Graco GMAX II 5900

Manuals, pump repair kits, parts and troubleshooting for the Graco GMAX II 5900, from Graco's own manuals and parts lists.

Find your version

Find the model number on your sprayer's data plate and match it to the first column. Each row shows the pump Graco's Parts Book lists for that model and the pump's repair kit.

Repair kits listed

Graco GMAX II 5900 versions
Model numberParts Book titleSeriesYearsPump and repair kit
17E829GMAX II 5900 Standard Lo-Boy1/2019-/
  • Pump 16X419 $919.80 ProContractor ProConnect II Pump Kit (Standard)Repair kit 248213 $108.58
17E830GMAX II 5900 Standard Convertible1/2019-/
  • Pump 16Y706 Standard Threaded Pump (Standard)Repair kit 248213 $108.58
17E831GMAX II 5900 Standard Hi-Boy1/2019-/
  • Pump 16Y706 Standard Threaded Pump (Standard)Repair kit 248213 $108.58
17E832GMAX II 5900 ProContractor Hi-Boy1/2019-/
  • Pump 17H824 $1,528.80 ProConnect II MaxLife Vortex Pump (Standard)Repair kit 17K162 $148.88
17E833GMAX II 5900 IronMan Hi-Boy1/2019-/
  • Pump 17H826 $1,831.20 ProConnect II MaxLife Extreme (Standard)Repair kit 17K162 $148.88
17E839GMax II 5900 HD 3-in-11/2019-/
  • Pump 17H829 Standard Pump Kit (Standard)Repair kit 17H846 $142.56
17H808GMAX II 5900 Standard Lo-Boy1/2019-/
  • Pump 16X419 $919.80 ProContractor ProConnect II Pump Kit (Standard)Repair kit 248213 $108.58
17H810GMAX II 5900 Standard Hi-Boy1/2019-/
  • Pump 16Y706 Standard Threaded Pump (Standard)Repair kit 248213 $108.58
17H819TexSpray 5900 HD Standard1/2019-/
  • Pump 17H829 Standard Pump Kit (Standard)Repair kit 17H846 $142.56
2245243012 With GMax 5900 PumpB2/1991-6/2006
  • Pump 240291 Displacement PumpRepair kit 248213 $108.58
2326205900 GMAX Hi Boy(Bare)(Non Display)5/1998-1/2002
  • Pump 240291 Displacement PumpRepair kit 248213 $108.58
2326215900 GMax Hi Boy (Non Display)8/1998-1/2000
  • Pump 240291 Displacement PumpRepair kit 248213 $108.58
Show all 54 models
Graco GMAX II 5900 versions, continued
Model numberParts Book titleSeriesYearsPump and repair kit
2326225900 GMax Lo Boy(Bare)(Non Display)5/1998-1/2002
  • Pump 240291 Displacement PumpRepair kit 248213 $108.58
2326235900 GMax Lo Boy (Non Display)?/?-1/2000
  • Pump 240291 Displacement PumpRepair kit 248213 $108.58
2326245900, GMax, Convertible, No Display4/1998-1/2002
  • Pump 240291 Displacement PumpRepair kit 248213 $108.58
2326255900 GMAX CONV Non Display8/1998-1/2000
  • Pump 240291 Displacement PumpRepair kit 248213 $108.58
2326265900 GMAX CONV Non Display8/1998-8/1999
  • Pump 240291 Displacement PumpRepair kit 248213 $108.58
2326275900 GMAX H.D. (Non Display)5/1998-12/2001
  • Pump 240800 Displacement PumpRepair kit 248213 $108.58
2326295900 GMAX CONV Non Display8/1998-8/1999
  • Pump 240291 Displacement PumpRepair kit 248213 $108.58
2326805900 GMAX CONV Non Display8/1998-8/1999
  • Pump 240291 Displacement PumpRepair kit 248213 $108.58
2326825900 GMAX CONV Non Display8/1998-8/1999
  • Pump 240291 Displacement PumpRepair kit 248213 $108.58
2337055900 GMax Bare/LoBoy6/2001-4/2005
  • Pump 244224 Displacement PumpRepair kit 248213 $108.58
2337065900 GMax Bare/HiBoy6/2001-4/2005
  • Pump 244224 Displacement PumpRepair kit 248213 $108.58
2337075900 GMax Complete/LoBoy8/2001-3/2005
  • Pump 244224 Displacement PumpRepair kit 248213 $108.58
2337085900 GMax Complete/HiBoy8/2001-4/2005
  • Pump 244224 Displacement PumpRepair kit 248213 $108.58
2337095900 GMax Conv/Hi7/2001-4/2005
  • Pump 244224 Displacement PumpRepair kit 248213 $108.58
2337105900 GMax Conv/Hi8/2001-4/2005
  • Pump 244224 Displacement PumpRepair kit 248213 $108.58
2337115900 GMax Conv/Hi8/2001-4/2005
  • Pump 244224 Displacement PumpRepair kit 248213 $108.58
2337125900 GMax Conv/Hi8/2001-4/2005
  • Pump 244224 Displacement PumpRepair kit 248213 $108.58
2337135900 GMax Conv/Lo8/2001-4/2005
  • Pump 244224 Displacement PumpRepair kit 248213 $108.58
2337145900 GMax Conv/Lo8/2001-4/2005
  • Pump 244224 Displacement PumpRepair kit 248213 $108.58
2337155900 GMax Conv/Lo8/2001-4/2005
  • Pump 244224 Displacement PumpRepair kit 248213 $108.58
2337165900 GMax HD Hi bare6/2001-4/2005
  • Pump 244201 Displacement PumpRepair kit 248213 $108.58
2337175900 GMax HD HI COMP8/2001-4/2005
  • Pump 244201 Displacement PumpRepair kit 248213 $108.58
2486875900, GMax II, Standard, Lo-BoyB1/2010-3/2014
  • Pump 287513 Pump KitRepair kit 248213 $108.58
2486875900, GMax II, Standard, Lo-BoyA6/2004-1/2010
  • Pump 287513 Pump KitRepair kit 248213 $108.58
2486885900, GMax II, Standard, Hi-BoyB1/2010
  • Pump 287513 Pump KitRepair kit 248213 $108.58
2486885900, GMax II, Standard, Hi-BoyA6/2004-1/2010
  • Pump 287513 Pump KitRepair kit 248213 $108.58
2486895900, GMax II, Premium, Lo-Boy6/2004-1/2010
  • Pump 287513 Pump KitRepair kit 248213 $108.58
2486915900, GMax II, Standard, Convertible, Hi-BoyB1/2010-2/2015
  • Pump 287513 Pump KitRepair kit 248213 $108.58
2486915900, GMax II, Standard, Convertible, Hi-BoyA6/2004-1/2010
  • Pump 287513 Pump KitRepair kit 248213 $108.58
2486925900, GMax II, Convertible, Premium, Hi-Boy6/2004-1/2010
  • Pump 287513 Pump KitRepair kit 248213 $108.58
2486935900, GMax II, Convertible, Standard, Hi-BoyB1/2010-3/2014
  • Pump 287513 Pump KitRepair kit 248213 $108.58
2486935900, GMax II, Convertible, Standard, Hi-BoyA6/2004-1/2010
  • Pump 287513 Pump KitRepair kit 248213 $108.58
2486945900, GMax II, Convertible, Standard, Lo-BoyB1/2010
  • Pump 287513 Pump KitRepair kit 248213 $108.58
2486945900, GMax II, Convertible, Standard, Lo-BoyA6/2004-1/2010
  • Pump 287513 Pump KitRepair kit 248213 $108.58
2486955900, GMax II, Convertible, Lo-BoyB1/2010
  • Pump 287513 Pump KitRepair kit 248213 $108.58
2486955900, GMax II, Convertible, Lo-BoyA6/2004-1/2010
  • Pump 287513 Pump KitRepair kit 248213 $108.58
2486965900, GMax II, Convertible, Premium, Lo-Boy6/2004-1/2010
  • Pump 287513 Pump KitRepair kit 248213 $108.58
2486975900, GMax II, Convertible, Standard, Lo-BoyB1/2010
  • Pump 287513 Pump KitRepair kit 248213 $108.58
2486975900, GMax II, Convertible, Standard, Lo-BoyA6/2004-1/2010
  • Pump 287513 Pump KitRepair kit 248213 $108.58
2488895900, GMax II, Convertible, Hi-Boy7/2004-1/2010
  • Pump 287513 Pump KitRepair kit 248213 $108.58
2488905900, GMax II, Convertible, Premium, Lo-Boy7/2004-1/2010
  • Pump 287513 Pump KitRepair kit 248213 $108.58
2587375900, GMax II, Premium, Lo-Boy1/2010-3/2014
  • Pump 287513 Pump KitRepair kit 248213 $108.58

