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Airless Paint Sprayer Trouble Shooting Guide

 

Problem

Cause

Solution
There is spitting from the gun. 1. The fluid supply is low or empty. Refill the supply container.

 		 2. Air entrapped in the fluid pump of the hose. Check for loose connections on the siphon assembly, tighten, then reprime pump.
Paint leaks into the wet cup. 1. The wet cup is loose. Tighten just enough to stop leakage.
  2. The throat packings are worn or damaged. Replace the packings.
  3. Piston rod worn. Replace piston rod.
The motor operates, but the paint pump doesn't. 1. The pressure setting is too low. Increase the pressure.
  2. The displacement is seized by dried paint. Service the pump.
The motor and displacement pump operates, but paint pressure is too low, or none. 1. The pressure setting is too low. Increase the pressure.
  2. The tip or gun filter is clogged. Remove the tip and/or filter and clean them.
  3. Tip is worn. Replace tip.
  4. The fluid displacement pump filter (if used) is clogged. Clean the filter.
  5. There is a large pressure drop in the fluid hose. Use a larger diameter hose.
The displacement pump operates, but the output is too low on the down stroke or both strokes. 1. The lower check valve ball is not seating properly. Service the lower check valve ball check.
The displacement operates, but the output is too low on the upstroke. 1. The upper check valve ball is not seating properly. Service the upper check ball valve.
  2. The lower packings are worn or damaged. Replace the packings.
The displacement pump operates but the pressure is too low. 1. Tip too large. Use smaller tip.
  2. Long extension cord causes power drop. Use less extension cord.
Motor stops.
 		 Reset overload switch.
The displacement pump operates but the unit does not prime. 1. Upper or lower ball is stuck or obstructed. Service upper and lower check ball valve.
  2. Unit hose air leak (bubbles blowing out bypass hose.) Inspect suction hose for holes, if so equipped. Ensure suction nut is tight and lower ball cage O-ring is not worn.
Unit does not run. 1. Thermal breaker tripped. Press re-set button
  2. Electrical failure Contact local Airlessco Service Center.
Machine does not start. 1. Control Settings Step 1. Ensure the the ON-OFF toggle switch is in the "ON" position and that the Pressure Control Knob is fully CW (maximum pressure). Also check that the unit is plugged in.

Step 2. Remove the electrical cover on the bottom of the machine. Check if the green power light on the board is lit. If the the light is "OFF", proceed to Step 3. If the light is "ON", go to step 7.
  Power Source Use a multi-meter to check
Unit will not prime. 1. Dried out piston packings and stuck ball valves. Remove siphon tube and feel lower ball check to be sure it is free to move off its seat. Place full cup of paint thinner over end of fluid section and turn on pump.
  2. Pump inlet screen plugged or air in pump or hose. Remove and clean.
 
 		 Hold gun trigger in open position and run unit about 10 seconds until air is purged.
 
 		 Check for siphon tube leak.
  3. Packings worn. Replace.
  4. Fluid too viscous. Prime pump with compatible solvent. Bring up to pressure, carefully remove pump from solvent container and immerse inlet tube into heavy material to be sprayed. With nozzle tip removed, trigger gun until heavy material appears aat gun. Replace nozzle tip and you're ready to spray.
  5. Siphon tube clogged. Remove and clean.
  6. Siphon tube air leak. Check connection and seal.
  7. Clogged tip. Relieve pressure, remove tip and clean.
Unit will not build or maintain pressure. 1. Pressure adjusting knob not properly set. Adjust to increase pressure.
  2. Pump inlet strainer dirty. Clean or temporarily remove.
  3. Valve balls or seats worn or dirty. Replace or clean.
  4.Air in pump or hose. Hold gun trigger in open position and run about 10 seconds until air is purged.
 
 		 Check for siphon tube leak.
  5. Packings worn. Replace.
  6. Worn spray tip. Replace.
  7. Internal leakage. With gun trigger closed, allow unit to pump up to pressure and shut off. If pump momentarily starts, internal leak is indicated and fluid section rebuild is necessary.
  8. Fluid leak. Check for external leaks including hydraulic fittings attached to pressure control housing.
  9. Fluid too viscous. Consult manufacturers recommendations on paint container label.
  10. Too large a spray tip. Change tip.
Fluid leakage out relief hole at pressure control. 1. Worn "O" Rings. Repack or replace transducer.
Fluid leakage at upper end or fluid section. 1. Upper packings. Relieve pressure and tighten packing take up nut or replace packings.
  2. Piston rod worn Replace.
Bad spray pattern. 1. Too large a tip size Change to a smaller tip size
  2. Pressure adjustment wrong. Adjust pressure control knob.
  3. Insufficient fluid delivery. Clean all strainers and filters in system.
  4. Fluid too viscous. Add solvent to fluid according to manufactures recommendations.
Unit lacks power. Pressure adjustment low. Increase.
  Improper voltage supply. Reconnect input voltage for 115 VAC
Blown fuses at pump. 1. Excessive pressure. Have service center recalibrate the pressure control.
  2. Excessive extension cord length or improper wire gauge. Use #12 gauge wire or larger up to maximum of 200 feet. For additional length, more airless hose may be used.
Unit will not prime. 1. Dried out packings or stuck valve balls. Remove siphon tube and feel lower ball check to be sure it is free to move off its seat. Place full cup of paint thinner over end of fluid section and turn on pump.
  2. Stuck valve balls.
 
