Engine Is Overheating - Peterbilt 579 Operator's Manual

6. Wait a few minutes to allow oil to
drain into the engine oil pan, and
then check the oil level. (See Oil
Level Check on page 5-93, for
details on checking oil level.)
7. Add oil if necessary. If the problem
persists, contact an authorized
dealer as soon as possible.
CAUTION
Continuing to operate your vehicle
with insufficient oil pressure may
cause severe engine damage or
cause an accident which may result in
equipment or property damage.
It is important to maintain oil pressure
within acceptable limits. If oil pressure
drops below the minimum psi (kPa) a
Red Warning Lamp on the oil pressure
gauge will illuminate and the Stop
Engine Lamp will come ON.
(04/13)

Engine is Overheating

The cooling system may overheat if
the coolant level is below normal or if
there is sudden loss of coolant, such
as a split hose. The system may also
temporarily overheat during severe
operating conditions such as:
•
Climbing a long hill on a hot day
•
Stopping after high-speed driving
If either one of the above occurs, DO
NOT TURN OFF THE ENGINE unless:
a) the Low Water warning device
indicates a loss of coolant, b) the Red
Warning lamp (on the gauge) and
Check Engine lamp comes ON, c) the
Buzzer sounds showing an overheat
condition, or d) if you have any other
reason to suspect the engine may be
overheating - follow these steps.
1. Reduce engine speed and
stop. When stopped, place the
transmission in Neutral and set the
Y53-6047–2C
WHAT TO DO IF...
parking brake. (See Parking Brake
Valve on page 4-22 and Putting
the Vehicle in Motion on page
4-15, for transmission shifting and
parking brake information.) Keep
the engine running.
2. Check to ensure the Oil Pressure
Gauge reads normal. (See Engine
Oil Pressure Gauge on page 3-11,
for further information.)
3. Make sure the engine fan is
turning by switching the Engine
Fan Switch from AUTO to MAN
(Manual).
4. Increase the engine speed to
about one-half of full operating
speed, or 1,100 to 1,200 rpm,
maximum.
5. Return the engine speed to normal
idle after 2 or 3 minutes.
6. Monitor the engine temperature.
After the temperature returns to
normal, allow the engine to idle
2
2-5