E. Corrosion Prevention
SUBTASK 53-11-37-610-041
(1) Make the regular inspection of INSPECTION AND DETECTION, SUBJECT 51-00-51 to stop or
find the start of corrosion. Missing fasteners, white powdery or any discolored deposits are
signs of corrosion.
SUBTASK 53-11-37-610-042
(2) If you find corrosion (web bulges, missing fasteners or large amounts of discolored deposits at
fastener heads or faying surfaces), refer to Structural Repair Manual for details of corrosion
removal.
SUBTASK 53-11-37-610-043
(3) For small amounts of corrosion, to decrease the downtime of the airplane, clean off the
corrosion products. Apply a corrosion inhibiting compound into the affected area to stop the
corrosion process Ref (STANDARD PREVENTIVE MAINTENANCE PROCEDURES,
SUBJECT 51-00-59). Repair the finish system at the next maintenance opportunity.
SUBTASK 53-11-37-610-044
(4) Prevention Treatment
(a) At first opportunity consistent with scheduled maintenance activity, corrosion prevention
treatment should be accomplished in the door opening area.
(b) Treatment of the door at the same time as the door opening is recommended.
(c) Remove traffic debris and generally clean the entire door opening area. Remove reveal
and scuff plate where applicable.
(d) Remove sidewall lining and insulation blankets to expose frames, stringers, doublers and
skin.
(e) Remove door reveal, scuff plates and thresholds.
(f) Remove floor panels to gain access to floor beams and intercostals near the door
opening.
(g) Open plugged drains.
(h) Make sure that all drain paths are clear at the equipment access doorway, fwd and aft
galley and entry doorways and cargo doorway.
(i) Replace damaged or broken finishes. Refer to STANDARD PREVENTIVE
MAINTENANCE PROCEDURES, SUBJECT 51-00-59 for protective finish system.
(j) Apply a coat of epoxy primer, C00259 to the inboard flange surfaces of stringers and
allow to dry thoroughly.
(k) Apply sealant, A00247, class F, chromate-loaded sealant to the inboard flanges and to
portions of the frames that come in contact with insulation blankets. Allow to cure for 48
hours. Note condition of the sealant and reapply as necessary.
(l) Apply corrosion inhibiting compound to all immediate structure. Special efforts should be
made to apply the corrosion inhibitor along doubler edges, along faying surfaces and on
fastener heads. The use of spray equipment with nozzle directed into faying surfaces in
recommended. Special attention should be given to flanges of floor beams, doorsills and
floor beam to fuselage frame splices.
(m) Replace or repair broken or damaged leveling compounds used for drainage.
(n) Allow solvent in corrosion inhibiting compound to evaporate before reinstalling insulation
blankets.
737-600/700/800/900
AIRCRAFT MAINTENANCE MANUAL
53-11-37
Page 235
D633A101-ILF Oct 15/2018
ECCN 9E991 BOEING PROPRIETARY - Copyright © Unpublished Work - See title page for details
EFFECTIVITY
ILF ALL
To Next Page
Loading...
