Charge-Air-Cooler (Cac) And Piping - Hobart 60CU20 Operation And Maintenance Manual With Illustrated Parts List

OM-2226 / Operation and Maintenance Manual
60CU20 / Series 500062 / 400 Hz. Generator Set
(3) Electrical (400 Hz System)
b Check Output Cables and Connector
Check the output cable and plug connection for damaged insulation and contacts each time
the connector is detached from the aircraft.
b Monitoring Instruments
Check operation of voltmeter, ammeter and frequency meter each time the unit is started.
e) "B" Check and Operations (250 Hours or 3 Months)
(1) Engine
a Prevent Diesel Engines Wet Stacking
All diesel engines operated for extended periods under light load may develop a condition
commonly referred to as wet-stacking. This condition results from the accumulation of
unburned fuel in the exhaust system. It is recognizable by fuel oil wetness around the
exhaust manifold, pipes, and muffler along with an excessive amount of soot.
Wet-stacking is common, and can be expected in diesel engines operated under light loads.
Light loads do not allow the engine to reach the most efficient operating temperature for
complete combustion of fuel and will also increase the fuel consumption rate. The unburned
fuel collects in the exhaust system to create the wet condition known as wet-stacking.
To alleviate wet-stacking in lightly loaded engines, it is recommended that the machine be
connected to a load bank after each 250 hours of use and operated under full rated load for
one hour. This will burn away and evaporate the accumulation of fuel and soot in the exhaust
system. This clean-out procedure should be considered as a regular maintenance operation
for machines operated under light loads.
b Charge-Air-Cooler and Piping
Inspect the charge-air-cooler for dirt and debris blocking the fins. Check for cracks, holes, or
other damage.
Inspect the pipes and hoses for leaks, holes, cracks, or loose connections. Tighten the hose
clamps if necessary.
c Check and record oil pressure
After each oil change, check and record oil pressure at idle speed after oil has warmed to
approximately 140º F. Record oil pressure under identical conditions at each oil change
interval. A comparison of pressure at idle speed with previous readings will give an indication
of progressive wear of oil pump, bearings, shafts, etc. Investigate any abnormal change in
pressure readings.
May 2, 2013 Chapter 2-1
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