Preventive Maintenance
Item 5
Inspect the exterior of the radiator core every 1,000 hours or 30,000 miles and, if necessary, clean it with a quality grease
solvent such as mineral spirits and compressed air. Do not use fuel oil, kerosene or gasoline. It may be necessary to
clean the radiator more frequently if the engine is being operated in extremely dusty or dirty areas.
Item 6
Every 500 hours drain the water from the heat exchanger raw water inlet and outlet tubes. Then remove the zinc
electrodes from the inlet side of the raw water pump and the heat exchanger. Clean the electrodes with a wire brush or,
if worn excessively, replace with new electrodes. To determine the condition of a used electrode, strike it sharply against
a hard surface; a weakened electrode will break.
Drain the cooling system, disconnect the raw water pipes at the outlet side of the heat exchanger and remove the
retaining cover every 1,000 hours and inspect the heat exchanger core. If a considerable amount of scale or deposits
are present, contact an authorized Detroit Diesel Allison Service Outlet.
Item 7
Check the prime on the raw water pump; the engine should
not be operated with a dry pump. Prime the pump, if
necessary, by removing the pipe plug provided in the pump
Item 5
inlet elbow and adding water. Reinstall the plug.
Item 8
Keep the fuel tank filled to reduce condensation to a
minimum. Select the proper grade of fuel in accordance
with the Diesel Fuel Oil Specifications.
Open the drain at the bottom of the fuel tank every 500
hours or 15,000 miles to drain off any water or sediment.
Item 9
Install new elements every 300 hours or 9,000 miles or
when plugging is indicated. A method of determining when
elements are plugged to the extent that they should be
changed is based on he fuel pressure at the cylinder head
fuel inlet manifold and the inlet restriction at the fuel pump.
Item 6
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