10
Contact Giant Industries for service school information. Phone: (419) 531-460011) After installation of high
pressure seals (23), place seal
adaptor (20) with weep seals
& pressure ring installed,
weep return ring (25) and high
pressure weep return ring (24)
over plungers. Slide valve
casing over plungers and seat
firmly. Replace the 8 socket
head cap screws (34) and
tighten to 30 ft.-lbs.(47 NM)
in a crossing pattern
(as shown below).
8
76
5
42
13
9) Check surfaces of plunger
(16). Damaged surfaces
cause accelerated seal wear.
Deposits of all kinds must be
removed from the plungers.
IMPORTANT! Plunger
surfaces are not to be
damaged. If there are lime
deposits in the pump, care
must be taken that the drip-
return bore in parts (25)
and (26) ensure trouble-free
drip-return.
10) If the plunger pipe (16B), or
oil seal (19) is worn, remove
tension screw (16D) and re-
move along with plunger
pipe (16B). Check and clean
plunger surface (16A), check
oil scraper (16H). Remove
the gear seal adapter (20A)
and, if necessary, replace oil
seals with seal lips facing
crankcase (1).Cover thread
of tension screw (16D) with
a thin film of Loctite and
tighten carefully to 22 ft.-lbs.
(30NM).
IMPORTANT! Care must be
taken that glue does not get
between the plunger pipe (16B)
and centring sleeve (16C). The
plunger pipe should not be
strained by eccentric tightening
of the tension screw or through
damage to front surface of
plunger, otherwise it is liable to
fracture.
Torque Specifications P420/P420-0011/P420-0021/P422/P423 and P425
Position Item# Description U.S Metric
15A 07311 Screw with Washer 97 in.-lbs. 11 NM
16D 08399 Tensioning Screw 22 ft.-lbs. 30 NM
32 08373 Plug (P420, P422, P423, P425) 107 ft.-lbs. 145 NM
34 08396/08484 Cap Screw 30 ft.-lbs. 40 NM