Manuals

Links open the manufacturer's official copy.

Parts we sell for the Graco GMAX II 5900

Filters (11)
Gun (4)
  • 241705 HEAVY DUTY GUN,SPRAY,TEXTURE
  • 287032 KIT, FILTER,GUN,60 MESH
  • 287033 KIT, FILTER,GUN,100 MESH
  • 288488 KIT, REPAIR, GUN, CONTRACTOR
Hose (8)
Kit (8)
  • 17D888 KIT, REPLACEMENT, POTENTIOMETER
  • 17H846 KIT, REPAIR, PKG, MV STD, QP
  • 17Y297 KIT, REPAIR, CARTRIDGE, PC GUN
  • 17Y466 KIT, TRIGGER, CONTRACTOR PC
  • 244240 KIT, REPAIR, RETURN LINE, HI
  • 248215 KIT, REPAIR, INTAKE TUBE
  • 287952 KIT,REPAIR,DRAIN HOSE
  • 288732 KIT, REPAIR, DRAIN HOSE
Motor (4)
Packing (6)
Pump (4)
  • 16X419 KIT,PUMP,5900 PCII
  • 17H824 KIT, PUMP, 5900PCII, MAXLIFE
  • 17H826 KIT, PUMP, 5900PCII, IRONMAN
  • 248213 KIT, REPAIR,PUMP,1095/1595
Tip (4)
  • 17Y042 CONTRACTOR PC GUN,RAC X,LTX,PKGD
  • 288420 CONTRACTOR GUN,RAC X(PKGD)
  • LTX517 RAC X LTX TIP,SPRAY,517
  • LTX531 RAC X LTX TIP,SPRAY,531
Valve (4)
  • 235014 KIT, REPLACEMENT, DRAIN VALVE
  • 245103 KIT REPAIR, DRAIN VALVE
  • 24B156 VALVE, PRIME, HD, THREAD PATCH
  • 257352 KIT, REPAIR, PRIME VALVE, HD
Other parts (5)

Troubleshooting from the manual

E=XX is displayed
  1. Fault condition exists Determine fault correction from table, page 14.

From 309409 rev F, page 6

Engine won't start
  1. Engine switch is OFF Turn engine switch ON
  2. Engine is out of gas Refill gas tank. Honda Engines Owner's Manual.
  3. Engine oil level is low Try to start engine. Replenish oil, if necessary. Honda Engines Owner's Manual.
  4. Spark plug cable is disconnected or damaged Connect spark plug cable or replace spark plug
  5. Cold engine Use choke
  6. Fuel shutoff lever is OFF Move lever to ON position
  7. Oil is seeping into combustion chamber Remove spark plug. Pull starter 3 to 4 times. Clean or replace spark plug. Start engine. Keep sprayer upright to avoid oil seepage.