  3. Pump inlet screen plugged. Remove and clean.
  4. Air in pump or hose. Hold gun trigger in open position and run unit about 10 seconds until air is purged.
 
 		 Check for siphon tube leak.
  5. Packings worn. Replace.
  6. Fluid too viscous. Prime pump with compatible solvent. Bring up to pressure, carefully remove pump from solvent container and immerse inlet tube into heavy to be sprayed. With nozzle tip removed, trigger gun until heavy material appears at gun. Replace nozzle tip and you're ready to spray.
  7. Siphon tube clogged. Remove and clean.
  8. Siphon tube air leak. Check connection and seal.
  9. Clogged tip. Relieve pressure, remove tip and clean.
Unit will not build or maintain pressure. 1. Pressure adjusting knob not properly set. Adjust to increase pressure.
  2. Pump inlet strainer dirty. Clean or temporarily remove.
  3. Valve balls or seats worn or dirty. Replace or clean.
  4. Air in pump or hose. Hold gun trigger in open position and run until air is purged.
  5. Packings worn. Replace.
  6. Worn spray tip. Replace.
  7. Internal leakage. With gun trigger closed, allow unit to pump up to pressure and shut off. If pump momentarily starts, internal leak is indicated and fluid section rebuild is necessary.
Paint will not shut off at spray tip of airless gun. 1. Seat in the gun dirty. Trigger gun several times under pressure.
  2. Needle stop nut too tight. Loosen the stop-nut.
  3. Worn valve assembly. Replace valve assembly.
Airless pump motor doesn't turn over. 1. No power. Check house electrical fuse (use at least a 15 amp).
  2. Thermal overload switch.
 
  3. Unit under pressure. Turn bypass valve to prime.
  4. Defective switch or wiring. Replace switch, check wiring; replace if necessary.
Gun will not spray. 1. Trigger safety on. Disengage trigger stop.
  2. Inline filter clogged. Clean or replace mesh filter.
  3. Adjustable tip clogged. Turn knob counterclockwise.
Spray pattern has "tails" or fingering. 1. Pressure too low. Increase pressure at pump.
  2. Material too thick. Thin per manufacturer's recommendation.
  3. Tip adjusted too wide. Reduce pattern size.
  4. Spray tip worn. Install new tip.
Distorted pattern 1. Plugged or worn tip Clean or replace tip.
Pump draws up paint but the pressure does not build up. 1. Bypass valve in "prime" position. Turn valve to spray.
  2. Air in hydraulic system. Bleed air from system.
  3. Pressure valve not adjusted or worn.
 
  4. Inlet valve worn. Replace.
  5. Low oil level. Check oil.
  6. Bypass valve clogged or worn. Clean or replace.
Pump draws up paint, pressure builds but drops when the gun is triggered. 1. Material too thick. Thin paint per manufacturer's recommendation.
  2. Bypass valve not shutting off. Clean or replace.
  3. Air in the paint. Check suction hose & connections.
  4. Air in hydraulics. Bleed.
  5. Tip orifice too large or worn. Adjust tip or replace strainer.
  6. Suction strainer clogged. Clean and replace.
  7. Inlet or outlet valve worn. Replace.
Spray tip keeps clogging. 1. Contamination in paint. Strain paint. Clean or replace filters.
  2. Paint dried in the spray tip. Keep tip moist when not spraying.
 
 		 Replace tip with adjustable tip.
Sprayer does not start up. 1. Sprayer not plugged in. Plug in.
  2. On-Off switch Off. Flip switch On.
  3. Blown fuse in circuit. Replace fuse.
  4. Low voltage at wall plug. Test power supply voltage.
  5. Bad On-Off switch. Take to authorized service center.
  6. Damaged motor cord or extension cord, or voltage too low.
 
