INSTRUCTIONS–PARTS LIST This manual contains important warnings and information. READ AND RETAIN FOR REFERENCE 308–646 Rev. B Supercedes Rev. A ELECTRIC, 120 VAC Performance 390 Airless Paint Sprayer 2750 psi (195 bar) Maximum Working Pressure Model 231–553, Series A Complete sprayer with hoses, gun, RAC IV DripLess Tip Guard and SwitchTip GRACO INC. P.O. BOX 1441 MINNEAPOLIS, MN COPYRIGHT 1996, GRACO INC. Graco Inc. is registered to I.S.
Table of Contents Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Component Identification and Function . . . . . . . . . . . 5 Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Startup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Shutdown and Care . . . . . . . . . . . . . . . . . . . . . . . . . . .
WARNING WARNING INJECTION HAZARD Spray from the gun, leaks or ruptured components can inject fluid into your body and cause extremely serious injury, including the need for amputation. Fluid splashed in the eyes or on the skin can also cause serious injury. Fluid injected into the skin is a serious injury. The injury may look like just a cut, but it is a serious injury. Get immediate medical attention. Do not point the gun at anyone or at any part of the body.
WARNING WARNING EQUIPMENT MISUSE HAZARD Equipment misuse can cause the equipment to rupture or malfunction and result in serious injury. INSTRUCTIONS This equipment is for professional use only. Read all instruction manuals, tags, and labels before operating the equipment. Use the equipment only for its intended purpose. If you are not sure, call your distributor. Do not alter or modify this equipment. Check equipment daily. Repair or replace worn or damaged parts immediately.
Component Function and Identification N C B A H E K 05963 G M D L F J 05993 Fig. 1 A Motor DC motor, 120 Vac, 15A, 1 phase B Drive Assembly Transfers power from DC motor to the displacement pump C Pressure Adjusting Knob Controls fluid outlet pressure D ON/OFF Switch Power switch that controls 120 Vac power to sprayer E Fluid Outlet Hose and spray gun is connected here F Displacement Pump Pressurizes fluid to be sprayed through spray gun G 50 ft (15 m) Main Hose 1/4 in.
Setup 2. Fill the wet–cup (102). Pry off the wet-cup seal. Fill the cup 1/3 full with Graco Throat Seal Liquid (TSL), supplied. Install the wet-cup seal. WARNING If you supply your own hoses and spray gun, be sure the hoses are electrically conductive, that the gun has a tip guard, and that each part is rated for at least 2750 psi (195 bar) Working Pressure. This is to reduce the risk of serious injury caused by static sparking, fluid injection or over-pressurization and rupture of the hose or gun. 3.
Operation How to use the gun trigger safety 1 Open or drain, position When engaged, the gun safety latch prevents the gun from accidental triggering. See Fig. 3. 2 Closed, or spray position WARNING INJECTION HAZARD If the gun still sprays when the gun trigger safety is locked, repair the gun. See manual 308–235, supplied. 1 2 1 Gun safety latch shown engaged 2 Gun safety latch shown disengaged 04646 Fig. 4 How to use the pressure control. 1 2 Fig.
Operation How to use the RAC IV tip guard. WARNING INJECTION HAZARD To reduce the risk of serious injury, whenever you are instructed to relieve pressure, follow the Pressure Relief Procedure on page 9. 1 1 Tip handle shown in spraying position. 2 Turn handle 180 , trigger gun to clear clog Fig. 6 2 04647 How to remove a tip clog. The tip guard alerts you to the risk and helps prevent placing any part of the body close to the spray tip.
Startup WARNING INJECTION HAZARD The system pressure must be manually relieved to prevent the system from starting or spraying accidentally. Fluid under high pressure can be injected through the skin and cause serious injury. To reduce the risk of an injury from injection, splashing fluid, or moving parts, follow the Pressure Relief Procedure whenever you: NOTE: If this is a first-time startup, flush the sprayer. See page 13. NOTE: Refer to Fig.
