Engine Oil Chip Detector; Removal Of Chip Detector; Inspection Of Chip Detector; Installation Of Chip Detector - Piper Cheyenne IIIA Airplane Maintenance Manual

PIPER AIRCRAFT
PA-42-720 (Advanced Trainer)
MAINTENANCE MANUAL
U. Engine Oil Chip Detector
The magnetic chip detector, located in the same place as the drain plug on the reduction gearbox, is
connected electrically to the annunciator panel lights. Illumination of chip detect light on annunciator
indicates metal contamination in oil system. If chip detect light illuminates, remove chip detector and
inspect magnetic pole pieces for contaminate. Refer to Pratt & Whitney PT6A-61 Maintenance
Manual, P/N 3034342, Chapter 79.
NOTE: When chip detector is removed for inspection, also inspect oil filter.
1. Removal of Chip Detector
(a) Remove wiring from chip detector.
(b) Remove chip detector from gearbox and discard preformed packing.
2. Inspection of Chip Detector
(a) If a single chain of magnetic particles bridges gap across detector poles and particles consists
of small slivers, clean chip detector by wiping with lint-free cloth and reinstall.
(b) If more than 10 pieces of small, nugget shaped magnetic materials exist on detector, send
engine to overhaul facility for inspection.
(c) If small amount of fuzz (powered material) exists, clean detector and reinstall. Recheck for
continuity after 10 hours of operation.
(d) If same amount of fuzz is found again, clean detector, reinstall, and make another continuity
check after another 10 hours of operation.
(e) If fuzz is found a third time with similar or greater quantities, ship engine to overhaul facility for
inspection.
3. Installation of Chip Detector
(a) Install chip detector with new preformed packing in boss on reduction gearbox.
(b) Tighten and torque the detector to 45 - 55 inch-pounds.
(c) Connect plug and safety.
V. Draining Engine Oil
1. Remove engine cowling and place suitable container or drip pan under engine.
2. Remove chip detector at 6 o'clock position on front case of reduction gearbox.
3. Remove drain plug at 6 o'clock position on accessory drive gearbox.
4. Remove drain plug from oil tank drain line.
NOTE: When operating engine on oil which differs from that previously used, or if oil system is
contaminated by other metallic matter, proceed with steps 5 through 18. If using same oil
and no contamination exists, proceed only with steps 7, 8, 17, and 18.
EFFECTIVITY:
040-999
Jan
10/90
Jan 10/90
12-10-00