Graco Inc 308639L important safety instructions Troubleshooting, Problem Cause Solution

Troubleshooting

WARNING

To reduce the risk of serious injury, including splashing fluid in the eyes or on the skin, follow the Pressure Relief Procedure on page 9. You must do this whenever this manual instructs you to relieve pressure, when you shut off the pump, and before checking, adjusting, cleaning, moving, or repairing any system equipment.

NOTE: Check all possible problems and causes before you disassemble the pump.

PROBLEM

CAUSE

SOLUTION

Pump cycles at stall or fails to hold pres-	Worn check valve balls (201), seats	Replace. See page 14.
sure at stall.	(101) or o-rings (102).
Pump will not cycle, or cycles once and	Air valve is stuck or dirty.	Disassemble and clean air valve. See
stops.		pages 12 to 13. Use filtered air.
	Check valve ball (201) severely worn	Replace ball and seat. See page 14.
	and wedged in seat (101) or manifold
	(50 or 53).
	Check valve ball (201) is wedged into	Install a pressure relief valve
	seat (101), due to overpressurization.	(see page 7).
	Dispensing valve is clogged.	Relieve pressure and clear valve.
Pump operates erratically.	Suction line is clogged.	Inspect; clear.
	Sticky or leaking check valve balls	Clean or replace. See page 14.
	(201).
	Diaphragm (301) is ruptured.	Replace. See pages 15 to 17.
	Restricted exhaust.	Remove restriction.
Air bubbles in fluid.	Suction line is loose.	Tighten.
	Diaphragm (301) is ruptured.	Replace. See pages 15 to 17.
	Loose inlet manifold (53), damaged seal	Tighten manifold bolts (54), or replace
	between manifold and seat (101), or	seats (101) or o-rings (102). See
	damaged o-rings (101).	page 14.
	Loose diaphragm shaft bolt (14).	Tighten or replace. See pages 15 to 17.
	Damaged o-ring (102).	Replace. See pages 15 to 17.
Fluid in exhaust air.	Diaphragm (301) is ruptured.	Replace. See pages 15 to 17.
	Loose diaphragm shaft bolt (14).	Tighten or replace. See pages 15 to 17.
	Damaged o-ring (102).	Replace. See pages 15 to 17.
Pump leaks air externally.	Air valve cover screws (3) are loose.	Tighten screws. See page 13.
	Air valve gasket (20) or air cover gasket	Inspect; replace. See pages 12 to 13,
	(10) is damaged.	18 to 19.
Pump leaks fluid externally from ball	Loose manifolds (50 or 53), damaged	Tighten manifold bolts (54), or replace
check valves.	o-ring (102) between manifold and seat.	o-rings (102). See page 14.

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