Inspection Frequency; Adjust Needle Assembly; Service Valve Stem And Seal - Graco 311209J Instructions And Parts List

Service

Inspection Frequency

Dispense Valve
Inspect dispense valve at every use for leakage or other
visible damage.
Heater
Every two weeks, check heater for proper resistance.
Resistance should be approximately 890 ohms, +/- 70
ohms for the 240V valves. Replace heater if necessary.
Also inspect heater when performing regular mainte-
nance procedures.
Sensor
Every two weeks, check sensor resistance. Resistance
should be 108 ohms at 70° F (21° C). Replace sensor if
necessary.
Also inspect sensor when performing regular mainte-
nance procedures.

Adjust Needle Assembly

The trigger travel and corresponding valve opening are
factory set. To adjust this setting, use the following pro-
cedure.
1. Relieve pressure in system.
2. Disconnect gun from hose.
3. Use 11/32 in. wrench to loosen hex nut (4g).
12
4. Trigger gun and use a 1/8 in. open-end wrench on
flats of needle to turn needle (4a) clockwise one turn
as viewed from handle end of gun.
5. Release trigger; a slight free play of the trigger han-
dle should occur.
6. Repeat Step 4 until free play occurs.
7. Tighten hex nut (4g) to lock the adjustment.

Service Valve Stem and Seal

If fluid leaks past seal (4c), the seal or needle (4a) may
be worn or damaged. To replace seal or valve stem, use
the following procedure.
1. Relieve pressure in system.
2. Disconnect gun from hose.
3. Remove cover (16), and then slide heater cartridge
and sensor cartridge out of body (2).
4. Loosen needle nut.
5. Remove screws (33).
6. Unscrew needle with body from yoke.
7. Remove seal-cartridge assembly from body and
replace seals and/or needle. Repack grease area of
packing nut prior to reassembly.
8. Reassemble in reverse order and follow Adjust
Needle Assembly, page 12.
311209J