Piper Aircraft Corporation Cherokee 140 PA-28-140, Service Manual

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PIPER CHEROKEE SERVICE MANUAL
01/31/08 VIIA - LANDING GEAR AND BRAKE SYSTEM
(PA-28R)
2H21
7A-16. CLEANING, INSPECTION AND REPAIR OF NOSE GEAR DOOR ASSEMBLY.
a. Clean all parts with a suitable cleaning solvent.
b. Inspect doors for cracks or damage, loose or damaged hinges and brackets.
c. Inspect door retraction rods for damage and rod end bearing for corrosion.
d. Check the door tension spring for wear and tension below minimum allowable tolerance. Reject
spring if load tension is below 8.0 pounds pull at 4.75 inches.
e. Check general condition of bellcrank and roller assembly.
f. Repairs to the doors may be replacement of hinges, repair of fiberglass and painting.
g. Repairs to the retraction mechanism is limited to replacement of parts, and sanding and painting.
7A-17. INSTALLATION OF NOSE GEAR DOOR ASSEMBLY. (Refer to Figure 7A-7.)
a. The roller assembly (5) of the retraction mechanism may be installed by first assembling the roller
(6), threaded link (7) and roller links (5), and then installing this assembly on its mounting bracket.
Ascertain that an insulator sleeve is installed with the attachment bolt and link bolt.
b. The bellcrank assembly (4) of the retraction mechanism may be installed by positioning the
bellcrank between its mounting bushing and inserting the insulator sleeve and bushing tube. Install
a cotter pin through each attachment bushing and the pivot tube. New tubes will require a 0.070
hole drilled through each end to facilitate a cotter pin. Use the existing hole in the mounting
bushings as a guide. Do not connect link between roller assembly and bellcrank until time of door
adjustment.
c. Install the gear door(s) by positioning the hinge halves of the door and cowl, and inserting the hinge
pin. It is recommended a new pin be used. Bend the end of the pin to secure in place.
d. Install the cowl and adjust doors as given in paragraph 7A-18.
7A-18. ADJUSTMENT OF NOSE GEAR DOORS.
a. Place the airplane on jacks. (Refer to Jacking, Section II.)
b. Adjust the door retraction rods so that the gear will swing through the door opening with a .12 ± .06
of an inch clearance between the gear and door at their closest point. This can best be done with the
nose gear down, tension springs disconnected and operating the nose gear manually.
c. With door clearance adjusted, adjust the link between the roller assembly and bellcrank assembly so
that the doors will pull up tightly when gear is full up. Over-tightening may result in door buckling,
however if the link is too loose, doors will gap in flight.
d. Check all rod ends for adequate thread engagement, for safety and tightness of jam nuts.
e. Remove the airplane from jacks.