Smiths Aerospace
Electronic Systems – Malvern
DOC NO.0134ED
MAINTENANCE MANUAL SUPPLEMENT
BOEING B737-100/200/300/400/500
28-41-04
TRANSIENT SUPPRESSION UNIT – REMOVAL/INSTALLATION
1. General
A. TSUs are location specific. Refer to IPL for location.
B. Use extreme care when performing maintenance as damage to the receptacle and/or TSU requires
replacement of wire bundle and/or TSU.
2. Equipment and Materials
A. Lock, Leading Edge Flap Drive Unit. (Ref 27-81-00)
B. Lock, Ground. (Ref 32-00-30)
C. Solvent – Isopropyl Alcohol BMS 11-7 or equivalent.
D. Lubricant – MIL-H-5606. (Ref 20-30-03)
E. Clean, Lint-free rags
3. Prepare for Removal
WARNING: TO AVOID INJURY TO MAINTENANCE PERSONNEL OR DAMAGE TO EQUIPMENT,
MAKE CERTAIN THAT ADEQUATE PRECAUTIONS ARE TAKEN WHILE PERFORMING
ANY WORK IF ELECTRICAL POWER IS APPLIED TO THE AIRCRAFT.
A. Open and tag the following circuit breakers (P6 panel):
(1) FUEL QUANTITY
(2) EP GROUND REFUELING
(3) FUEL PANEL INDICATOR
ENSURE AIRCRAFT IS ELECTRICALLY GROUNDED.
USE EXTREME CARE WHEN PERFORMING MAINTENANCE, AS DAMAGE TO THE
RECEPTACLE REQUIRES REPLACEMENT OF THE WIRE BUNDLE ASSEMBLY.
WARNING: REFER TO 27-81-00 MP FOR LOCK INSTALLATION PROCEDURES. FLAPS WILL
RETRACT IN 7 SECONDS. INSTALL LOCKS TO PREVENT INJURY FROM
INADVERTENT OPERATION OF FLAPS.
B. If replacing wing fuel tank TSU extend the leading edge flaps and install leading edge flaps drive unit
safety locks in accordance with MM 27-81-00 MP.
WARNING: REFER TO 32-00-01 MP FOR GROUND LOCK INSTALLATION PROCEDURES. AN
ACCIDENTAL RETRACTION OF THE LANDING GEAR MAY INJURE PERSONNEL
OR DAMAGE EQUIPMENT.
4.
Page 414
Apr 19/02
Airplanes with Smiths 2307 Model Fuel Quantity
Indicators with TSU
EFFECTIVITY