Transmitter Calibration; Hourmeter; Magnetic Compass - Cessna 150 STANDARD Service Manual

7
THRU 15073691, A1500339,
F15000863 AND FA1500166
1. Fuselage Structure
2. Nutplate
3. Compass Mount
4. Lower Cover
5. Compass
6. Correction Card
7. Cover
8. Compass Cover
9. Windshield
Figure 15-6.
15-43. TRANSMITTER CALIBRATION. Chances of
transmitter calibration changing in normal service
is remote, however, it is possible that float arm or
float arm stops may become bent if transmitter is
removed from tank. Transmitter calibration is ob-
tained by adjusting float travel. Float travel is
limited by float arm stops.
IWARNING'
Use extreme caution while working with electri-
cal components of fuel system. The possi-
bility of electrical sparks around an "empty"
fuel tank creates a hazardous situation.
8
Before installing transmitter, attach electrical wires
and place master switch in "ON" position. Allow
float arm to rest against lower float arm stop and
read indicator. The pointer should be on E (empty)
position. Adjust lower stop with float arm against
stop so that pointer indicator is on E (empty). Raise
float until arm is against upper stop and adjust stop
to permit indicator pointer to be on F (full). Install
NOTE
*
Torque compass mount screw
10-15 lb inches to prevent
rotation in flight.
'.----6
BEGINNING WITH 15073692, A1500340,
F15000864 AND FA1500167
Magnetic Compass
transmitter in accordance with Section 12.
15-44. HOURMETER.
15-45. DESCRIPTION. The hourmeter is electri-
cally operated and is actuated by a pressure switch in
the oil pressure gage line. Electrical power is sup-
plied through a one-amp fuse from the electrical
clock circuit and therefore, will operate indepen-
dent of the master switch.
15-46. MAGNETIC COMPASS. (Refer to figure
15-6. )
15-47. DESCRIPTION. The magnetic compass is
liquid-filled, with expansion provisions to compen-
sate for temperature changes.
It
is equipped with
compensating magnets adjustable from front of case.
The compass is internally lighted, controlled by the
panel lights rheostat. No maintenance is required
on compass except on occasional check on a com-
pass rose for adjustment of compensation and re-
placement of lamp.
Change 1 15-17