
120 31200243
Maintenance Section
Cooling System Pressure Cap
- Clean/Replace
Personal injury can result from hot coolant, steam and
alkali.
At operating temperature, engine coolant is hot and
under pressure. The radiator and all lines to heaters
or the engine contain hot coolant or steam. Any
contact can cause severe burns.
Remove filler cap slowly to relieve pressure only when
engine is stopped and radiator cap is cool enough to
touch with your bare hand.
Do not attempt to tighten hose connections when the
coolant is hot, the hose can come off causing burns.
Illustration 223 g01081068
The cooling system pressure cap is located on the coolant
tank inside the engine compartment.
1. Remove the cap slowly in order to relieve the
pressure.
2. Inspect the cap and the gasket for damage, for
foreign material, and for deposits.
3. Clean the cap with a clean cloth or replace the cap
if it is necessary.
Note: Always check the pressure rating of the old cap
before you replace the cap. Replace the old cap with a
new cap of the same pressure rating.
4. Reinstall the cap.
Cooling System Water
Temperature Regulator
Replace
Personal injury can result from hot coolant, steam and
alkali.
At operating temperature, engine coolant is hot and
under pressure. The radiator and all lines to heaters
or the engine contain hot coolant or steam. Any
contact can cause severe burns.
Remove filler cap slowly to relieve pressure only when
engine is stopped and radiator cap is cool enough to
touch with your bare hand.
Do not attempt to tighten hose connections when the
coolant is hot, the hose can come off causing burns.
NOTICE
Care must be taken to ensure that fluids are contained
during performance of inspection, maintenance, testing,
adjusting and repair of the product. Be prepared to collect
the fluid with suitable containers before opening any
compartment or disassembling any component
containing fluids.
Refer to Special Publication, NENG2500, "Caterpillar
Dealer Service Tool Catalog" for tools and supplies
suitable to collect and contain fluids on Caterpillar
products.
Dispose of all fluids according to local regulations and
mandates.
NOTICE
Failure to replace the engine's water temperature
regulator on a regularly scheduled basis could cause
severe engine damage.
NOTICE
Since Caterpillar engines incorporate a shunt design
cooling system, it is mandatory to always operate the
engine with a water temperature regulator.
Depending on load, failure to operate with a water
temperature regulator could result in either an
overheating or an overcooling condition.
Replace the water temperature regulator on a regular
basis in order to reduce the chance of unscheduled
downtime and of problems with the cooling system.
The water temperature regulator should also be
replaced after the cooling system has been cleaned.
Replace the water temperature regulator while the
cooling system is completely drained or while the