Graco Mark VII

1. Pump throat packings are worn. Tighten packing nut/wet cup. If leakage continues, replace packings; see pump manual. Also check piston valve seat for hardened paint or nicks and replace if necessary. Tighten packing nut/wet-cup.
2. Intake valve ball is packed with material Clean intake valve; see pump manual.
3. Pressure setting is too low Turn Pressure Control Knob clockwise to increase pressure.
4. Material is too thick for asmall diameter Hose,orHose is too long. Use larger diameter Hose and/or reduce overall length of Hose.
5. Amp switch is on low setting. (10A or 15A setting) Switch to 16A or 20A setting.

From 3A6342 rev G, page 37

1. Tip is partially clogged Refer to Clear Spray Tip Clog , page 25.
2. Material supply low, orairwas not properly purged during priming. Refill fluid supply. Refer to FillPump(Prime Pump) , page 21. Then Fill Spray Gun and Hose , page 21. Check fluid supply often to prevent running pump dry.

From 3A6342 rev G, page 37

1. Intake valve is stuck to seat. Removefootvalve.Cleanandinspectintake valve.
2. Suction tube o-ring on foot valve is damaged or missing. Replace Suction Tube o-ring.
3. Air in pump Refer to FillPump (PrimePump) , page 21. Then Fill Spray Gun and Hose , page 21.
4. Intake valve is leaking Clean intake valve. Be sure ball seat is not nicked or worn and that ball seats well. Reassemble valve.
5. Pump packings are worn Replace pump packings; see pump manual.

From 3A6342 rev G, page 37

1. Pressure Control Knob is set too low Increase pressure by turning Pressure Control Knob clockwise.
2. Spray tip clogged Refer to Clear Spray Tip Clog , page 25.

From 3A6342 rev G, page 37

1. Displacement pump pin damaged or missing; see pump manual. Replace pump pin if missing. Be sure retainer spring is fully in groove all around connecting rod; see pump manual.
2. Connecting rod assembly damaged; see pump manual. Replace connecting rod assembly; see pump manual.
3. Gears or drive housing damaged. Inspect drive housing assembly and gears for damage and replace if necessary; see pump manual.

From 3A6342 rev G, page 37

1. Multiple electrical issues. See flow chart, page 46.

From 3A6342 rev G, page 39

1. Multiple electrical issues. See flow chart, page 48.

From 3A6342 rev G, page 39

1. Transducer or transducer connection issue. 1. Make sure there is no pressure in the system (see Pressure Relief Procedure , page 18). Check fluid path for clogs, such as clogged filter. 2. Use airless paint spray Hose with no metal braid 1/4 in. x 50 ft minimum. Smaller Hose or metal braid Hose may result in high-pressure spikes. 3. Set sprayer to OFF and disconnect power to sprayer. 4. Check transducer and connections to control board. 5. Disconnect transducer from control board socket. Check that transducer and control board contacts are clean and secure. 6. Reconnect transducer to control board socket. Connect power, set sprayer ON and control knob 1/2 turn clock - wise. If sprayer does not run properly, set sprayer to OFF and go to next step. 7. Install new transducer. Connect power, set sprayer ON and control knob 1/2

From 3A6342 rev G, page 39

1. Transducer connection issue (control board is not detecting a pressure signal). 1. Set sprayer to OFF and disconnect power to sprayer. 2. Check transducer and connections to control board. 3. Disconnect transducer from control board socket. Check to see if trans - ducer and control board contacts are clean and secure. 4. Reconnect transducer to control board socket. Connect power, set sprayer ON and control knob to 1/2 turn clock - wise. If sprayer does not run, set sprayer to OFF and go to next step. 5. Connect a confirmed working trans - ducer to control board socket. 6. Set sprayer ONandcontrol knob to 1/2 turn clockwise. If sprayer runs, install new transducer. Replace control board if sprayer does not run. 7. Check transducer resistance with ohm - meter (less than 9k ohm between red and black wires and 3-6kohm between green and yellow wires).

