NPK GH1 - Alternate Piston and Sleeves Installation Method

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REASSEMBLY OF THE HAMMER
ALTERNATE METHOD OF INSTALLING THE PISTON AND
SLEEVES INTO THE MAIN BODY
This is the preferred method as it keeps the piston and sleeves together as one unit.
This prevents sleeve separation, which could allow dowels to drop out of place. Also,
the steady push of the portable power unit reduces the possibility of cutting o-rings or
back up rings.
1. Pin chain (t4) to diagonally opposite
tie rod holes (44) in main body (A)
at tool end (1).
String chain (t4) through tie rod holes
and wrap around back of portable
power RAM cylinder (t5).
Support the end of the “B” sleeve (P)
with a sling (t27) and insert into the gas
end of the main body (A). Bump with a
dead blow hammer (t2). Align ports
with main body (A).
Push “B” sleeve into body from gas end
of body (1) with portable power unit
(t33).
Push “B” sleeve (P) using a push plate
(t26) almost flush with gas end of body
(1). Watch o-rings and back up rings
as they enter bore. If seal starts to
extrude, stop and push seal back into
groove.