From 309409 rev F, page 6

False tripping of WatchDog system. EMPTY is displayed. Pump does not run.
  1. Operating conditions out of WatchDog param- eters Low pump output; page 7. Turn pressure down. Contact Graco Technical Assistance to adjust WatchDog parameters. Operate without WatchDog active; Manual 309408.

From 309409 rev F, page 6

Engine operates, but dis- placement pump does not operate
  1. Error code displayed? Reference pressure control repair. Page 15.
  2. Pump switch is OFF Turn pump switch ON.
  3. Pressure setting is too low Turn pressure adjusting knob clockwise to increase pressure.
  4. Fluid filter (318) is dirty Clean filter. Page 24.
  5. Tip or tip filter is clogged Clean tip or tip filter. Manual 309091.
  6. Displacement pump piston rod is stuck due to dried paint Repair pump. Manual 309277.
  7. Connecting rod is worn or damaged Replace connecting rod. Page 8.
  8. Drive housing is worn or damaged Replace drive housing. Page 9.
  9. Electrical power is not energizing clutch field Check wiring connections. Page 13. Reference pressure control repair. Page 15. Reference wiring diagram. Page 25. With pump switch ON and pressure turned to MAXIMUM, use a test light to check for power between clutch test points on control board. Remove 7- -pin connector from control board and measure resistance across clutch coil. At 70 _ F, the resistance must be between 1.2  0.2  (GMax 3900); 1.7  0.2  (GMax 5900); if not, replace pinion housing. Have pressure control checked by authorized Graco dealer.
  10. Clutch is worn, damaged, or incorrectly positioned Replace clutch. Page 10.
  11. Pinion assembly is worn or damaged Repair or replace pinion assembly. Page 10.

From 309409 rev F, page 6

Pump output is low
  1. Strainer (31) is clogged Clean strainer. Sprayer 233716 strainer is for use in paint only.
  2. Piston ball (206) is not seating Service piston ball. Manual 309277.
  3. Piston packings are worn or damaged Replace packings. Manual 309277.
  4. O-ring (227) in pump is worn or damaged Replace o-ring. Manual 309277.
  5. Intake valve ball is not seating properly Clean intake valve. Manual 309277.
  6. Intake valve ball is packed with material Clean intake valve. Manual 309277. Do not leave 233716 sprayer under pressure for more than 5 minutes when spraying texture and not actively spraying.
  7. Engine speed is too low Increase throttle setting. Manual 309408.
  8. Clutch is worn or damaged Replace clutch. Page 10.
  9. Pressure setting is too low Increase pressure. Manual 309408.
  10. Fluid filter (318), tip filter or tip is clogged or dirty Clean filter. Manual 309408 or 309091.
  11. Large pressure drop in hose with heavy materials Use larger diameter hose and/or reduce overall length of hose. Use of more than 100 ft of 1/4 in. hose significantly reduces performance of sprayer. Use 3/8 in. hose for optimum perfor- mance (50 ft minimum).

From 309409 rev F, page 7

Excessive paint leakage into throat packing nut
  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. Manual 309277.
  3. Displacement rod is worn or damaged Replace rod. Manual 309277.

From 309409 rev F, page 7

Fluid is spitting from gun
  1. Air in pump or hose Check and tighten all fluid connections. Reprime pump. Manual 309408.
  2. Tip is partially clogged Clear tip. Manual 309091.
  3. Fluid supply is low or empty Refill fluid supply. Prime pump. Manual 309408. Check fluid supply often to prevent running pump dry.

From 309409 rev F, page 7

Pump is difficult to prime
  1. Air in pump or hose Check and tighten all fluid connections. Reduce engine speed and cycle pump as slowly as possible during priming.
  2. Intake valve is leaking Clean intake valve. Be sure ball seat is not nicked or worn and that ball seats well. Reas- semble valve.
  3. Pump packings are worn Replace pump packings. Manual 309277.
  4. Paint is too thick Thin the paint according to the supplier's recommendations
  5. Engine speed is too high Decrease throttle setting before priming pump. Manual 309408.

From 309409 rev F, page 7

Clutch squeaks each time clutch engages
  1. Clutch surfaces are not matched to each other when new and may cause noise Clutch surfaces need to wear into each other. Noise will dissipate after a day of run time.

From 309409 rev F, page 7

High engine speed at no load load
  1. Misadjusted throttle setting Reset throttle to 3700 engine rpm at no load
  2. Worn engine governor Replace or service engine governor

From 309409 rev F, page 7

Gallon counter not working
  1. Bad sensor, broken or disconnected wire. Displaced or missing magnet. Check connections. Replace sensor or wire. Reposition or replace magnet.

From 309409 rev F, page 7

No display, sprayer operates
  1. Display damaged or has bad connection Check connections. Replace display.

From 309409 rev F, page 7

E=XX is displayed
  1. Fault condition exists Determine fault correction from table, page 15

From 310893 rev P, page 6

Engine will not start
  1. Engine switch is OFF Turn engine switch ON
  2. Engine is out of gasoline Refill gas tank. Honda Engines Owner's Man- ual.
  3. Engine oil level is low Try to start engine. Replenish oil, if necessary. Honda Engines Owner's Manual.
  4. Spark plug is disconnected or damaged Connect spark plug cable or replace spark plug
  5. Cold engine Use choke
  6. Fuel shutoff lever is OFF Move lever to ON position
  7. Oil is seeping into combustion chamber Remove spark plug. Pull starter 3 to 4 times. Clean or replace spark plug. Start engine. Keep sprayer upright to avoid oil seepage

From 310893 rev P, page 6

False tripping of WatchDog system. EMPTY is displayed. Pump does not run.
  1. Operating conditions out of WatchDog parameters Pump output is low, page 7. Turn pressure down. Contact Graco Technical Assistance to adjust WatchDog parameters. Operate without WatchDog active; Manual 310892.