From 3A6342 rev G, page 39

1. Control board detected voltage surges. Set sprayer to OFF and disconnect power to sprayer. Locate a good voltage supply to prevent damage to electronics.

From 3A6342 rev G, page 40

1. Control is commanding motor to run but motor shaft does not rotate. 1. Remove pump and try to run sprayer. If motor runs, check for locked or frozen pump or drive train. If sprayer does not run, continue to step 2. 2. Set sprayer to OFF and disconnect power to sprayer. 3. Remove motor cover. 4. Disconnect motor connector(s) above motor. Check that connectors are clean. Reconnect connectors. Check that connectors are fully seated and secure. 5. Set sprayer to OFF and spin motor fan 1/2 turn. Restart sprayer. If sprayer runs, replace control board. If sprayer does not run, continue to step 5. 6. Perform Spin Test: Test at large 4-pin motor field connector. Disconnect fluid pump from sprayer. Test motor by plac - ing a jumper across pins 1 & 2. Rotate motor fan at about 2 revolutions per sec - ond. Acogging resistance to motion should be felt at the fan. The motor should be replaced if no resistance is felt. Repeat for pin combinations 1 & 3 and 2 & 3. Pin 4 (the green wire) is not used in this test. If all spin test is posi - tive, continue to step 6. See connections on next page:

From 3A6342 rev G, page 40

1. Motor overheated NOTE: Motor must be cooled down for the test. 1. Keep sprayer in cooler location with good ventilation. Make sure motor air intake is not blocked. 2. Remove motor cover. Ensure fan is securely attached to motor shaft. 3. Check thermal switch connector (yel - low wires) above motor. 4. Disconnect thermal switch connector above motor. Make sure contacts are clean and secure. Measure resistance of the thermal switch. If reading is not correct, replace motor. Check Motor Thermal Switch: Unplug thermal wires. Set meter to ohms. Meter should read the proper resistance for each unit (see table below). - ti13140a

From 3A6342 rev G, page 43

1. Incoming voltage too low for sprayer operation 1. Set sprayer to OFF and disconnect power to sprayer. 2. Remove other equipment that uses the same circuit. 3. Locate a good voltage supply to avoid damage to electronics.

From 3A6342 rev G, page 44

1. Control board is over heating. 1. Make sure motor air intake is not blocked. 2. Make sure fan is securely attached to motor shaft. 3. Replace control board. 4. Replace motor.

From 3A6342 rev G, page 44

1. Excessive current protection enabled Cycle power on and off.

From 3A6342 rev G, page 44

1. Motor not spinning (no current to motor) 1. Set sprayer to OFF and disconnect power to sprayer. 2. Remove motor cover. 3. Disconnect motor control and inspect for damage at connectors. 4. Reconnect motor control. 5. Turn power on. If code continues, replace control board.

From 3A6342 rev G, page 44

1. Spray tip worn. Replace tip. See separate gun or tip manual.
2. Spray tip clogged. Clear tip. See Clear Spray Tip Clog , page 26.
3. Paint supply. Refill and reprime pump.
4. Intake strainer clogged. Remove and clean, then reinstall. If problem persists, strain the paint.
5. Intake valve ball and piston ball are not seating properly. Remove intake valve and clean. Check balls and seats for nicks; replace if necessary. See pump manual. Strain paint before using to remove particles that could clog pump.
6. Fluid filter or tip filter is clogged or dirty. Remove and clean, then reinstall.
7. Prime valve leaking. Repair prime valve.
8. Verify pump does not continue to stroke when gun trigger is released. (Prime valve not leaking.) Service pump. See pump manual.
9. Leaking around throat packing nut which may indicate worn or damaged packings. Tighten packing nut/wet-cup. Replace packings. See pump manual. Also check piston valve seat for hardened paint or nicks and replace if necessary.

