Honda ES6500 Owner's Manual page 25

If there is no coolant in the reserve tank:
Make sure the engine is cool, then check the coolant system for leaks
and have repairs made if needed. Add coolant to the reserve tank
before starting the engine.
B
Hot coolant is under pressure. If you remove the radiator cap when
the engine is hot, you may be scalded. Wait for the engine to cool.
1. When the engine is cool, relieve any remaining coolant pressure by
turning the radiator ca counterclockwise until it reaches its stop'
DO NOT PRESS DOWN WHILE TURNING THE CAP. After ali
pressure has been relieved, press the cap down, and continue
turning the cap to remove it.
RADIATOR
2.Fill the radiator with coolant, and reinstall the radiator cap. Tighten
the cap securely.
3. Fill the reserve tank to the MAX mark with coolant.
Antifreeze/Coolant Recommendation
Use high quality ethylene
for aluminum engines.
d
lycol coolant that is specifically formulated
water or distilled water,
ix the coolant with low-mineral drinking
A 50/50 mixture of ethylene glycol coolant and water is recommended
for most temperatures, and it provides good corrosion protection. A
higher concentration of coolant decreases cooling efficiency and is
recommended if additional protection against freezing is needed. A
concentration of less than 40% antifreeze will not provide enough
corrosion protection.
(J
The wron type of coolant, hard water, or salt water can cause
corrosion
d amage in the engine.
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