Hitachi Zaxis 17U-5A Operator's Manual page 59

 Hot coolant or oil may spout if the radiator or hydraulic
oil cap is removed while the machine temperature is still
high, possibly causing a burn. Wait until the machine has
cooled to remove the cap.
ZX17U-5A
SS4392290-1
SAFETY SIGNS
SS4420336-2
ZX26U-5A
S-47
MABA-00-024
ZX17U-5A
ZX17U-5A MABA-00-025
MABA-00-026
ZX26U-5A
MABA-00-027
ZX26U-5A