Kobalt 40V Backpack Sprayer KBSP 1040B-03 User Guide
Quick guide for the Kobalt 40V Backpack Sprayer (KBSP 1040B-03). Learn how to assemble, operate, clean, and troubleshoot your sprayer safely.
Table of contents
Manual images
Click an image to enlargeQuick guide from the manual
This guide provides essential information for operating the Kobalt 40V Backpack Sprayer (KBSP 1040B-03). Always read the full manual before use. Key steps include ensuring the battery is charged, the tank is filled with thin, water-like chemicals, and the nozzle is adjusted for your desired spray pattern.

Safety Information
Warning: Always wear safety goggles or glasses with side shields and a full-face shield when needed. This product may contain chemicals known to cause cancer or reproductive harm. Do not use in the rain, do not spray toward electrical outlets, and never spray directly against skin. Keep children and bystanders away during operation.
Assembly Instructions
To Install/Remove Battery Pack:

- Ensure the ON/OFF switch (D) is in the OFF “O” position.
- Open the battery bay cover (C).
- Align the mounting grooves on the battery pack with the raised ribs in the sprayer’s battery compartment.
- Slide the battery pack into the sprayer until it snaps into position.
- To remove, press the battery-release button and slide the pack out.
Operating Instructions



Connecting the Spray Wand and Hose
- Wand: Ensure the O-ring is in place inside the end cap. Thread the end cap of the spray wand (G) onto the handle (H) and tighten securely.
- Hose: Thread the end cap of the hose (F) onto the end of the handle (H) and hand-tighten.
Filling the Tank
Only use thin, water-like liquids. Do not overfill.
- Remove the battery pack.
- Unscrew the tank cap (A).
- Fill the tank (B) with the desired amount of water and chemical.
- Screw the cap (A) back on securely.
Spraying
- Turn the ON/OFF switch (D) to the ON “I” position.
- Depress the trigger on the handle (H) to start the flow.
- Use the Lock-On Trigger by depressing the trigger and sliding it forward for extended spraying. Slide it backward to release.
- Adjust the nozzle by loosening it for a stream or tightening it for a fan spray.
Care and Maintenance
Cleaning:

- Drain any remaining liquid from the tank.
- Fill the tank one-third full with clean water and spray until empty. Repeat if necessary.
- Clean the exterior with a soft, dry cloth. Never use detergent or alcohol.
Cleaning the Nozzle: If the nozzle becomes obstructed, unscrew it from the wand and push a small wire through the cross holes to clear debris. Rinse with clean water and reinstall.
Troubleshooting
If the sprayer does not work, check for low battery capacity or if the unit is overheated. If liquid leaks from joints, ensure end caps are tightened or replace the O-ring if damaged.
Manufacturer information
Kobalt
Practical help
Common problems
Check if the battery is charged or if the battery/sprayer is too hot. Allow to cool if necessary.
Tighten the end caps. If the leak persists, check if the O-ring is cracked or damaged and replace it.
Before use
- Inspect the tool for any damage or missing parts.
- Ensure the battery is fully charged.
- Verify the O-ring is in place inside the wand end cap.
- Ensure the ON/OFF switch is in the OFF position before inserting the battery.
- Check that the tank cap is tightened securely.
Specs in practice
- Rated power input
- 40V d.c.
- Tank Capacity
- 4 gal (15L)
Images and diagrams
- The parts diagram identifies the tank, battery bay, harness, hose, spray wand, and trigger handle.
- Battery installation involves aligning the grooves and sliding the pack until it snaps.
Model compatibility
- Compatible with Kobalt 40V batteries: KB 240-03, KB 440-03, KB 640-03.
- Use only the KRC 840-03 charger.
Manual page author
Michael Turner
Technical manual editor
Reviews PDF manuals for structure, safety notes, and practical product details so readers can find the right information quickly.