Gun Operation Troubleshooting | Graco Inc 247937, 247936, 312900C

Gun Operation Troubleshooting

Electric Shock Hazard

Installing and servicing this equipment requires access to parts which may cause an electric shock or other serious injury if the work is not performed prop- erly. Do not install or repair this equipment unless you are trained and qualified.

Pressurized Equipment Hazard

To reduce the risk of an injury, follow the Pressure Relief procedure on page 19 whenever you are instructed to relieve the pressure.

NOTE: Check all possible remedies in the Troubleshoot- ing Chart before disassembling the gun

Problem	Cause	Solution

Excessive spray fog.	Atomizing air pressure too high.	Close restrictor valve some, or
		decrease air pressure as low as pos-
		sible; minimum 40 psi (0.28 MPa, 2.8
		bar) needed at gun for full voltage.

	Fluid too thin.	Increase viscosity.

“Orange Peel” finish.	Atomizing air pressure too low.	Open atomizing air valve more or
		increase gun air inlet pressure; use
		lowest air pressure necessary.

	Poorly mixed or filtered fluid.	Remix or refilter fluid.

	Fluid too thick.	Reduce viscosity.

Fluid leaks from the fluid packing	Worn packings or rod.	Replace packings or rod; see page
area		30.

Air leaks from the front of the gun	Air valve (21) is not seating properly.	Clean and service air valve; see
		page 34.

Fluid leakage from the front of the	Worn or damaged packing rod (26).	Replace; see page 30
gun

	Worn fluid seat.	Replace fluid nozzle and/or needle;
		see page 28.

	Loose fluid nozzle (7).	Tighten; see page 28.

	Damaged nozzle o-ring (7b).	Replace; see page 28.

Gun does not spray	Low fluid supply.	Add fluid if necessary.

	Damaged air cap (9).	Replace; see page 28.

	Dirty or clogged fluid nozzle (7).	Clean; see page 28.

	Damaged fluid nozzle (7).	Replace; see page 28.

	Damaged fluid adjustment valve (25).	Replace; see page 34.

Dirty air cap	Misaligned air cap (9) and fluid	Clean fluid buildup off air cap and
	nozzle (7).	fluid nozzle seat; see page 28.

312900C