From 3B0070 rev C, page 37

1. Low stall pressure. Pressure setting is too low. Change spray mode to High Pressure. Turn pressure knob fully clockwise. Make sure pressure control knob is properly installed to allow full clockwise position. Perform Knob Calibration , page 32. If problem persists, replace pressure transducer.
2. Pump rod damage. Repair pump. See pump manual.
3. Piston packings are worn or damaged. Replace packings. See pump manual.
4. O-ring in pump is worn or damaged. Replace o-ring. See pump manual.
5. Intake valve ball is packed with material. Clean intake valve. See pump manual.
6. Large pressure drop in hose with heavy materials. Reduce overall length of hose. Use larger diameter hose.
7. Check extension cord for correct size. See Extension Cords , page 16.
8. Connecting rod assembly damaged. Replace connecting rod assembly.
9. Amp switch is on low setting. Switch to a 16A or 20A setting.

From 3B0070 rev C, page 38

1. Error code on the display. Determine fault correction from electrical, see page 39.
2. Motor cables damaged or loose connections. Reconnect or replace if necessary.
3. Potentiometer wire damaged or loose connections. Reconnect or replace if necessary.
4. Control board, see page 40. Replace power cord or control board.
5. Additional motor troubleshooting. See page 41.

From 3B0070 rev C, page 38

1. Connecting rod assembly damaged. Replace connecting rod assembly.

From 3B0070 rev C, page 38

1. Throat packing nut is loose. Remove throat packing nut spacer. Tighten throat packing nut just enough to stop leakage.
2. Throat packings are worn or damaged. Replace packings.
3. Displacement rod is worn or damaged. Replace rod.

From 3B0070 rev C, page 38

1. Air in pump or hose. Cycle pump as slowly as possible during priming. Purge paint through gun by following Startup , page 22.
2. Spray tip is partially clogged. Clear tip. See Clear Spray Tip Clog , page 26.
3. Fluid supply is low or empty. Refill fluid supply. Prime pump. Check fluid supply often to prevent running pump dry.

From 3B0070 rev C, page 38

1. Clog in prime valve. Remove prime valve, check for clogs, replace.
2. Air in pump or hose. Check and tighten all fluid connections. Cycle pump as slowly as possible during priming.
3. Intake valve is leaking. Clean intake valve. Be sure ball seat is not nicked or worn and that ball seats well. Reassemble valve.
4. Pump packings are worn. Replace pump packings. See pump manual.
5. Paint is too thick. Thin the paint according to supplier recommendations.

From 3B0070 rev C, page 38

1. Leak in suction tube. Replace suction tube.
2. Debris stuck in inlet ball. Remove foot valve and clean with appropriate cleaning solution.

From 3B0070 rev C, page 38

Unplug sprayer and turn the ON/OFF switch to OFF . Wait 30 seconds, then plug power supply cord into a properly grounded electrical outlet. Switch back ON again (this ensures sprayer is in normal run mode). Turn pressure control knob clockwise 1/2 turn. Error code will be shown on display.

From 3B0070 rev C, page 39

Motor should spin freely with no binding or excessive cogging. If motor binds or requires excessive force to spin, replace motor. With multimeter, measure the resistance between the following phases: A to B B to C A to C Resistance values should be equal. If resistance values are significantly different from one another (>0.5 Ω), replace motor. Install pump. Install control board. Install top sprayer shroud.

From 3B0070 rev C, page 41

1. Control board is not receiving a motor position sensor signal Turn power OFF. Disconnect motor position sensor and inspect for damage at connectors. Reconnect sensor. Turn power ON. If code continues, replace motor

From 3A2244 rev A, page 13

1. Control board is overheating Make sure motor air intake is not blocked. Make sure fan has not failed. Make sure control board is properly connected to back plate and that conductive thermal paste is used on power components. Replace control board or motor

From 3A2244 rev A, page 13

1. Multiple electrical issues See flow chart

From 3A6342 rev G, page 39

1. Multiple electrical issues See flow chart

From 3A6342 rev G, page 39