Startup b. If more coverage is needed, use a larger tip rather than increasing the pressure. WARNING FIRE AND EXPLOSION HAZARD To reduce the risk of static sparking and splashing when priming or flushing the system, hold a metal part of the gun firmly to the side of a grounded metal pail before triggering the gun. 6. To prime the hose, lower the pressure to reduce splashing. Hold a metal part of the gun firmly against and aimed into a grounded metal pail. See the preceding WARNING.
Startup 32 1 1/4 npsm(m) fluid outlet 2 Do not install any shutoff device here 3 Rotate clockwise to increase pressure 4 Shown in closed or spray position 5 Fill 1/3 full with TSL 33 74 3 2 1 64 28 52 4 67 102 5 05993 Fig.
Shutdown and Care WARNING WARNING INJECTION HAZARD To reduce the risk of serious injury, whenever you are instructed to relieve pressure, follow the Pressure Relief Procedure on page 9. Shutdown and Care INJECTION HAZARD See the warning section INJECTION HAZARD on page 3 for information on the hazard of using damaged hoses. 1 1. Check the packing nut/wet-cup daily (102). Relieve pressure first.
Flushing When to Flush 1. Before using a new sprayer: flush out the oil which was left in to protect pump parts. Before using water-base paint: flush with mineral spirits followed by soapy water, and then a clean water flush. Before using oil-base paint: flush with mineral spirits only. 2. Changing colors: flush with a compatible solvent such as mineral spirits or water. 3. Changing from water-base to oil-base paint: flush with warm, soapy water, and then mineral spirits. 4.
Troubleshooting WARNING INJECTION HAZARD To reduce the risk of serious injury, whenever you are instructed to relieve pressure, follow the Pressure Relief Procedure on page 9. Basic Problem Solving Check everything in the troubleshooting table before disassembling the sprayer. TYPE OF PROBLEM WHAT TO CHECK If check is OK, go to next check WHAT TO DO When check is not OK, refer to this column Fluid pressure 1. Check pressure control knob setting.
Basic Problem Solving TYPE OF PROBLEM WHAT TO CHECK If check is OK, go to next check WHAT TO DO When check is not OK, refer to this column Electrical (continued) 5. Check motor armature commutator for burn spots, gouges and extreme roughness. Remove motor cover and brush inspection plates to check. See page 20. 5. Remove motor and have motor shop resurface commutator if possible. See page 26. 6. Check motor armature for shorts using armature tester (growler) or perform motor test. See page 18. 6.
Intermediate Problem Solving TYPE OF PROBLEM WHAT TO CHECK If check is OK, go to next check WHAT TO DO When check is not OK, refer to this column Low output (continued) 3. Release gun trigger. Observe resting position of 3. If pump consistently comes to rest with pump rod (107). rod (107) fully extended, the piston packings and/or piston valve may be worn. Service the pump. See page 22. 4. Check electrical supply with volt meter. Meter should read 105–125VAC. 4.
Intermediate Problem Solving TYPE OF PROBLEM WHAT TO CHECK If check is OK, go to next check WHAT TO DO When check is not OK, refer to this column Spray Pattern Variations 1. Spray tip worn beyond sprayer pressure capability. 1. Replace spray tip. NOTE: A smaller size tip will provide longer life. 2. Check transducer (29) for wear or damage. 2. Replace transducer. See page 31. 3. Check pressure control (64) for smooth operation. 3. Replace pressure control. See page 30. 4.
Motor Test WARNING INJECTION HAZARD To reduce the risk of serious injury, whenever you are instructed to relieve pressure, follow the Pressure Relief Procedure on page 9. B For checking armature, motor winding and brush electrical continuity. Setup A Remove the drive housing. See page 28. This is to ensure that any resistance you notice in the armature test is due to the motor and not to worn gears in the drive housing. Remove the motor brush inspection covers (A). See Fig. 12. 04652 Fig.
General Repair Information WARNING INJECTION HAZARD To reduce the risk of serious injury, whenever you are instructed to relieve pressure, follow the Pressure Relief Procedure on page 9. Tool List WARNING HOT SURFACE HAZARD During operation, the motor and drive housing become very hot and could burn your skin if touched. Flammable materials spilled on the hot, bare motor could cause a fire or explosion CAUTION These are the tools required to service all parts of the sprayer.
