Service Manual User guide

HYDRAULIC CYLINDERS

NOTE: Replace all seals whenever a cylinder is dissassembled for repair.

DISSASSEMBLY

Remove cylinder from machine.

Use a spanner wrench and mallet to unscrew the rod bearing from the

cylinder barrel. Do not use a pipe wrench to remove the bearing.

The aluminum rod bearing may not unscrew if the cylinder is warm.

Carefully pull the rod assembly straight out of the barrel. Use air

to work the piston to the end of its stroke if necessary.

Remove the piston retaining lock nut and slide piston off rod.

Slide the rod bearing off the rod.

Carefully inspect all parts for scoring or deep scratches. Replace

as required.

REASSEMBLY

Clean all parts thoroughly.

Lubricate the rod seal and wiper with hydraulic oil and install in rod

bearing. Replace bearing on rod.

Replace “O” ring in inner groove of piston and remount piston on rod.

Examine nylon insert lock nut carefully to determine if reuse is ad-

visable. Lubricate threads with hydraulic oil and torque nut to

specification:

1" Nut 150-175 lb ft

1-1/2" “ 600-650 “ “

1-3/4" “ 950-1000 “ “

2-1/2" “ 1800-2000 “ “

Lubricate piston seal grooves with hydraulic oil.

Warm the teflon piston seals to approximately 110 - 120 F. (still

comfortable to handle by hand) in warm water. Do not apply flame heat

to seal

Work the piston seal into groove as quickly as possible, using installa-

tion tool or small pocket screwdriver with smooth edges to work the seal

in one groove at a time.

Allow seal to cool 10-20 minutes to return to original diameter before

assembling piston into barrel.

Position cylinder barrel vertically for reassembly of cylinder. Lubricate

piston seals with hydraulic oil. Protect piston seals from being damaged

by cylinder barrel threads with .0010 - .0015 shim stock during assembly.

Lubricate with hydraulic oil and install new back-up ring and “O” ring

in outer groove of rod bearing. Screw rod bearing into cylinder barrel

and use spanner wrench and mallet to tighten until rod bearing flange is

firmly sealed.