Piper Arrow IV, Maintenance Manual

Page: 376 / 752

ADJUSTMENT OF MAIN LANDING GEAR.
1. Place the airplane on jacks. (Refer to Jacking, Chapter 7.)
2. Level the airplane laterally and longitudinally. (Refer to Leveling, Chapter 8.)
3. Disconnect the gear door actuating rods at either the door or the housing, as desired, by removing the
rod attachment bolt. Secure the door out of the way.
4. Adjust the gear oleo housing to obtain a vertical position with the airplane level (90 degrees to
horizontal). To do this, set 90 degrees on a bubble protractor, place the protractor along the side of the gear
piston tube and adjust the end bearing of the lower side brace link allowing the bubble of the protractor to
center when the end bearing is connected to the gear housing. This should allow an angle of 83 degrees
between the gear housing and the spar cap of the wing. Place a bushing on each side of the end bearing and
secure with bolt, washer and nut.
5. Check that the rod end has sufficient thread engagement in the end bearing, align the flat sides of the
bearing casting with the flat side of the bearing and tighten the jam nut.
6. Adjust the turnbuckle of the downlock mechanism by first ascertaining that the gear is down and
locked, and then move the retraction fitting outboard until it contacts the stop slot of the side brace link. Hold
the fitting in this position and turn the turnbuckle barrel until the downlock hooks make contact with the
lockpin. Safety the turnbuckle.
7. For easier adjustment of the downlock limit switch, it may be set at this time as given in Adjustment of
the Main Gear Down Limit Switch.
8. Retract and extend the gear manually several times to ascertain that the side brace link falls through
center, the downlock hook falls into position and there is no binding of the gear assembly.
9. The gear should be adjusted in the up position to allow the gear fork to press lightly into the rubber
bumper pad on the wing. The adjustment may be accomplished as follows:
—NOTE—
If it requires less than .025 of an inch to move the gear into the
correct adjustment, Steps B and F through H need only be
followed.
A. Ascertain that the rod end bearing of the actuating cylinder is disconnected from the retraction
fitting.
B. Actuate the hydraulic system to bring the hydraulic cylinder to the up position by turning the
master switch on, raising the emergency gear extension lever and moving the gear selector handle
to the up position. Retain the emergency extension lever in the up override position. The piston of
the cylinder should be bottomed.
C. Raise the gear by pushing up on the retraction fitting, thus disengaging the hooks, and pushing up
on the point at the bottom of the side brace links to bring the links out of the locked position. Raise
the gear until the fork presses lightly into the rubber pad. Retain the gear in this position.
D. Loosen the jam nut on the piston rod of the actuating cylinder and turn the rod end bearing in or
out to allow a slip fit of the attachment bolt.
E. Install with the attachment bolt, bushing, spring swivel and secure with washer and nut. Install the
gear downlock spring.
F. When the gear is to within .125 of an inch of correct adjustment, the rod end need not be
disconnected and therefore all that will be required is to loosen the jam nut, place a wrench on the
flat at the end of the piston rod and turn to obtain correct adjustment.
G. Check the rod end bearing for adequate thread engagement and tighten jam nut.
H. If the downlock limit switch is properly adjusted, retract and extend the gear hydro-electrically to
ascertain that the gear operates properly.
32-10-07
Page 32-18
December 1, 1978
2E1
PIPER AIRCRAFT
PA-28RT-201 / 201T
MAINTENANCE MANUAL