Motor Brushes NOTE: Replace brushes when worn to about 0.5 in. (12.5 mm). Always check both brushes. Brush Repair Kit 236–967, which includes spring clip 112–766, is available for motors manufactured by Pacific Scientific. 1 Motor lead; do not disconnect 2 Minimum 0.5” (12.5 mm) 3 Included in Brush Repair Kit 236–967 2 NOTE: Replacement brushes may last only half as long as the original ones.
Motor Brushes 9. Test the brushes. a. Remove the pump connecting rod pin (17). See Fig. 18, page 22. b. With the sprayer OFF, turn the pressure control knob fully counterclockwise to minimum pressure. Plug in the sprayer. c. Turn the sprayer ON. Slowly increase the pressure until the motor is at full speed. d. Inspect the brush and commutator contact area for excessive arcing. Arcs should not trail or circle around the commutator surface.
Displacement Pump Repair WARNING INJECTION HAZARD To reduce the risk of serious injury, whenever you are instructed to relieve pressure, follow the Pressure Relief Procedure on page 9. NOTE: Packing Repair Kit 235–703 is available. Reference numbers of parts included in the kit are marked with an asterisk, i.e., (121*). For the best results, use all the new parts in the kit, even if the old ones still look good. 2. Align the hole in the rod (107) with the connecting rod assembly (15).
Displacement Pump Repair Intake valve repair (See Fig. 17) 1. Remove the suction hose. See Step 2, Removing the pump. 2. Unscrew the intake valve (118). Remove the o-ring (119*), ball guide (120), stop pin (122*) and ball (121*) from the valve. 3. Clean and inspect the parts for wear or damage. Replace parts as needed. Use a new o–ring (119*). If no further service is needed, reassemble the pump. Disassembling the pump (See Fig. 19.) 1.
Displacement Pump Repair 3. Tighten the nut (110) onto the piston valve (108) to 5 in-lb (0.57 N.m). See Fig. 20. NOTE: Note the alignment of the piston (108) to the nut (110). Maintain this alignment through Step 8. Torque to 5 in–lb (0.57 N.m) 107 Apply one drop of sealant to these threads *109 110 4. Clean all residue from the piston valve threads. Apply one drop of adhesive, supplied, to the threads. 5. Place the ball (109*) on the piston valve (108). See Fig. 20.
Displacement Pump Repair 11. Place a new o-ring (116*) firmly in the cylinder groove. See Fig. 22. 15. Torque the cylinder jam nut (117) to 73 ft-lb (98 N.m). See Fig. 22. 12. Coat the piston rod and packings with oil. Carefully slide the assembly into the top of the cylinder (115). See Fig. 22. 16. Install the pump. See page 22. 13. Put the manifold upside down in a vise. Fully thread the jam nut (117) onto the cylinder (115). Guide the rod/cylinder assembly down through the manifold (101).
Motor 8. Remove the two screws (46) and lift the motor off the base (66). WARNING INJECTION HAZARD To reduce the risk of serious injury, whenever you are instructed to relieve pressure, follow the Pressure Relief Procedure on page 9. 9. Align the new motor with the base and reinstall the screws (46). 10. Assemble the drive housing to the motor. Follow steps 8 to 11 on page 28. 11. Connect the wires in the junction box. Refer to Fig. 27 on page 27. Install the junction box. NOTE: See Fig.
Motor Start Board WARNING INJECTION HAZARD To reduce the risk of serious injury, whenever you are instructed to relieve pressure, follow the Pressure Relief Procedure on page 9. 5. Install the new cord (50) in the reverse order of disassembly. 6. Install the junction box. Be sure no leads are pinched against the motor or by the motor start board. Also be sure the gasket (89) is installed. On/Off Switch NOTE: See Fig. 27 for this procedure. NOTE: See Fig. 27 for this procedure. 1. Relieve pressure. 1.
