VALVE & MTG GP-DIFF LOCK 7T9073 - Caterpillar

systems that are not regularly inspected can be the cause for increased engine temperatures. Make a visual inspection of the cooling system before a test is made with test equipment.
Check the coolant level in the cooling system. Read the two indicators for the coolant level in the top of the radiator.
Look for leaks in the system.
Look for bent core fins or trash between the folded cores of the radiator. Be sure that air flow through the radiator does not have a restriction.
Check for damage to the fan blades.
Personal injury can result from escaping fluid under pressure.If a pressure indication is shown on the indicator, push the release valve in order to relieve pressure before removing any hose from the radiator.
After the engine is cool, remove the filler cap slowly. This will allow any pressure out of the cooling system. Inspect the filler cap and the surface that seals the cap. This surface must be clean and the seal must not be damaged.
Check the pressure relief valve. Relief pressure of the valve is 105 to 125 kPa (15 to 18 psi).
Look for air or combustion gas in the cooling system.