12
Service of the Hammer and Anvil
The tools required for servicing the ham-
mer and anvil are, a 9/64
″
hex wrench, a
1/4
″
hex wrench, a 7/8
″
deep well socket
with handle, a torque wrench that reads in
inch/pounds, and threadlocker.
Remove the four (4) bolts in the bottom of
the lower driver body (p/n 301030). Use
caution as the handle tubes (p/n 300220)
have anti-vibration springs (p/n 300720)
installed and they are under tension.
When the lower driver body is removed,
it should appear as shown in
Fig. 12
. The
anvil o-ring retainer (p/n 301110) will
sometimes be removed with the lower
driver body or remain in place.
Remove the anvil o-ring cup (p/n 301090)
and the anvil (p/n 301160). This can be
easily accomplished by pushing a 1
″
dowel
rod or hammer handle into the chuck tube
from the opposite side. When the parts
are removed, note the order and disas-
semble for inspection. Check the anvil for
any wear. The anvil o-ring (p/n 301616)
should be replaced at this time. Clean
the anvil and carefully replace the anvil
o-ring.
(Fig 13)
shows an anvil with the
o-ring in place.
Remove the large retainer o-ring seals
(p/n 301614) and the large retainer (p/n
301110) from the anvil o-ring cup. Inspect
the large retainer. The large retainer o-ring
seals (p/n 301614) should be replaced
at this time. Replace the large retainer if
there are any signs of damage or excessive
wear.
The anvil o-ring retainer can be removed
from the end of the cylinder in the post
driver body (p/n 301010) by hand.
Use caution as it can become sharp with
use of the driver. Remove the hammer (p/n
301080), piston and connecting rod assem-
bly (p/n 301075) by removing the crank
pin (p/n 300050). Access to the crank pin
is achieved by removing the crankcase
cover (p/n 300130), which is described
in the section titled “Servicing Crank-
shaft and Piston Lubrication.” Remove
the crank pin using the 7/8
″
deep well
Fig. 13
-
Anvil with O-ring in place.
GPD-40 Fence Pro™ Service Instructions... continued
Fig. 12
-
View when Lower Driver Body
removed .
