JLG G6-42P Service Manual - Manual (Page 133)

FLUSH AND SERVICE COOLING SYSTEM
IMPORTANT: CAUTION: Explosive release of fluids form
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 cap completely.
IMPORTANT: Air must be expelled from cooling system
when system is refilled. Follow procedure
given in your operator’s manual.
The ethylene glycol base, (antifreeze), can become
depleted of SCAs allowing various acids to form that
will damage engine components. In addition, heavy
metals, such as lead, copper and zinc accumulate in
the ethylene glycol base. The heavy metals come from
corrosion that occurs to some degree within a cooling
system. When a coolant is saturated to the point where
it can no longer hold heavy metals and other dissolved
solids, they settle out and act as abrasives on engine
parts.
NOTE: Refer to your operator’s manual for a specific
service interval.
Flush cooling system and replace thermostats as
described in your operator’s manual. Clean cooling
system with clean water and TY15979 John Deere
Heavy-Duty Cooling System Cleaner or an equivalent
cleaner such as FLEETGUARD RESTORE or RE-
STORE PLUS. Follow the instructions provided with
the cleaner. Refill the cooling system with the appropri-
ate coolant solution. See ENGINE COOLANT SPECI-
FICATIONS, earlier in this group.
IMPORTANT: NEVER overfill the system. A pressurized
system needs space for heat expansion
without overflowing at the top of the radiator.
Coolant level should be at tbottom of radiator
filler neck.
Air must be expelled from cooling system
when the system is refilled. Loosen tempera
ture sending unit fitting at rear of cylinder
head or plug in thermostat housing to allow
air to escape when filling system. Re-tighten
fitting or plug when all the air has been
expelled.
After adding new coolant solution, run engine until it
reaches operating temperature. This mixes the coolant
solution uniformly and circulates it through the entire
system. After running engine, check coolant level and
entire cooling system for leaks.
Contact your authorized servicing dealer or engine
distributor if there are further questions.
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