BOOM HOIST CYLINDERS
Then turn the thread ring until the two countersunk holes
2. Oil or grease the inside of the cylinder bore and piston
thoroughly. Then carefully position the piston in the
are aligned with the holes in the head gland. Install the two
mouth of the cylinder, and rock the rod slightly to com-
countersunk head screws. and tighten both screws evenly
until both screws are tight.
press the piston ring, as they enter the cylinder bore. Slide
the head gland into the cylinder bore.
4. Install screw (1) with a washer and tighten it snugly to
lock the thread ring.
5. After the cylinder is reinstalled on the machine, cycle
If the head gland has difficulty sliding into the cylin-
the cylinder slowly a full stroke in both directions repeatly
der bore, a pair of bar clamps should be used to apply
to purge the trapped air from the cylinder.
a steady pressure to the head gland, which will cause
the seals to compress and enter the bore.
3. Note the location of the two tapped holes in the head
gland and mark these locations on the outside of the cylind-
When air is present in the cylinders, jerky and/or
er. Screw the thread ring into the cylinder bore until it is
irratic operation of the cylinders can be expected.
flush with the end of the cylinder.
Figure 5B-2 Boom Hoist Cylinder (38U92)