Cleaning Valves - Graco USP Instructions Manual

Blockages
Blockages result in a higher than normal pumping pres-
sure. Depending on the application or system design,
this blockage will usually result in a complete loss of
lubricant flow into the total system and no bearing will be
receiving lubrication.
The loss of flow due to a blockage is first indicated with
the higher than normal system pressure that is devel-
oped by the pump as it attempts to overcome this block-
age. Higher pressure is limited, isolated and signaled
through the use of various performance indicators (reset
and relief) and incorporated into the system design.
Contact your Graco distributor for available parts.
Contamination Blockage
If dirt, foreign material or any other form of contamina-
tion is found in a valve, cleaning that valve will only tem-
porarily solve contamination blockage problems. The
source of the contamination must be eliminated for sat-
isfactory service.
The system filtering method must be investigated. Filter
elements should be inspected and cleaned if necessary.
The reservoir filling method should be reviewed to elimi-
nate any chance of foreign material entering the reser-
voir during filling.
Separation Blockage
If a hard wax or soap-like material is found in the Valve
Section, grease separation is occurring. This means that
the oil is being squeezed from the grease at normal sys-
tem operating pressure and the grease thickener is
being deposited in the divider valve. Cleaning the divider
valve will only temporarily solve the problem. Consult
your lubricant supplier for recommendations on alter-
nate lubricants and your local Graco distributor to verify
compatibility with centralized lubricating systems.
3A3116B

Cleaning Valves

• Dirt and foreign material will damage lubricating
equipment. Perform all service and disassembly
under the cleanest possible conditions.
• Hard or sharp metal objects such as punches,
screwdrivers, and picks can scratch and dam-
age piston bore. When cleaning these surfaces
use a brass rod and hand pressure only.
1. Remove end plugs only and try to move each piston
back and forth without removing the piston from the
valve section.
If all pistons move freely and there is no indication
of a more serious problem:
2. Replace end plugs.
Blockages
NOTICE
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