Inspect the radiator cap for damage. The sealing
surface must be dean.
Look for large amounts of dirt in the radiator core. Look
for large amounts of dirt on the engine.
Shrouds that are loose or missing cause poor air flow
Testing The Cooling System
Remember that temperature and pressure work together. Both
the temperature and the pressure must be checked when a
problem with the cooling system exists. The pressure of the
cooling system will have an effect on the temperature of the
cooling system. Review Illustration 78 in order to determine
the following effects on the boiling point of water:
height above sea level
Cooling system pressure at specific altitudes and boiling points of
Test Tools For The Cooling System
Digital Thermometer Group
Blowby/Air Flow Indicator
4C-6500 Digital Thermometer Group.
The 4C-6500 Digital Thermometer Group is used in the
diagnosis of problems that cause overheating or overcooling in
the engine. This tool can be used to check the temperature in
several areas of the cooling system. The testing procedure is
in Tool Operating Manual, NEHS0554.
8T-2700 Blowby/Air Flow Indicator Group.
The 8T-2700 Blowby/Air Flow Indicator Group is used to check
the air flow through the radiator core. The operating
instructions are included with the tooling.