GHC SERIES
OM-05845
PAGE E-13
MAINTENANCE AND REPAIR
Install the jam nut (D) on the adjustment capscrew
(10AM), and thread the capscrew into the bonnet
until the desired height (“A”, Figure E‐6) is reached.
Refer to the separate Parts List accompanying
your pump, and determine the specific hydraulic
size (D, G or J). See Table E-2 and adjust the
capscrew (10AM) to the proper “A” dimension for
desired cracking pressure.
Never operate the pump without the ad
justing screw jam nut in place. Other
wise, the relief valve spring(s) can be
compressed too far for the valve to
open. If the valve does not open, exces
sive pressure can develop, causing
damage to the pump and possible injury
to personnel.
50 MIN.
1.17 FULLY OUT
100
.93
125
.83
150
.72
175
.61
200
.50
240 MAX.
.31 FULLY IN
30 MIN.
1.17 FULLY OUT
50
.88
75
.57
95 MAX.
.31 FULLY IN
CRACKING
PRESSURE
(PSI)
PUMP
HYDRAULIC
SIZE
SINGLE
SPRING
OPTION CODE
DOUBLE
SPRING
OPTION CODE
DIMENSION
“A” (INCHES)
Fig. E‐7)
CRACKING
PRESSURE
(PSI)
DIMENSION
“A” (INCHES)
Fig. E‐7)
STD
JG, JJ,
JL, JP,
NF
NK, NM,
NP
NOT
REQ'D
Table E‐2. Cracking (Valve Opening) Settings ( Denotes Factory Setting)
After adjustment, tighten the jam nut (D) flush
against the bonnet.
Place the optional warning tag (10AR) between the
bonnet and the cap (10AN). Install the cap, and
tighten until fully seated against the bonnet.
Relief Valve (10) Installation
Lubricate and install the O‐ring(s) (10C) on the
housing assembly (04A) or the head assembly
(01A). Secure the relief valve (10A) with the caps
crews (B).
Do not return the pump to service with
out the warning plate (10AB) installed.
Failure to observe the warning on the
plate could result in destruction of the
pump, and injury or death to personnel.
If the warning plate (10AB) has been removed, se
cure it with the drive screws (BM).