From 310893 rev P, page 6

Engine operates, but displacement pump does not operate
  1. Error code displayed Reference Pressure Control repair, page 15
  2. Pump switch is OFF Turn pump switch ON
  3. Pressure setting too low Turn pressure adjusting knob clockwise to increase pressure.
  4. Fluid filter (56) is dirty Clean filter. Page 28.
  5. Tip or tip filter is clogged Clean tip or tip filter. Manual 309639.
  6. Displacement pump piston rod is stuck due to dried paint Repair pump. Manual 310894.
  7. Connecting rod is worn or damaged Replace connecting rod. Page 8.
  8. Drive housing is worn or damaged Replace drive housing. Page 9.
  9. Electrical power is not energizing clutch field Check wiring connections. Page 12. Reference Digital Display Messages . Page 15. Reference wiring diagram. Page 29. With pump switch ON and pressure turned to MAXI- MUM, use a test light to check for power between clutch test points on control board. Remove clutch wires from control board and measure resistance across clutch coil. At 70° F, the resistance must be between 1.2 +0.2 Ω ; if not, replace pinion housing. Have pressure control checked by authorized Graco dealer
  10. Clutch is worn, damaged, or incorrectly Adjust or replace clutch. Page 10.
  11. Pinion assembly is worn or damaged Repair or replace pinion assembly. Page10.

From 310893 rev P, page 6

Pump output is low
  1. Strainer (82) is clogged Clean strainer.
  2. Piston ball is not seating Service piston ball. Manual 310894.
  3. Piston packings are worn or damaged Replace packings. Manual 310894.
  4. O-ring in pump is worn or damaged Replace o-ring. Manual 310894.
  5. Intake valve ball is not seating properly Clean intake valve. Manual 310894.
  6. Intake valve ball is packed with material Clean intake valve. Manual 310894.
  7. Engine speed is too low Increase throttle setting. Manual 310892.
  8. Clutch is worn or damaged Adjust or replace clutch. Page 10.
  9. Pressure setting is too low Increase pressure. Manual 310892.
  10. Fluid filter (56), tip filter or tip is clogged or dirty Clean filter. Manual 310892 or 309639.
  11. Large pressure drop in hose with heavy materials Use larger diameter hose and/or reduce overall length of hose. Use of more than 100 ft of 1/4 in. hose significantly reduces performance of sprayer. Use 3/8 in. hose for optimum performance (50 ft minimum).

From 310893 rev P, page 7

Excessive paint leakage into throat packing nut
  1. Throat packing nut is loose Remove throat packing nut spacer. Tighten throat packing nut just enough to stop leak- age.
  2. Throat packings are worn or damaged Replace packings. Manual 310894.
  3. Displacement rod is worn or damaged Replace rod. Manual 310894.

From 310893 rev P, page 7

Fluid is spitting from gun
  1. Air in pump or hose Check and tighten all fluid connections. Rep- rime pump. Manual 310892.
  2. Tip is partially clogged Clear tip. Manual 309639.
  3. Fluid supply is low or empty Refill fluid supply. Prime pump. Manual 310892. Check fluid supply often to prevent running pump dry.

From 310893 rev P, page 7

Pump is difficult to prime
  1. Air in pump or hose Check and tighten all fluid connections. Reduce engine speed and cycle pump as slowly as possible during priming.
  2. Intake valve is leaking Clean intake valve. Be sure ball seat is not nicked or worn and that ball seats well. Reassemble valve.
  3. Pump packings are worn Replace pump packings. Manual 310894.
  4. Paint is too thick Thin the paint according to the supplier's recommendations
  5. Engine speed is too high Decrease throttle setting before priming pump. Manual 310892.

From 310893 rev P, page 7

Clutch squeaks each time clutch engages
  1. Clutch surfaces are not matched to each other when new and may cause noise Clutch surfaces need to wear into each other. Noise will dissipate after a day of run time.

From 310893 rev P, page 7

High engine speed at no load
  1. Misadjusted throttle setting Reset throttle to 3300 engine rpm at no load.
  2. Worn engine governor Replace or service engine governor

From 310893 rev P, page 7

Gallon counter not working
  1. Bad sensor, broken or disconnected wire. Displaced or missing magnet. Check connections. Replace sensor or wire. Reposition or replace magnet.

From 310893 rev P, page 7

No display, sprayer operates
  1. Display damaged or has bad connection Check connections. Replace display.

From 310893 rev P, page 7

E=XX is displayed
  1. Fault condition exists Determine fault correction from table, page 14

From 311046 rev L, page 6

Engine will not start
  1. Engine switch is OFF Turn engine switch ON
  2. Engine is out of gasoline Refill gas tank. Honda Engines Owner's Man- ual.
  3. Engine oil level is low Try to start engine. Replenish oil, if neces- sary. Honda Engines Owner's Manual.
  4. Spark plug is disconnected of dam- aged Connect spark plug cable or replace spark plug
  5. Cold engine Use choke
  6. Fuel shutoff lever is OFF Move lever to ON position
  7. Oil is seeping into combustion cham- ber Remove spark plug. Pull starter 3 to 4 times. Clean or replace spark plug. Start engine. Keep sprayer upright to avoid oil seepage

From 311046 rev L, page 6

False tripping of WatchDog system. EMPTY is displayed. Pump does not run.
  1. Operating conditions out of WatchDog parameters Pump output is low, page 7. Turn pressure down. Contact Graco Technical Assistance to adjust WatchDog parameters. Operate without WatchDog active; Manual 310892.

