Graco 309550U Manual De Usuario

Follow Pressure Relief Procedure, page 15, 

before checking or repairing gun.

Check all possible problems and causes before 

disassembling gun.

To prevent cross-contamination of the gun’s wetted 
parts, do not interchange A component (isocyanate) 
and B component (resin) parts.

Gun does not fully actuate when trig-
gered.

Safety lock engaged.

Disengage safety lock, page 10.

Plugged muffler (22).

Clean, page 20.

Damaged air valve o-rings (24).

Replace, page 33.

Fluid does not spray when gun is fully 
actuated.

Closed fluid valves (12b).

Open.

Plugged impingement ports.

Clean, page 21.

Plugged check valves (26).

Clean, page 31.

Gun actuates slowly.

Plugged muffler (22).

Clean, page 20.

Damaged piston o-rings (16, 17).

Replace, page 32.

Dirty air valve, or damaged o-rings 
(24).

Clean air valve or replace o-rings, 
page 33.

Gun delays, then actuates abruptly.

Cured material around side seals 
(18).

Inspect side seals (18c) and mix 
chamber (19) for scratches. Replace, 
page 29.

Retaining ring (9) not bottomed out.

Tighten retaining ring until bottomed 
out.

Loss of round pattern.

Dirty mix chamber nozzle.

Clean, page 21.

Loss of flat pattern.

Plugged spray tip.

Clean in compatible solvent, page 18.

Worn tip.

Replace, page 18.

Dirty mix chamber nozzle.

Clean, page 21.

Leakage between flat tip and mix 
chamber.

Tip not seated properly.

Reassemble, page 18.

Damaged/missing o-ring (40).

Replace, page 18.

Pressure imbalance.

Plugged impingement ports.

Clean, page 21.

Plugged check valves (26).

Clean, page 31.

Viscosities not equal.

Adjust temperature to compensate.