Slip Ring Assemblies Alignment; Slip Ring Assemblies Replacement - Piper PA-44-180 SEMINOLE Maintenance Manual

3. Restack modules and spacer as shown in Figure 30-9.
Ascertain flat washer is positioned between star washer and housing.
4. Reconnect aircraft wire harness and insure adjacent ring terminals are not touching.
5. Install assembly on aircraft and check adjustment.
ALIGNMENT OF NEW BRUSHES.
Any time the brush block assembly is dismounted, the alignment at reinstallation must be checked as described
in Step 7 under "100 Hour Inspection".
SLIP RINGS.
ALIGNMENT OF SLIP RING ASSEMBLIES.
Excessive slip ring run-out will result in severe arcing between the slip ring and brushes and will cause rapid
brush wear. If the run-out is not corrected. rapid deterioration of the slip ring and brush contact surfaces will
result and lead to eventual failure of the Deicing System. Check the slip ring run-out with a dial indicator
securely attached to the engine with the pointer resting on the slip ring. (Refer to Figure 30-4) Rotate the
propeller slowly noting the run-out indicated on the gauge. The total run-out must not exceed 0.005 inch ±
0.0025 inch and 0.002 inch in any 4 inch interval of slip ring travel.
Some error may be induced in the readings by pushing in or pulling out on the
propeller. Care must be taken to exert a uniform push or pull.
Small amounts of run-out may be corrected by varying the torque on the slip ring mounting bolts between to
100 inch-pounds to obtain the required flatness.
REPLACEMENT OF SLIP RING ASSEMBLIES.
Slip ring assemblies that are open or shorted electrically, cracked or damaged structurally, or which have
damaged surfaces beyond the scope of minor repair or clean up. should be replaced.
PIPER AIRCRAFT
PA - 4 4 - 1 8 0 / 1 8 0 T
AIRPLANE MAINTENANCE MANUAL
— Note —
— Note —
2E17
3 0 - 6 7 - 0 2
Page 30-37
Revised: May 15, 1989