MAULE AEROSPACE TECHNOLOGY, INC.
MAINTENANCE MANUAL
FOR
MX-7-420
9
Rev. A
(CAUTION: If a wing has been removed and reinstalled, or a new wing installed, visual-
ly inspect the routing of aileron cables through the inspection hole cover located on un-
derside of wing, aft of rear spar and outboard of wing strut attach brackets. Ascertain
that cables are not routed over the strut attach brackets and are properly routed
through the fairleads and around pulleys. Ref. Maule Service Bulletin No. 12.)
11. CAUTION: At inspection hole in tail, visually check the pivoting action at the control
cable attachment points over the full range of rudder and elevator travel. This ac-
tion should be such that there are no bending loads imparted to the turnbuckles
(which are designed for straight tension load only). Any binding, which causes
bending of the turnbuckles, should be removed. Any cable attachment parts, which
display appreciable corrosion, must be replaced before further flight. NOTE: Pivot
points must be cleaned and lubricated with any lightweight lubricating oil. Following
lubrication, the cable attachments, including the turnbuckles, must be heavily
coated with a good preservative such as :
Black Bear Paralketone Preventative
LPS 3, Heavy Duty Rust Inhibitor
Black Bear Co. (preferred)
LPS Laboratories, Inc.
Long Island City, NY
Tucker, GA
NOTE: Maule Service Bulletin No. 9 covers corrosive resistant parts replacement and is
particularly recommended for airplanes operating in a potentially corrosive environment.
Compliance to this SB provides for larger stainless steel turnbuckles and corrosion re-
sistant steel fasteners and attachment details for the elevator cables.
12. CAUTION: Special attention should be given to the horizontal stabilizer strut lower
attach tubes which are welded to the lower longerons. The seal on the inside of the
lower strut attach stub tubes can deteriorate with age which could cause corrosion
on the interior of the attach stub tubes, especially on floatplane models. It is rec-
ommended that the stabilizer struts be removed to inspect attach stub tubes at
each annual. If there is visible external corrosion around the attach stub tubes, or
the internal seal appears loose or cracked, remove the seal, clean the inside of the
tube and visually inspect the inside for corrosion. If corrosion is found, repair in ac-
cordance with AC 43.13-1B. After repair, or if no corrosion is found, fill entire tube
with silicone rubber to seal tube from moisture. Inspect the struts for dents, corro-
sion, or punctures and replace if necessary. Reinstall struts with new hardware and
document in aircraft records.
13. Lubricate all chains and points of rotation on sprockets, pulleys and bellcranks.
14. Inspect and lubricate all control surface hinges and control horn connections.
15. Lubricate door hinges and latches and seat tracks.
CAUTION: Carefully inspect all door hinge bolts and nuts for condition and security. If
using elastic nuts on door hinges, they must be replaced with castle nuts and cotter
pins. Refer to Maule Service Letter No. 61.
