Paint Sprayer Clogging or Spitting? Troubleshooting Guide

When Your Sprayer Won't Spray Properly

Paint sprayers are brilliant when they work and infuriating when they don't. Clogging, spitting, uneven spray - these problems ruin finishes and waste time. Here's how to fix them.

Common Sprayer Problems

Clogging/blocked nozzle:

• Spray pattern weak or uneven
• Paint not coming out despite motor running
• Requires excessive pressure

Spitting/spattering:

• Bursts of paint instead of smooth spray
• Air bubbles in the paint
• Uneven, orange-peel finish

Tails or heavy spots:

• More paint at edges of spray pattern
• Drips and runs in certain areas

Cause 1: Dried Paint in the System

The most common problem. Paint dries in the nozzle, filters, or lines.

Solution:

1. Remove and soak nozzle in appropriate solvent (water for latex, thinner for oil)
2. Use a soft brush to clean all passages
3. Check and clean filters - often forgotten
4. Run solvent through the entire system
5. Inspect tip for wear or damage

Prevention:

• Clean thoroughly immediately after every use
• Don't leave paint sitting in the sprayer
• Store with pump protector fluid

Cause 2: Wrong Paint Viscosity

Paint too thick or too thin causes problems.

Too thick:

• Clogs nozzle
• Motor strains
• Poor atomisation (orange peel)

Too thin:

• Runs and drips
• Poor coverage
• May not atomise properly

Solution:

• Check paint manufacturer's spraying recommendations
• Use viscosity cup to test thickness
• Thin paint to recommended consistency
• Different sprayer types need different viscosity

Cause 3: Wrong Nozzle/Tip Size

Each paint type needs the right tip.

• Stains and sealers: smaller tips (0.011-0.013")
• Latex paints: medium tips (0.015-0.017")
• Primers and heavy paints: larger tips (0.019-0.023")

Using wrong size causes poor spray pattern, clogging, or excessive wear.

Cause 4: Air Leaks

Air getting into the system causes spitting.

Check for:

• Loose connections in suction line
• Damaged O-rings or seals
• Cracked suction tube
• Paint level too low (sucking air)

Solution:

• Tighten all connections
• Replace damaged seals
• Keep paint level topped up
• Prime the system properly before use

Cause 5: Worn Components

Sprayer parts wear out with use:

• Worn tip: Pattern becomes irregular, more paint at edges. Tips have a rated lifespan.
• Worn packings: Pressure loss, leaks at pump
• Worn filters: Reduced flow, contamination reaching tip

Replace wear parts regularly - they're consumables.

Cause 6: Contaminated Paint

Debris in paint causes clogging.

Solution:

• Always strain paint before use
• Check filters are clean
• Don't use old, skinned paint
• Keep paint containers closed

Systematic Troubleshooting

Work through in order:

1. Is the paint the right consistency and strained?
2. Are all filters clean?
3. Is the tip the right size and in good condition?
4. Are there any air leaks?
5. Is the system properly primed?
6. Are packings and seals in good condition?

Maintenance Schedule

After every use:

• Full clean with appropriate solvent
• Run until solvent comes out clean
• Clean tip and filters

Regularly:

• Inspect tip for wear
• Check and replace filters
• Inspect hoses for damage
• Lubricate as per manufacturer

The Bottom Line

Most sprayer problems come down to cleanliness and correct setup. Clean properly after every use, use the right tip and paint consistency, and replace wear parts regularly. A well-maintained sprayer is a reliable sprayer.