JUL 2020 Chapter 95 Instrument System Page 95.21
95-44 Hourmeters
A. Description
Two hourmeters are standard. One hourmeter is mounted above the ammeter and
is activated by main gearbox oil pressure. Another hourmeter on the horizontal
panel outboard of the pilot’s seat is activated by a combination of main gearbox oil
pressure and a raised collective and is approved for recording time in service.
B. Schematic
Refer to Figure 98-1 for electrical schematic.
C. Removal
Collective-Activated Hourmeter
1. Remove screws securing hourmeter, faceplate, and carpet to F353-2 panel.
2. Disconnect airframe wiring from hourmeter wiring at connectors, and remove
hourmeter.
Console Hourmeter
1. Remove screws securing hourmeter to F640 face assembly, remove screws
securing face to lower console, and supporting hourmeter, remove face.
2. Disconnect airframe wiring from hourmeter, and remove hourmeter.
D. Installation
Collective-Activated Hourmeter
1. Connect airframe wiring to hourmeter wiring at connectors. Verify security.
2. Install screws securing hourmeter, faceplate, and carpet to F353-2 panel. Verify
security.
Console Hourmeter
1. Connect airframe wiring to hourmeter (F859-2053 to positive terminal). Verify
security.
2. Install screws securing F640 face assembly to lower console. Install screws
securing hourmeter to face. Verify security.
E. Scheduled Maintenance and Inspections
On condition.
F. Special Maintenance and Inspections
1. Inspect wiring for loose, chafed, frayed, or broken wires. Verify no damaged
connectors. Verify wiring neatness, proper routing and installation, and security.
2. If hourmeter is still inoperative, remove hourmeter per Part C, and install airworthy
hourmeter per Part D. Make appropriate maintenance record entries.
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