gauge, Rear
NOTICE
A sudden increase in oil temperature that is not
caused by a load increase may indicate mechani-
cal failure. Bring the vehicle to a safe stop and
investigate the cause to prevent further damage.
Do not operate the vehicle until the cause has
been determined and corrected.
During normal operation, the optional rear axle oil
temperature gauge should read between 160 and
220°F (71 and 104°C) for Detroit
axles. See Fig. 3.17.
10/10/2001
Fig. 3.17, Axle Oil Temperature Gauge
Instruments
f610573
™ ™
and Meritor drive
f610571
3.12