Hobart 120CU20, Operation And Maintenance Manual With Illustrated Parts List

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OM-2228 / Operation and Maintenance Manual
120CU20 / Series 500120 / 400 Hz. Generator Set
October 15, 2013 Chapter 2-2
Page 11
b) Radiator Cap.
(1) General.
A pressure relief valve is built into the radiator cap. It is designed to open at a pressure of
approximately 15 psi (103.4 Kpa).
WARNING
When removing cap from a very hot radiator, do not turn cap past safety stop until the
pressure or steam has escaped.
(2) Removal.
To remove, turn the cap to the left (counterclockwise) to the safety stop. When all pressure is
released, press down on the cap and continue to turn until the cap is free to be removed.
CAUTION
Allow engine to cool before adding coolant.
CAUTION
Do not attempt to repair the valve in a radiator cap in case of failure. Replace with a
new cap.
(3) Installation.
When installing the cap, be sure it is turned clockwise as far as it will go so that the pressure-
retaining valve will be functional.
c) Coolant.
The preparation and maintenance of the coolant solution is important to engine life and is completely
covered in the engine manufacturer’s operation manual. For information regarding coolant
specifications, testing equipment, antifreeze, etc., refer to engine manufacturer’s operation manual
that accompanies the equipment manufacturer’s manual or consult the local engine manufacturer’s
representative.
CAUTION
Never use soluble oil in the cooling system.
(1) General.
A permanent type antifreeze is recommended for use in the cooling system.
CAUTION
1. DO NOT use methanol or alcohol as antifreeze.
2.
DO NOT mix brands or type of antifreeze. A solution containing two or more types
of antifreeze is impossible to test accurately.