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 2-1
Page 7
(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 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.
b 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.
c Check Radiator Core and Hoses
Inspect the radiator core for dirt and debris blocking the fins. Clean as necessary. Check for
cracks, holes, or other damage.
d Check Fuel Pump
Inspect the fuel injection pump mounting nuts for loose are damaged hardware.
(2) Electrical (12 VDC system)
NOTE: The battery furnished with this generator set is MAINTENANCE FREE.
Check battery terminals and clean if necessary.
(3) Electrical (400 Hz System)
a Check the operation of the E-F bypass system.