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“Jaw” Style Coupling NEMA C-face Installation
1. Measure the distance from the face of the input adapter
to the face of the coupling as shown and record that
measurement.
2. Subtract the “X” dimension from the measured distance.
This needs to be done so that the coupling will not be
preloaded after installation!
3. Use that measurement to locate the coupling from the
face of the motor onto the shaft.
4. The metal portion of the coupling should be heated up
prior to assembly, generally 250ºF to 300ºF (120ºC to
150ºC).
Notice: DO NOT HEAT URETHANE SPIDER
5. Once in place, tighten the setscrew to lock coupling in
place. Let the coupling cool down before placing the
spider into the jaws. It is recommended that the key is
staked or bonded (Loctite) in place to prohibit the key
from vibrating out.
6. Mount the motor onto the input adapter with customer
supplied bolts. Make sure that the coupling from the
adapter and the motor engage securely. Use lock
washers or Loctite to prohibit bolts from becoming loose
from vibration.
Jaw Style NEMA Motor Coupling Installation
Coupling
Size
“X”
(Subtract this value from measured distance)
R14
0.06” (1.5 mm)
R19 & 24
0.08” (2.0 mm)
R28
0.10” (2.5 mm)
R38 & 42
0.12” (3.0 mm)
R48
0.14” (3.5 mm)
R65
0.18” (4.5 mm)
R90
0.22” (5.5 mm)
PUMP ROTATION
A right-hand pump rotates clockwise with the intake and relief
valve on the right side, when viewed from the driven end.
A left-hand pump rotates counterclockwise with the intake
and relief valve on the left side, when viewed from the driven
end.
NOTICE:
On GNX(H) models, the gear reducer input shaft will
rotate in the opposite direction of the pump shaft. For
example, on a right-hand GNX(H) pump, the gear reducer
shaft will rotate counterclockwise. The motor fan can be
used to ensure proper rotation.
NOTICE:
Confirm correct pump rotation by checking the pump
rotation arrows respective to pump driver rotation.
TO CHANGE PUMP ROTATION
To reverse rotation, the pump must be disassembled then
reassembled with the shaft on the opposite side of the pump.
See the ‘Maintenance’ section for instructions.
CHECK VALVES
The use of check valves or foot valves in the supply tank is
not recommended with self-priming, positive displacement
pumps.
If the possibility of liquid backflow exists when the pump is
off, a check valve in the pump discharge piping is
recommended because the pump can motor in the reverse
rotation and create undue stress on all attached components.
Never start a pump when it is rotating in the reverse rotation
as the added starting torque can damage the pump and
related equipment.
