Graco 3400 manual Replace o-ring. Manual

		Troubleshooting
Problem	Cause	Solution
Pump output is low	Strainer (16) is clogged	Clean strainer.
	Piston ball (206) is not seating	Service piston ball. Manual 309250.
	Piston packings are worn or damaged	Replace packings. Manual 309250.
	O-ring (227) in pump is worn or damaged	Replace o-ring. Manual 309250.
	Intake valve ball is not seating properly	Clean intake valve. Manual 309250.
	Intake valve ball is packed with material	Clean intake valve. Manual 309250.
	Engine speed is too low	Increase throttle setting. Manual 310802.
	Clutch is worn or damaged	Adjust or replace clutch. Page 9.
	Pressure setting is too low	Increase pressure. Manual 310802.
	Fluid filter (29), tip filter or tip is	Clean filter. Manual 310802 or 309639.
	clogged or dirty
	Large pressure drop in hose with	Use larger diameter hose and/or
	heavy materials	reduce overall length of hose. Use of
		more than 100 ft of 1/4 in. hose signifi-
		cantly reduces performance of sprayer.
		Use 3/8 in. hose for optimum perfor-
		mance (50 ft minimum).
Excessive paint leakage into throat	Throat packing nut is loose	Remove throat packing nut spacer.
packing nut		Tighten throat packing nut just enough
		to stop leakage.
	Throat packings are worn or damaged	Replace packings. Manual 309250.
	Displacement rod is worn or damaged	Replace rod. Manual 309250.
Fluid is spitting from gun	Air in pump or hose	Check and tighten all fluid connections.
		Prime pump. Manual 310802.
	Tip is partially clogged	Clear tip. Manual 309639.
	Fluid supply is low or empty	Refill fluid supply. Prime pump. Manual
		310802. Check fluid supply often to
		prevent running pump dry.
Pump is difficult to prime	Air in pump or hose	Check and tighten all fluid connections.
		Reduce engine speed and cycle pump
		as slowly as possible during priming.
	Intake valve is leaking	Clean intake valve. Be sure ball seat is
		not nicked or worn and that ball seats
		well. Reassemble valve.
	Pump packings are worn	Replace pump packings. Manual 309250.
	Paint is too thick	Thin the paint according to the sup-
		plier's recommendations
	Engine speed is too high	Decrease throttle setting before prim-
		ing pump. Manual 310802.
Clutch squeaks each time clutch	Clutch surfaces are not matched to each	Clutch surfaces need to wear into each
engages	other when new and may cause noise	other. Noise will dissipate after a day of
		run time.
High engine speed at no load	Misadjusted throttle setting	Reset throttle to 3300 engine rpm at no
		load
	Worn engine governor	Replace or service engine governor

310813 Rev C 7