Figure 6 - External Flush
Figure 7 - Internal Flush
9
SHURflo Operating Instructions, Performance,
Specifications and Parts Manual
Viton Models GMSV2A, GMSV4A, GMSV6C, GMSV2A3T, GMSV2A33T,
GMSV4A5T, GMSV4A53T, GMSV6C7T and GMSV6C73T
Teflon
®
Models GMST2A, GMST4A, GMST6C, GMST2A3T, GMST2A33T,
GMST4A5T, GMST4A53T, GMST6C7T and GMST6C73T
Form L-4089 (2/17)
NOTE: See performance chart for Max.
Torque.
4. Recheck motor and pump rotation.
Pump rotation is by-directional
(See Figure 1).
PRESSURE RELIEF VALVE
5. Standard models do not include a
pressure relief valve. If discharge
is going to be shut off, an exter-
nal pressure relief valve should be
installed.
GEAR PUMP GASKET ADJUSTMENT
FOR TEMPERATURE (See Appendix 1)
6. For operation in fluid temperatures
above 120° F, stainless steel pump
models must have the gasket thick-
ness adjusted. Use Appendix 1 to
identify pump, temperature and
gasket recommendations for adjust-
ing the cover clearance prior to
operation in elevated temperatures
or viscosities above 500 SSU.
Failure to adjust pump
cover clearances for
operating tempera-
tures above 120° F. will result in severe
pump and/or motor damage.
NOTE: When pumping fluids of high
viscosity (>500 ssu), the required torque
and HP can be reduced by adding a
gasket for increased gear clearance.
MECHANICAL SEAL FLUSH
INSTALLATION OPTIONS
7. These stainless steel pumps are
equipped with mechanical seals and
have been designed with flush ports
because mechanical seals require
cooling lubrication for long life.
a. For fluids with viscosities less than
2000 SSU, a flush is not necessary,
but the seal cavity must be pre-
filled with either the operating
fluid or a neutral fluid. This is to
ensure seal cooling and lubrication
during start-up (See Figure 5).
Failure to provide
initial seal prime can
result in the mechani-
cal seal overheating with resulting repair
costs.
b. For high viscosity fluids, a flush
will be necessary. The seal must
be cooled and lubricated by a
fluid. In the case of high viscosity
fluids, due to the precision clear-
ances between the gear teeth and
the stainless steel body, highly
viscous fluids will not be able to
adequately relieve the air in the
Flow Meter
Flow Meter
Needle Valve
Needle Valve
Check Valve
Discharge
Discharge
Suction
Suction
Seal Cavity
Seal Cavity
