Graco Viscount II, Instructions-Parts List Manual

Page: 11 / 30

Operation
3A0537G 11
Operation
Pressure Relief Procedure
1. Shut off the hydraulic supply line valve (S) first, then
the return line valve (R).
2. Open the dispensing valve, if used.
3. Open all fluid drain valves (U) in the system, having
a waste container ready to catch drainage. Leave
drain valve(s) open until you are ready to pump
again.
Prime the Pump
1. Fill the TSL reservoir to the Maximum fill line with
Throat Seal Liquid (TSL). See F
IG
. 4 on page 13.
NOTE: During operation the TSL level in the reservoir
will fluctuate slightly at pump changeover.
2. Close the flow control valve (T) by turning knob
counterclockwise reducing pressure to zero. Close
the supply line shutoff valve (S) and the return line
shutoff valve (R). Also verify that all drain valves (U)
are closed.
3. Check that all fittings throughout system are tight-
ened securely.
4. Start the hydraulic power supply.
5. Open the return line shutoff valve (R), then the sup-
ply line shutoff valve (S). Slowly turn the flow control
valve (T) clockwise, increasing pressure until pump
starts.
6. Cycle pump slowly until all air is pushed out and
pump and hoses are fully primed.
7. Verify that pump actuations are priming the pump
wet-cup. If not, confirm that the TSL pump piston is
being depressed at bottom changeover, and that
reservoir check valves are not stuck closed.
8. Close the fluid shutoff valve (D) downstream of the
pump. The pump should stall against pressure.
NOTE: In a circulation system, the pump operates con-
tinuously until the power supply is shut off. In a
direct-supply system, the pump starts when the dis-
pense valve is opened, and stops when the dispense
valve is closed.
Stop the Pump at the Bottom of
Its Stroke
Relieve the pressure when you stop the pump for any
reason. Stop the pump on the downstroke, before the
motor changes over.
Shutdown
Follow Pressure Relief Procedure , page 11.
Always flush the pump before the fluid dries on the dis-
placement rod. See
Flushing on page 12.
NOTICE
When shutting down the hydraulic system, always
shut off the hydraulic supply line shutoff valve (S) first,
and then the return line shutoff valve (R) to prevent
overpressurizing the motor or its seals. When starting
the hydraulic system, open the return line shutoff
valve first.
NOTICE
Failure to stop the pump at the bottom of its stroke
allows fluid to dry on the piston rod, which can dam-
age the throat packings and the TSL pump piston seal
when the pump is restarted.