Doosan DX700LC Operation And Maintenance Manual page 187

Operation at High Altitudes
Normally, operation of machine at high altitudes will be as
outlined in extreme cold. Before operating at high altitudes,
engine fuel and air mixture may have to be adjusted according
to appropriate engine manual.
1. Check engine operating temperature for evidence of
overheating. The pressure cap on radiator must make a
perfect seal to maintain coolant pressure in the system.
Operation OP001122
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