From 311046 rev L, page 6

Engine operates, but displacement pump does not operate
  1. Error code displayed Reference Pressure Control repair, page 14
  2. Pump switch is OFF Turn pump switch ON
  3. Pressure setting too low Turn pressure adjusting knob clockwise to increase pressure.
  4. Fluid filter (29) is dirty Clean filter. Page 21.
  5. Tip or tip filter is clogged Clean tip or tip filter. Manual 309639.
  6. Displacement pump piston rod is stuck due to dried paint Repair pump. Manual 310894.
  7. Connecting rod is worn or damaged Replace connecting rod. Page 8.
  8. Drive housing is worn or damaged Replace drive housing. Page 9.
  9. Electrical power is not energizing clutch field Check wiring connections. Page 12. Reference pressure control repair. Page 14. Reference wiring diagram. Page 22. With pump switch ON and pressure turned to MAXI- MUM, use a test light to check for power between clutch test points on control board. Remove clutch wires from control board and measure resistance across clutch coil. At 70° F, the resistance must be between 1.2 +0.2 Ω ; if not, replace pinion housing. Have pressure control checked by authorized Graco dealer
  10. Clutch is worn, damaged, or incor- rectly positioned Adjust or replace clutch. Page 10.
  11. Pinion housing is worn or damaged Repair or replace pinion housing.

From 311046 rev L, page 6

Pump output is low
  1. Strainer (82) is clogged Clean strainer.
  2. Piston ball (206) is not seating Service piston ball. Manual 310894.
  3. Piston packings are worn or damaged Replace packings. Manual 310894.
  4. O-ring (227) in pump is worn or damaged Replace o-ring. Manual 310894.
  5. Intake valve ball is not seating properly Clean intake valve. Manual 310894.
  6. Intake valve ball is packed with material Clean intake valve. Manual 310894.
  7. Engine speed is too low Increase throttle setting. Manual 310892.
  8. V-belt slipping Tighten V-belt with tension bar (132). Adjust bracket until it takes 15 lb of force to lock ten- sion bar down
  9. Clutch is worn or damaged Adjust or replace clutch. Page 10.
  10. Pressure setting is too low Increase pressure. Manual 310892.
  11. Fluid filter (56), tip filter or tip is clogged or dirty Clean filter. Manual 310892 or 309639.
  12. Large pressure drop in hose with heavy materials Use larger diameter hose and/or reduce overall length of hose. Use of more than 100 ft of 1/4 in. hose significantly reduces performance of sprayer. Use 3/8 in. hose for optimum performance (50 ft minimum).

From 311046 rev L, page 7

Excessive paint leakage into throat packing nut
  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. Manual 310894.
  3. Displacement rod is worn or damaged Replace rod. Manual 310894.

From 311046 rev L, page 7

Fluid is spitting from gun
  1. Air in pump or hose Check and tighten all fluid connections. Reprime pump. Manual 310892.
  2. Tip is partially clogged Clear tip. Manual 309639.
  3. Fluid supply is low or empty Refill fluid supply. Prime pump. Manual 310892. Check fluid supply often to pre- vent running pump dry.

From 311046 rev L, page 7

Pump is difficult to prime
  1. Air in pump or hose Check and tighten all fluid connections. Reduce engine speed and cycle pump as slowly as possible during priming.
  2. Intake valve is leaking Clean intake valve. Be sure ball seat is not nicked or worn and that ball seats well. Reassemble valve.
  3. Pump packings are worn Replace pump packings. Manual 310894.
  4. Paint is too thick Thin the paint according to the supplier's recommendations
  5. Engine speed is too high Decrease throttle setting before priming pump. Manual 310892.

From 311046 rev L, page 7

Clutch squeaks each time clutch engages
  1. Clutch surfaces are not matched to each other when new and may cause noise Clutch surfaces need to wear into each other. Noise will dissipate after a day of run time.

From 311046 rev L, page 7

High engine speed at no load
  1. Misadjusted throttle setting Reset throttle to 3700 engine rpm at no load
  2. Worn engine governor Replace or service engine governor

From 311046 rev L, page 7

Gallon counter not working
  1. Bad sensor, broken or disconnected wire. Displaced or missing magnet. Check connections. Replace sensor or wire. Reposition or replace magnet.

From 311046 rev L, page 7

No display, sprayer operates
  1. Display damaged or has bad connection Check connections. Replace display.

From 311046 rev L, page 7

E=XX is displayed
  1. Fault condition exists. Determine fault correction from table, page 35.

From 3A6400 rev B, page 28

Engine will not start
  1. Engine switch is OFF. Turn engine switch ON.
  2. Engine is out of gasoline. Refill gas tank. Honda Engine Manual.
  3. Engine oil level is low. Try to start engine. Replenish oil, if necessary. Honda Engine Manual.
  4. Spark plug disconnected or damaged. Connect spark plug cable or replace spark plug.
  5. Engine is cold. Use choke.
  6. Fuel shutoff lever is OFF. Move lever to ON position.
  7. Oil is seeping into combustion chamber. Remove spark plug. Pull starter 3 to 4 times. Clean or replace spark plug. Start engine. Keep sprayer upright to avoid oil seepage.

From 3A6400 rev B, page 28

False tripping of WatchDog system. EMPTY is displayed. Pump does not run.
  1. Operating conditions out of WatchDog parameters. Pump output is low, page 29. Turn pressure down. Contact Graco Technical Assistance to adjust WatchDog parameters. Operate without WatchDog active (see Operation manual).

From 3A6400 rev B, page 28

Engine operates, but displacement pump does not operate
  1. Error code displayed. See LED Display Messages , page 38.
  2. Pump switch is OFF. Turn pump switch ON.
  3. Pressure setting too low. Turn pressure adjusting knob clockwise to increase pressure.
  4. Fluid filter is dirty. Clean filter.
  5. Tip or tip filter is clogged. Clean tip or tip filter (see gun manual).
  6. Displacement pump piston rod is stuck due to dried paint. Repair pump (see pump manual).
  7. Connecting rod is worn or damaged. See Parts manual.
  8. Drive housing is worn or damaged. See Parts manual.
  9. Electrical power is not energizing clutch field. See Parts manual. See LED Display Messages , page 38. With pump switch ON and pressure turned to MAXIMUM, use a test light to check for power between clutch test points on control board. Remove clutch wires from control board and measure resistance across clutch coil. At 70° F, the resistance must be between for 3900 - 1.2 + 0.2  , for 5900/7900 1.7 ± 0.2  ; if not, replace pinion housing. Have pressure control checked by authorized Graco dealer.
  10. Clutch is worn, damaged, or incorrectly positioned. Adjust or replace clutch. See page 39.
  11. Pinion assembly is worn or damaged. Repair or replace pinion assembly. Page 39.