  7. Motor problem. Take to authorized service center.
Sprayer starts up but does not draw in paint. 1. No paint or suction tube not totally immersed in paint. Add more paint. Immerse suction tube in paint.
  2. Suction filter clogged. Clean filter screen.
  3. Suction tube loose at inlet valve. Clean connection and tighten.
  4. Inlet valve stuck. Push valve with a pencil.
  5. Outlet valve is stuck, dirty or has worn out parts. Push the push button valve on the block to loosen or remove outlet and replace.
  6. Bypass knob in "Spray" position. Turn bypass knob to "Prime".
  7. Pressure knob in "Low" setting. Turn pressure knob to "High".
  8. Air in the hydraulic system. Bleed air out of the unit.
  9. Bypass Valve plugged. Remove to clean or replace. Take to service center.
  10. Suction tube problem. Check for air leaks. Replace if necessary.
  11. Inlet valve damage (neck).
 
No sound. 1. Not plugged in. Check plug & extension cord. Check motor switch
  2. House circuit breaker. Check breaker. Try another electrical outlet.
  3. Thermal overload switch tripped. Feel motor case. If hot, turn "off". Let cool & check motor case before starting.
Hums, but does not start or run correctly. 1. Pump under pressure. Turn bypass valve to prime.
  2. Incorrect voltage. Check house voltage.
  3. Extension cord. Maximum length 100' - 10 ga.
  4. Condenser. Replace. See service center.
Will not prime, has vacuum. 1.Suction filter clogged. Clean filter or replace.
  2. Air leak in suction set. Check connections. Clean and tighten.
  3. Suction head not submerged. Check. Add more paint.
  4. Paint too thick. Thin as recommended.
No Vacuum. 1. Bypass knob on "spray". Turn counterclockwise.
  2. Pressure knob on "low". Turn pressure knob clockwise.
  3. Inlet valve stuck. Remove suction hose. Press inlet valve with finger to free.
  4. Outlet valve stuck. Pour small amount of liquid in inlet valve to prime. If necessary, remove outlet plug and free the outlet ball.
  5. Air in oil system. Check oil level & bleed system.
  6. Inlet valve worn. Check and replace per manual.
  7. Outlet valve worn. Check and replace per manual.
  8. Oil in the paint? Replace diaphragm per manual.
Primes, but no pressure. 1. Suction filter. Clean filter or replace.
  2. Bypass valve on prime. Turn knob clockwise to "spray".
  3. Bypass vale leaking. Check for flow out o
  4.Air in oil system. Check oil and bleed system.
Low pressure. 1. Gun filter clogged. Clean or replace.
  2. Suction filter clogged. Clean or replace.
  3. Paint too thick. Thin as recommended.
  4. Outlet valve worn. Check & replace.
  5. Pressure valve worn. Reset pressure or replace.
Good pressure, but no spray. 1. Gun filter. Clean or replace.
  2. Tip clogged. Remove and clean.
Gun.
 
 
Drips paint with trigger released. 1. Dirt in gun valve. Disassemble & clean.
  2. Worn gun valve. Replace per gun manual.
Drips while spraying. 1. Spray tip worn. Replace.
Sprays uneven. 1. Dried paint in spray tip. Remove and clean.
  2. Spray tip worn. Replace.
Electric shock while spraying. 1. Pump not grounded. Check extension cord and house circuit.
  2. Metal object being painted not grounded. Attach ground wire to object.
Material will not shut off at spray tip of Airless Gun. 1. Ball or seat in gun dirty. Try triggering gun several times while under pressure.
  2. Diffuser seat worn. Replace Diffuser assembly.
  3. Needle assembly worn. Replace if necessary.
Airless gun will not spray. 1. No pressure at gun. Check pump for proper operation, check filter and strainer (clogged).
  2. Spay tip clogged. Clean tip with pointed needle and blow with compressed air.
Airless gun has tails in spray pattern. 1. Material pressure too low. Increase pressure at unit.
  2. Material too thick. Thin paint per manufacturer's recommendation.
  3. Spray tip worn. Replace.
Airless pump motor doesn't turn over. 1. No power. Check electrical fuse.
  2. Defective switch or wiring. Replace switch, check wiring; replace if necessary.
  3. Unit under pressure. Turn combination valve counterclockwise to positive stop.
  4. If the above problems cannot be corrected, the motor could be defective. Replace motor if necessary.
Airless pump does not draw paint. 1. Suction tube not totally immersed in paint. Add more paint.
  2. Suction tube loose and draws in air. Tighten clamp and fittings at inlet valve.
  3. Suction tube damaged. Replace if necessary.
  4. Suction strainer clogged. Clean or replace.
  5. Air in hydraulic system due to fluid level low in crankcase or due to shipment. Add 10W-30 oil to crankcase. Bleed air from system.
  6.