AN 01-25CN-2

PARAGRAPH 4

(b) Place,the piston in the wooden block clamp, screw on the piston bearing as far as it will go, and lineup the bearing lock pin hole with the hole in the piston. Screw the lock pin into the piston until it is tight.    (c) Release the piston from the wooden block clamp. Install the cylinder in a wooden block clamp and secure the clamp in a vise with the cylinder in a horizontal position.    (d) Install the metering pin in the cylinder and tighten with the metering pin wrench (Drawing No. 87-88-031). Be sure that a new copper gasket is installed with the metering pin. Never install a used gasket.    (e) Guide the piston bearing and piston into the cylinder, wet the packings and washers thoroughly with hydraulic oil (Spec. 3586), and slide the first washer over the piston and into the cylinder. Install the packings one at a time as on the original installation. The correct order of washer and packing installation is shown on figure 65. When the last washer and packing ring is installed, slide the gland nut over the piston and tighten it into the cylinder. Never tighten this gland nut excessively.    (f) Insert the hooked end of the retainer ring into one of the two holes that line up with a slot in the gland nut. Expand the retainer and slide it onto the cylinder until it engages in the groove on the cylinder. The hooked end on this retainer should extend far enough through the cylinder to engage the gland nut and lock it in position.    (g) With the Schrader plug removed, extend the piston as far as it will go. Stand the cylinder in a vertical position with the piston up and fill the piston at the plug hole with hydraulic oil (Spec. 3586) until it overflows. Screw a pressure gage into the plug hole in the piston and subject the strut to a pressure of 2500 p.s.i. for ten minutes.    (h) Inspect the cylinder to determine if -there is any evidence of leaks around the gland nut.    (i) If there is no evidence of leaks in the strut, release the pressure on the strut and remove the gage. Drain the oil from the strut and retract the strut into the cylinder as far as it will go.

Stand the strut on end with the plug hole up and fill with hydraulic oil (Spec. 3586) until the oil overflows, and work the piston up and down several times to dispel any trapped air in the cylinder. Add additional fluid to bring the level up to the plug hole. Install the gasket and Schrader plug and inflate the strut with a high pressure hand pump to 3471/2 p.s.i. Never use compressed air. The oleo strut is now completely assembled, tested and serviced with fluid and air for installation in the airplane. (6) TO INSTALL THE OLEO STRUT IN THE AIRPLANE-To install the oleo strut in the airplane, reverse the procedure outlined in (3), (a) through (d). (7) TO REMOVE THE TAIL WHEEL RETRACTING STRUT FROM THE FUSELAGE.    (a) Unbutton the access door and the two round inspection holes at the aft end of the fuselage on the left side. Unbutton the inspection door near the top of the fuselage on the right side. The retract. ing strut is located on the center line of the airplane at the top of the fuselage between Stations 13 and L5 with a piston guide extending to Station 12. The retracting strut is bolted to attachment fittings on Stations 13 and 14 bulkheads.    (b) Place a jack under the rear jack point aft of the tail wheel doors to support the airplane.    (c) If the oleo strut is installed, disconnect it at the lug on the retracting strut piston.    (d) Disconnect the hydraulic line from the for. ward and aft ends of the cylinder.    (e) Disconnect the position transmitter linkage at the eye bolt on the piston lug.    (f) Remove the two attaching bolts at Station 13 bulkhead.    (g) Remove the two attaching bolts at Station 14 bulkhead and pull the retracting cylinder aft until the piston guide is free of the support at Station 12 bulkhead.    (h) Remove the retracting cylinder from the fuselage through the access door below the horizontal stabilizer.

---