From 3A6400 rev B, page 29

Pump output is low
  1. Strainer is clogged. Clean strainer.
  2. Piston ball is not seating. Service piston ball (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 not seating properly. Clean intake valve (see pump manual).
  6. Intake valve ball is packed with material. Clean intake valve (see pump manual).
  7. Engine speed is too low. Increase throttle setting (see operation manual).
  8. Clutch is worn or damaged. Adjust or replace clutch. Page 39.
  9. Pressure setting is too low. Increase pressure (see operation manual).
  10. Fluid filter, tip filter or tip is clogged or dirty. Clean filter (see gun manual).
  11. Large pressure drop in hose with heavy materials. Use larger diameter hose and/or reduce overall length of hose. Use of more than 100 ft of 1/4 in. hose significantly reduces performance of sprayer. Use 3/8 in. hose for optimum performance (50 ft minimum).

From 3A6400 rev B, page 29

Excessive paint leakage into throat packing nut
  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 (see pump manual).
  3. Displacement rod is worn or damaged. Replace rod (see pump manual).

From 3A6400 rev B, page 30

Fluid is spitting from gun
  1. Air in pump or hose. Check and tighten all fluid connections. Reprime pump (see operation manual).
  2. Tip is partially clogged. Clear tip (see gun manual).
  3. Fluid supply is low or empty. Refill fluid supply. Prime pump (see operation manual). Check fluid supply often to prevent running pump dry.

From 3A6400 rev B, page 30

Pump is difficult to prime
  1. Air in pump or hose. Check and tighten intake tube connections. Reduce engine speed and cycle pump as slowly as possible during priming.
  2. Intake valve is leaking. Clean intake valve. Be sure ball seat is not nicked or worn and that ball seats well. Reassemble valve.
  3. Pump packings are worn. Replace pump packings (see pump manual).
  4. Engine speed is too high. Decrease throttle setting before priming pump (see operation manual).

From 3A6400 rev B, page 30

Clutch squeaks each time clutch engages
  1. Clutch surfaces are not matched to each other when new and may cause noise. Clutch surfaces need to wear into each other. Noise will dissipate after a day of run time.

From 3A6400 rev B, page 30

High engine speed at no load
  1. Misadjusted throttle setting. Reset throttle to 3300 engine rpm at no load.
  2. Worn engine governor. Replace or service engine governor.

From 3A6400 rev B, page 30

Gallon counter not working
  1. Bad sensor, broken or disconnected wire. Displaced or missing magnet. Check connections. Replace sensor or wire. Reposition or replace magnet.

From 3A6400 rev B, page 30

No display, sprayer operates
  1. Display damaged or has bad connection. Check connections. Replace display.

From 3A6400 rev B, page 30

Engine operates, but displacement pump does not operate
  1. Displacement pump piston rod is stuck due to dried paint. Repair pump (see pump manual).
  2. Connecting rod is worn or damaged. See Parts manual.
  3. Drive housing is worn or damaged. See Parts manual.
  4. Electrical power is not energizing clutch field. See Parts manual. See Digital Display Messages , page 31. With pump switch ON and pressure turned to MAXIMUM, use a test light to check for power between clutch test points on control board. Remove clutch wires from control board and measure resistance across clutch coil. At 70° F, the resistance must be between for 3900 - 1.2 + 0.2 Ω , for 5900/7900 1.7 ± 0.2 Ω ; if not, replace pinion housing. Have pressure control checked by authorized Graco dealer. 32.
  5. Clutch is worn, damaged, or incorrectly positioned. Adjust or replace clutch. See page
  6. Pinion assembly is worn or damaged. Repair or replace pinion assembly. Page 32.
  7. Tip or tip filter is clogged. Clean tip or tip filter (see gun manual).
  8. Error code displayed. See Digital Display Messages , page 31.
  9. Pump switch is OFF. Turn pump switch ON.
  10. Pressure setting too low. Turn pressure adjusting knob clockwise to increase pressure.
  11. Fluid filter is dirty. Clean filter.

From 332919 rev G, page 22

E=XX is displayed
  1. Fault condition exists. Determine fault correction from table, page 31.

From 332919 rev G, page 22

Pump output is low
  1. O-ring in pump is worn or damaged. Replace o-ring (see pump manual).
  2. Strainer is clogged. Clean strainer.
  3. Piston ball is not seating. Service piston ball (see pump manual).
  4. Piston packings are worn or damaged. Replace packings (see pump manual).
  5. Intake valve ball is not seating properly. Clean intake valve (see pump manual).
  6. Intake valve ball is packed with mate- rial. Clean intake valve (see pump manual).
  7. Engine speed is too low. Increase throttle setting (see operation man- ual).
  8. Clutch is worn or damaged. Adjust or replace clutch. Page 32.
  9. Pressure setting is too low. Increase pressure (see operation manual).
  10. Fluid filter, tip filter or tip is clogged or dirty. Clean filter (see gun manual).
  11. Large pressure drop in hose with heavy materials. Use larger diameter hose and/or reduce overall length of hose. Use of more than 100 ft of 1/4 in. hose significantly reduces performance of sprayer. Use 3/8 in. hose for optimum perfor- mance (50 ft minimum).

From 332919 rev G, page 23

Clutch squeaks each time clutch engages
  1. Clutch surfaces are not matched to each other when new and may cause noise. Clutch surfaces need to wear into each other. Noise will dissipate after a day of run time.

