The Anatomy of a Graco LineLazer 3400 — Features, Setup & a How-To Guide You NEED to Master Your Line Marking Unit

Three things: compact, lightweight, and maneuverable. 

The Graco LineLazer 3400 is the ultimate entry-level line marking machine. Designed for small to medium-sized projects, this line marker offers a perfect balance of bulletproof reliability, simple operations, and straightforward functionality. Ideal for car parks, bike paths, stencils, or as a versatile addition to your existing fleet.

In this comprehensive guide, we break down the Graco LineLazer 3400, how to master setup, operation and clean-up. We give you all of the preventative maintenance tips and tricks, and how best to keep your LineLazer off our service bench!

So, What Is the Graco LineLazer 3400?

The Graco LineLazer 3400 is a compact, petrol-powered line marker built for versatility. Powered by a Honda petrol motor, it features a single manual spray gun (Graco Silver Plus). If you’re familiar with Graco’s paint airless sprayers, the setup is near-identical - just with a robust-built frame, and purposefully designed controls for marking lines.

That means you’ll find the usual airless sprayer features and components: manifold filter, pump prime/spray valve, pressure gauge, spray tips & guards, now paired with a Honda petrol powered engine.

Diving deeper into the standard inclusions with the LineLazer 3400, contain the following:

• Extra LineLazer & Rac 5 Spray Tips for varying line widths (LL5319 and 286517)

• Rac 5 Tip Guard

• ¼” x 15M Airless Line Marking Hose

• and Graco’s Silver Plus striping Gun

The real magic is how easy it is to use - since famously Graco designed this machine with efficiency, performance, and simplicity in mind.

Key Features & Controls

Handlebars:

• Left trigger: Controls the front wheel. Engage the trigger for marking curves and turns; release it to lock in a straight line.

• Right trigger: Controls the spray gun via the gun cable.
  

SAFETY TIP: Keep the brake engaged when not in use so it doesn’t roll off (yes, it happens). Relieve pressure by spraying into a waste pail, then switch back to prime once pressure is relieved.

Gun Arms:

Adjustable with incremental markings, the gun arms can be configured to match nearly any measurement required.

¼” x 15m Hose:

Great for stencil work or detailed spraying away from the main LineLazer.

SAFETY TIP: This machine operates at high pressure. Skin injection injuries are serious. Always engage the trigger lock when the gun is not in use.

Prime & Spray

Now that you know the parts, let’s talk about setup. Proper prep - priming, spraying, cleaning - is critical for longevity and performance To get started, assemble the parts and flush the unit with water. (We’ve also got an indepth video walkthrough on this one)

Tip Cheat Code:

• Tip facing the gun = flush mode (to clear blockages)

• Tip rotated = spray fan mode
  
  

To prime the unit, ensure the paint flows through, eliminating any air in the system, which allows for consistent pressure and smooth application. You’ll need to test different pressure settings depending on the paint and tip - use a piece of cardboard to dial it in. Always start at the lowest pressure possible, and adjust accordingly to achieve a sharp line.

Quick Start Checklist (Save this!)

✅ Motor Fuel On
✅ Choke On
✅ Pull to Start
✅ Choke Off
✅ Increase Motor Speed
✅ Turn the Pump Switch ‘On’ at the Handlebars
✅ Ensure the Prime Switch is in the ‘downward’ position - increase pressure
✅ Prime and run the paint through the unit
✅ Switch to spray and dial in the right pressure (starting slow and increasing as needed)
✅ Take off the brake, and start striping!

Quick Troubleshooting & Storage

You’ve invested a lot in this machine and proper maintenance will keep it performing for years.

It’s powered by a Honda petrol engine, so general engine maintenance applies. Got fuel, air, and spark? Is the machine even switched on? (Yes, we’ve all missed that one at some point in our striping lives.)

Common Pressure Issue: If your unit suddenly loses pressure after a break, there might be dried paint (paint skin) in the lower housing of the pump. Typically, this skin will sit around the Seat and Check Ball.
Quick fix: Switch to prime, then tap the lower pump housing gently with a mallet as the pump is running at a low pressure. This usually unsticks the ball and allows the pump to cycle paint through the drain tube - effectively allowing the unit to prime again.

Maintenance Must-Haves: Throat Seal Liquid (TSL) & Pump Armour

Graco nailed it with these two:

TSL (Throat Seal Liquid):
Add a few drops before every use. It prevents paint from drying on the piston rod and causing wear in the pump packings.

Pump Armour:
After cleaning, prime the Pump Armour through the unit before storage. Add a neat amount of Pump Armour in water - or prime undiluted if storing for long periods of time. This essential step will protect your machine from corrosion and avoid expensive repairs down the track.

Conclusion? THE Ideal Entry-Level Linemarking Unit

The Graco LineLazer 3400 proves that less can truly be more. It’s easy to use, simple to maintain, and highly capable for its price point.

For line marking contractors, both existing or new, councils, or teams looking to streamline their line marking operations without a steep learning curve, this unit is a no-brainer.

Whether you’re a seasoned pro or new to the game, the 3400 delivers excellent value and dependable performance.

Want to see it all in action?  Check out our full video walkthrough: Watch now

If you can’t handle the fumes of a petrol motor - also check out the LineLazer 3400’s brother-machine, the battery-driven LineLazer ES 500. More of the same, with the benefits of less noise, no fumes, and smooth spraying.