Cherry Aerospace G84-LS, Original Instructions Manual

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HEAD CYLINDER SUB-ASSEMBLY (744-202)
Caution: Remove Pulling Heads or other attachments before attempting to disassemble.
Disassembly instructions:

Remove screw (57) and unscrew lock ring (58) with spanner wrench 530-202.

Drain the fluid over an oil pan; dispose according to environmental regulations.

Remove rear stop (59) and piston (63) by pressing them out of the rear of the subassembly.

Remove seals (60, 61, 62, 63, 65, 66, 67 & 68) carefully using a bent hook tool.
Assembly instructions:

Inspect all components to make sure all surfaces are clean and free of burrs.

Install O-ring and back-up ring (67 & 68) into groove of head cylinder (70).

Thread seal guides 744-194 & 744-195 on both sides of the piston (64).

Mount O-ring and back-up ring (65 & 66) onto the piston (64).

Carefully push/twist piston (64) into the head cylinder (70) bore, pressing it all the way in.

Assemble O-ring, backup ring (60 & 61) and O-ring, Back-up ring (62&63) onto rear stop (59) and carefully
press it into the head cylinder.

Thread-in lock ring (58) using spanner wrench 530-202 and secure it with screw (57);
use Loctite® 242 on threads. Remove seal guides.
Swivel Assembly Instructions:

Apply Loctite 545 on the male threads of swivel (75).

Thread swivel (75) into head cylinder (70) and thread until hand tight.

Using a 7/16 wrench, tighten threads by rotating one full turn from initial thread seating
to secure in place –
Do not over tighten .

Allow Loctite to cure for 24 hours for full strength.
HANDLE SUB-ASSEMBLY (744-189)
Disassembly Instructions: Make sure that the air supply is disconnected before proceeding.

Unscrew cap screws (19) and remove manifold (35);

Drain the fluid completely into a pan and dispose according to environmental regulations.

Remove gasket (22) and O-rings (21)

Remove retaining ring (1) and the base cover (2) from the bottom of the unit.

Remove retaining ring (3) and carefully pry handle base (4) from the bottom of the unit, using a screwdriver.

Engage wrench 700A61 into the hex socket of the piston rod cap (26).

Remove locknut (6) with a ½ inch (13 mm) socket, while holding with the wrench; unscrew air piston (7) by using
wrench 530-201 and a 1 inch (26 mm) socket.

Pull the air piston (7) out through the bottom of the unit with the help of the tool P1178.

Remove power piston subassembly (84) through the top of the handle (18) using the guide tool 744-104.

Remove the packing plug (11) with the help of wrench 530-201 and a 1 ¼ inch (32 mm) Socket.

Note: To loosen it, hold the handle upside down in a vise, if necessary.

Remove the O-rings (12 and 13) and back-up rings (14) with a thin, bent hook.

Place an 1 inch (25,4 mm) rod on top of power cylinder (17) and tap it out carefully through the bottom of the unit
with a mallet.
Assembly Instructions: Lubricate O-rings with Parker
®
silicone O-ring lube or equivalent and handle all seals with care.

Make sure the gaskets and seals are in good condition and are placed correctly.

Insert the power cylinder (17) with O-rings (15 & 16) into the handle (18) bore through the bottom of handle. To
properly seat it, place an 1 inch (26 mm) bar against its bottom surface, and carefully tap into place with a mallet.

Insert O-rings (13) and back-up rings (14) in packing plug (11).

Thread packing plug in tightly against the power cylinder (17) using wrench 530-201 and a 1 ¼ inch (32 mm)
socket.

Thread seal guide tool 744-104 into the end of the power piston (25) then push into the bore of the power cylin-
der (17) through the top of handle (18). Tap it though the packing plug (11) with a mallet; remove the seal guide.

Using wrench 530-201 insert air piston (7) with quad ring (9) and back-up rings (8) into the main bore of the han-
dle (18) until it engages the threaded end of the power piston (25); tighten them together wrench 700A61.

Thread and tighten locknut (6) onto power piston (25) with a ½” socket (13 mm) at 50 to 59 in-lbs (5,65
to 6,67 N-m).

Insert handle base (4) with lubricated O-ring (5) into the bottom of the handle (18) and tap it into its seat.

Place retaining ring (3), base cover (2), and retaining ring (1).

Push the piston downwards with the help of wrench 700A61.

Fill the handle subassembly with fluid to about 1/8 inch (3 mm) above the top of the power piston (17).

Place new gasket & O-rings (21,22) on top of handle (18); mount the manifold (35) tightening screws (19) evenly.
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