From 332919 rev G, page 23

Engine will not start
  1. Oil is seeping into combustion cham- ber. Remove spark plug. Pull starter 3 to 4 times. Clean or replace spark plug. Start engine. Keep sprayer upright to avoid oil seepage.
  2. Engine switch is OFF. Turn engine switch ON.
  3. Engine is out of gasoline. Refill gas tank. Honda Engine Manual.
  4. Engine oil level is low. Try to start engine. Replenish oil, if necessary. Honda Engine Manual.
  5. Spark plug disconnected or damaged. Connect spark plug cable or replace spark plug.
  6. Engine is cold. Use choke.
  7. Fuel shutoff lever is OFF. Move lever to ON position.

From 332919 rev G, page 22

False tripping of WatchDog system. EMPTY is displayed. Pump does not run.
  1. Operating conditions out of WatchDog parameters. Pump output is low, page 23. Turn pressure down. Contact Graco Technical Assistance to adjust WatchDog parameters. Operate without WatchDog active (see Opera- tion manual).

From 332919 rev G, page 22

Excessive paint leakage into throat packing nut
  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 (see pump manual).
  3. Displacement rod is worn or damaged. Replace rod (see pump manual).

From 332919 rev G, page 23

Fluid is spitting from gun
  1. Air in pump or hose. Check and tighten all fluid connections. Rep- rime pump (see operation manual).
  2. Tip is partially clogged. Clear tip (see gun manual).
  3. Fluid supply is low or empty. Refill fluid supply. Prime pump (see operation manual). Check fluid supply often to prevent running pump dry.

From 332919 rev G, page 23

Pump is difficult to prime
  1. Air in pump or hose. Check and tighten all fluid connections.
  2. Intake valve is leaking. Clean intake valve. Be sure ball seat is not nicked or worn and that ball seats well. Reas- semble valve.
  3. Pump packings are worn. Replace pump packings (see pump manual).
  4. Paint is too thick. Thin the paint according to the supplier's rec- ommendations.
  5. Engine speed is too high. Decrease throttle setting before priming pump (see operation manual).

From 332919 rev G, page 23

High engine speed at no load
  1. Misadjusted throttle setting. Reset throttle to 3300 engine rpm at no load.
  2. Worn engine governor. Replace or service engine governor.

From 332919 rev G, page 23

Gallon counter not working
  1. Bad sensor, broken or disconnected wire. Displaced or missing magnet. Check connections. Replace sensor or wire. Reposition or replace magnet.

From 332919 rev G, page 23

No display, sprayer operates
  1. Display damaged or has bad connec- tion. Check connections. Replace display.

From 332919 rev G, page 23

E=XX is displayed
  1. Fault condition exists. Determine fault correction from table, page 14.

From 3A0243 rev B, page 5

Engine will not start
  1. Engine switch is OFF. Turn engine switch ON.
  2. Engine is out of gasoline. Refill gas tank. Honda Engine Manual.
  3. Engine oil level is low. Try to start engine. Replenish oil, if necessary. Honda Engine Manual.
  4. Spark plug disconnected or damaged. Connect spark plug cable or replace spark plug.
  5. Engine is cold. Use choke.
  6. Fuel shutoff lever is OFF. Move lever to ON position.
  7. Oil is seeping into combustion chamber. Remove spark plug. Pull starter 3 to 4 times. Clean or replace spark plug. Start engine. Keep sprayer upright to avoid oil seepage.

From 3A0243 rev B, page 5

False tripping of WatchDog system. EMPTY is displayed. Pump does not run.
  1. Operating conditions out of WatchDog parameters. Pump output is low, page 6. Turn pressure down. Contact Graco Technical Assistance to adjust WatchDog parameters. Operate without WatchDog active (see Opera- tion manual).

From 3A0243 rev B, page 5

Engine operates, but displacement pump does not operate
  1. Error code displayed. Reference Pressure Control repair, page 21.
  2. Pump switch is OFF. Turn pump switch ON.
  3. Pressure setting too low. Turn pressure adjusting knob clockwise to increase pressure.
  4. Fluid filter is dirty. Clean filter.
  5. Tip or tip filter is clogged. Clean tip or tip filter (see gun manual).
  6. Displacement pump piston rod is stuck due to dried paint. Repair pump (see pump manual).
  7. Connecting rod is worn or damaged. Replace connecting rod. Page 15.
  8. Drive housing is worn or damaged. Replace drive housing. Page 16.
  9. Electrical power is not energizing clutch field. Check wiring connections. Page 21. Reference Digital Display Messages . Page 14. Reference wiring diagram. Page 21. With pump switch ON and pressure turned to MAXIMUM, use a test light to check for power between clutch test points on control board. Remove clutch wires from control board and measure resistance across clutch coil. At 70° F, the resistance must be between 1.2 + 0.2 Ω ; if not, replace pinion housing. Have pressure control checked by authorized Graco dealer.
  10. Clutch is worn, damaged, or incorrectly positioned. Adjust or replace clutch. Page 19.
  11. Pinion assembly is worn or damaged. Repair or replace pinion assembly. Page 17.

From 3A0243 rev B, page 5

Pump output is low
  1. Strainer is clogged. Clean strainer.
  2. Piston ball is not seating. Service piston ball (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 not seating properly. Clean intake valve (see pump manual).
  6. Intake valve ball is packed with mate- rial. Clean intake valve (see pump manual).
  7. Engine speed is too low. Increase throttle setting (see operation man- ual).
  8. Clutch is worn or damaged. Adjust or replace clutch. Page 17.
  9. Pressure setting is too low. Increase pressure (see operation manual).
  10. Fluid filter, tip filter or tip is clogged or dirty. Clean filter (see gun manual).
  11. Large pressure drop in hose with heavy materials. Use larger diameter hose and/or reduce overall length of hose. Use of more than 100 ft of 1/4 in. hose significantly reduces performance of sprayer. Use 3/8 in. hose for optimum perfor- mance (50 ft minimum).

