Piper Arrow IV Turbo Maintenance Manual page 683

BENCH TEST.
1. After the starting motor is reassembled, it should be tested to see that the no-load current at a certain
voltage is within specifications as given in Starting Motor Service Test Specifications. To make this test,
connect as shown in Figure 80-5. If current is too high, check the bearing alignment and end play to make sure
there is no binding or interference. Two or three sharp raps on the frame with a rawhide hammer will often
help to align the bearings and free the armature.
2. If no difficulty is indicated in the above test, a stall torque test may be made to see if the starting motor
is producing its rated cranking power. Make test connections as shown in Figure 80-6.
3. If torque and current are not within specifications, check the seating of the brushes and internal
connections for high resistance. If these checks are made and found to be in good order, replace frame and
field assembly and retest starter.
STARTING MOTOR CONTROL CIRCUIT.
1. Inspect the control circuit wiring between the battery, solenoid and manual starting switches for
breaks, poor connections and faulty insulation. Tighten all connections and make sure solenoid is firmly
mounted and makes a good ground connection.
2. Check the voltage loss across the switch contacts during normal starting. If loss is in excess of 0.2-
volts per 100 amperes, the solenoid should be replaced.
3. If solenoid fails to operate when the manual starting switch is turned on or if it fails to release when
the manual starting switch is released, it should be removed and tested to specifications. If either opening or
closing voltages are not to specifications, replace the solenoid.
PIPER AIRCRAFT
PA-28RT-201 / 201T
MAINTENANCE MANUAL
THIS SPACE INTENTIONALLY LEFT BLANK
3G20
80-10-13
Page 80-09
December 1, 1978