Drive Housing, Connecting Rod, Crankshaft WARNING CAUTION INJECTION HAZARD To reduce the risk of serious injury, whenever you are instructed to relieve pressure, follow the Pressure Relief Procedure on page 9. NOTE: Inspect parts as they are removed. Replace parts that are worn or damaged. 1. Remove the displacement pump. See page 22. Do not allow the gear (16) to fall; it may stay attached to the drive housing or to the motor.
Drive Housing, Connecting Rod, Crankshaft 1 64 4 12a Torque to 80 in–lb (9 N.m) 2 Quantity of three 3 Quantity of one 4 Apply a total of 3 fl. oz.(29 cc) of grease to gears. 12 31 A 47 59 56 11 13 Fig.
Pressure Control WARNING INJECTION HAZARD To reduce the risk of serious injury, whenever you are instructed to relieve pressure, follow the Pressure Relief Procedure on page 9. 7. Loosely install the screws (63) and then torque them to 21 in–lb (2.4 N.m). 8. Install the front cover (13). Connect the harness (A) to the motor start board (47). 9. Install the junction box. Be sure no leads are pinched against the motor or by the motor start board. NOTE: See Fig. 30 for this procedure.
Pressure Transducer WARNING INJECTION HAZARD To reduce the risk of serious injury, whenever you are instructed to relieve pressure, follow the Pressure Relief Procedure on page 9. NOTE: See Fig. 31 for this procedure. 29 1. Remove the displacement pump. See page 22. 2. Use a pull–twist motion to remove the transducer (29) from the pump manifold (101). 101 3. Clean paint residue from the hole in the manifold; do not scratch the surface of the hole. 4.
Drain Valve Repair WARNING INJECTION HAZARD To reduce the risk of serious injury, whenever you are instructed to relieve pressure, follow the Pressure Relief Procedure on page 9. 42a 42b 1 1 42d 42c 3 Apply thread sealant 2 Apply grease to face of base 3 Torque into pump manifold to 185 in–lb (21 N.m) 4 Handle shown in closed position 2 42 2. If replacing the gasket (42a) or seat (42b), pry out the gasket. NOTE: Whenever the gasket (42a) is removed, replace it with a new one. 3.
Displacement Pump Parts Drawing and List Model 236–787, Series A Includes items 101 to 127 Ref No. 101 102 103* 104* 105* 106* 107 108 109* 110 111* 112* 113* 114* 115 116* 117 118 119* 120 121* 122* 123 124* 127 Part No.
Sprayer Parts Drawing Model 231–553, Series A HOSE AND GUN NOT SHOWN IN PROPORTION TO SPRAYER 74 1 Label 2 See detail on page 31 67 39 30 REF 33 4e REF 32 1 24 19 4 64 4a 29 16 12b 12 4f 79 63 6 11b 4g 12a 1 1 89 19 15 11a 35 13 18 OUTSIDE LABEL 17 2 11 66 50 14 INSIDE LABEL 56 42a 42b 42d 42c 28 31 21 20 34 36 32 33 23 46 42 43 44 45 37 38 25 O4658
Sprayer Parts List Model 231–553, Series A Includes items 3 to 89 as listed below Ref. No. Part No. 4{ 236–965 Description Qty. MOTOR KIT Includes items 4a to 4g .BALL, sst, 1/4” dia. .TERMINAL, flat, 1/4” (f), 18 awg .TERMINAL, 3/16” (m), 16 awg .TERMINAL, 3/16” (f) .LABEL, DANGER, French .LABEL, DANGER, English .LABEL, WARNING, electric shock LOCKWASHER, 1/4” 1 1 2 1 1 1 1 1 3 1 4a. 4b. 4c. 4d. 4e.Y 4f.Y 4g.
Technical Data Power Requirements . . . . . . . . . . . . . . . . . . . . 120 VAC,60Hz, 1 phase, 15 amp minimum Generator . . . . . . . . . . . . . . . . . . . . . . . . . . 3000 Watt minimum Working Pressure Range . . . . . . . . . 0–2750 psi (0 – 195 bar) Motor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1/2 hp Cycles/Gallon (liter) . . . . . . . . . . . . . . . . . . . . . . . . . . . 620 (164) Delivery . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.