From 3A0243 rev B, page 6

Excessive paint leakage into throat packing nut
  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 (see pump manual).
  3. Displacement rod is worn or damaged. Replace rod (see pump manual).

From 3A0243 rev B, page 6

Fluid is spitting from gun
  1. Air in pump or hose. Check and tighten all fluid connections. Rep- rime pump (see operation manual).
  2. Tip is partially clogged. Clear tip (see gun manual).
  3. Fluid supply is low or empty. Refill fluid supply. Prime pump (see operation manual). Check fluid supply often to prevent running pump dry.

From 3A0243 rev B, page 6

Pump is difficult to prime
  1. Air in pump or hose. Check and tighten all fluid connections.
  2. Intake valve is leaking. Clean intake valve. Be sure ball seat is not nicked or worn and that ball seats well. Reas-
  3. Pump packings are worn. Replace pump packings (see pump manual).
  4. Paint is too thick. Thin the paint according to the supplier's rec- ommendations.

From 3A0243 rev B, page 6

Clutch squeaks each time clutch engages
  1. Clutch surfaces are not matched to each other when new and may cause noise. Clutch surfaces need to wear into each other. Noise will dissipate after a day of run time.

From 3A0243 rev B, page 6

High engine speed at no load
  1. Misadjusted throttle setting. Reset throttle to 3300 engine rpm at no load.
  2. Worn engine governor. Replace or service engine governor.

From 3A0243 rev B, page 6

Gallon counter not working
  1. Bad sensor, broken or disconnected wire. Displaced or missing magnet. Check connections. Replace sensor or wire. Reposition or replace magnet.

From 3A0243 rev B, page 6

No display, sprayer operates
  1. Display damaged or has bad connec- tion. Check connections. Replace display.

From 3A0243 rev B, page 6

Pump is difficult to prime
  1. Air leak Check all hose connections and tighten as needed. Reduce engine speed and cycle pump as slowly as possible during priming.
  2. Intake valve is leaking Shut off pump and relieve pressure. Disas- semble and clean intake valve. Be sure ball seat is not nicked or worn and that ball seats well. Reassemble.
  3. Worn packings Repack pump. Manual 308798.
  4. Fluid is too thick Thin fluid according to supplier's recommenda- tions.
  5. Engine speed is too high Decrease throttle setting before priming pump. Manual 308863.

From 308864 rev H

Engine won't start
  1. Spark plug cable disconnected or spark plug damaged Connect spark plug cable or replace spark plug.
  2. Oil seepage into combustion chamber Remove spark plug. Pull starter rope 3 or 4 times. Clean or replace spark plug. Try to start engine. Keep sprayer upright to avoid oil seepage.
  3. Engine oil level low Try to start engine. Replenish oil, if necessary. Honda Engines Owner's Manual.

From 308864 rev H

Engine operates, but displacement pump displacement pump doesn't
  1. Pressure control switch turned OFF Turn on.
  2. Pressure setting too low Increase pressure.
  3. Displacement pump outlet filter dirty Clean filter.
  4. Tip or tip filter clogged Clean tip or tip filter.
  5. Broken drive belt Replace belt.
  6. Displacement pump rod seized by dry paint Service pump. See page 14.
  7. Connecting rod worn or damaged Replace. See page 7.
  8. Drive housing worn or damaged Replace. See page 8.
  9. Electrical power not energizing clutch field Check wiring connections. See page 20. Reference control board diagnostics. See page 13. With pressure control switch ON and pressure turned to MAXIMUM, use a test light to check for power between clutch terminals on control board. Remove black clutch wires from control board and measure resistance across wires. At 70 _ F, the resistance must be between 1.7 ± 0.2 Ω ; if not, re- place pinion housing. Have pressure control checked by authorized Gra- co dealer.
  10. Clutch worn or damaged Service. See page 9.
  11. Pinion assembly worn or damaged Service. See page 9.

From 308864 rev H

Pump output low
  1. Strainer (31) clogged Clean.
  2. Piston ball (25) not seating Service piston ball check. Manual 308798.
  3. Piston packings worn or damaged Replace packings. Manual 308798.
  4. O-ring (227) in displacement pump is worn or damaged Replace o-ring. Manual 308798.
  5. Intake valve ball not seating properly Clean and service. Manual 308798.
  6. Engine speed is too low Increase throttle setting. See Manual 308863.
  7. V- -belt slipping Tighten V- -belt with clamp (101). Adjust clamp until it takes 15 lb of force to lock clamp down.
  8. Clutch worn or damaged Replace. See page 9.
  9. Pressure setting is too low Increase pressure. Manual 308863.
  10. Fluid filter (318), tip filter or tip is clogged or dirty Clean filter. Manual 308863 or 309091.
  11. Large pressure drop in hose with heavy materials Use larger diameter hose and/or reduce overall length of hose. Use of more than 100 ft of 1/4 in. hose significantly reduces performance of sprayer. Use 3/8 in. hose for optimum perfor- mance (50 ft minimum).

From 308864 rev H

Excessive paint leakage into throat packing nut
  1. Throat packings worn or damaged Replace packings. Manual 308798.
  2. Displacement rod worn or damaged Replace rod. Manual 308798.

From 308864 rev H

Spitting from gun
  1. Air in fluid pump or hose Check for loose connections at pump intake and tighten. Then prime pump. See Startup , Manual 308863.
  2. Tip partially clogged Clear.
  3. Fluid supply is low or empty Refill and prime pump. See Startup , Manual 308863. Check fluid supply often to prevent running pump dry.

From 308864 rev H

High engine speed at no load
  1. Worn engine governor Replace or service engine governor

From 308864 rev H

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