OM-C3 11/21
45
7. Close all drain valves after coolant has drained.
Do not run engine longer than 10 minutes. Doing so
may cause engine to overheat, causing burns when
cooling system is draining.
8. Fill the cooling system with clean water. Run the
engine about 10 minutes to stir up possible rust or
sediment.
9. Stop engine, pull off lower cooling system hose and
remove heat exchanger or top tank cap. Immediately
drain the water from system before rust and sediment
settle.
10. After draining water, close drain valves. Reinstall cap,
lower cooling system hose and clamp. Fill the cooling
system with clean water and a heavy duty cooling
system cleaner such as Fleetguard® RESTORE™
and RESTORE PLUS™.
11. After cleaning the cooling system, drain cleaner and
fill with water to flush the system. Run the engine about
ten minutes, remove heat exchanger or top tank cap and
pull off lower cooling system hose to drain out flushing
water.
12. Close all drain valves. Reinstall hoses and tighten
clamps securely. Install thermostats using a new gasket.
SP 23. Checking Engine Electrical Ground
Connections
Keep all engine ground connections clean and tight to
prevent electrical arcing which can damage electronic
components.
SP 22. Flushing and Refilling Cooling System
Explosive release of fluids from
pressurized cooling system can
cause serious burns. Shut off
engine. Only remove filler cap
when cool enough to touch with
bare hands. Slowly loosen cap to
first stop to relieve pressure before removing
completely.
Drain old coolant, flush the entire cooling system, test
thermostats (page 50), and fill with recommended clean
coolant using the following procedure.
1. Pressure test entire cooling system and pressure cap if
not previously done. (See PRESSURE TESTING
COOLING SYSTEM, on page 44.)
2. Slowly open the cap on the top tank (A, below) or heat
exchanger to relieve pressure and allow coolant to drain
faster.
3. Open engine block drain valve (A) on left side of
engine. Drain all coolant from engine block.
4. Open heat exchanger or top tank drain valve. Drain all
coolant from heat exchanger or top tank.
5. Remove thermostats at this time, if not previously
done. Install cover (without thermostats) using old
gasket and tighten cap screws to 47 N·m (35 lb-ft).
6. Test thermostat opening temperature. (See Inspecting
Thermostats And Testing Opening Temperature
on Pages 49-50).
Service and Maintenance - 500 Hour
!
CAUTION
!
CAUTION
Engine block drain valve (A)
