How to Change the Coolant in a 2018 Kawasaki KLR650

Shop parts for a 2018 Kawasaki KLR650 Dirt Bike.

Regular coolant changes are critical for keeping your 2018 Kawasaki KLR650 running cool, extending the life of your engine, and preventing corrosion in the cooling system. The KLR650's robust single-cylinder design means it is both durable and easy to service, but its liquid cooling system requires periodic attentionespecially if you take your bike off-road, where mud and debris can put extra strain on the radiator and cooling channels. Below you'll find a MotoSport-exclusive step-by-step guide to changing your coolant, along with notes tailored for KLR650 owners.

Before You Start: Tools and Materials

  • New, silica-free motorcycle coolant (avoid automotive coolants with silicates or phosphates; use products designed for aluminum engines)
  • Distilled water (for flushing)
  • Catching pan for old coolant
  • Clean rags and gloves
  • 10mm and 8mm socket or wrench set
  • Phillips screwdriver

Step 1: Preparation

  • Ensure the bike is cool before startingnever open the radiator cap on a hot engine.
  • Place the bike on level ground and secure with the kickstand or stand.
  • Remove side panels and, if desired, the seat for easier access to the radiator and hoses.

Step 2: Drain Old Coolant

  • Locate the radiator cap on the right side under the tank shroud, and the coolant drain bolt on the lower part of the water pump (left side engine cover).
  • Place the catch pan under the drain bolt. Remove the radiator cap to release system pressure.
  • Using the appropriate socket, remove the drain bolt and let the coolant fully drain.
  • Be sure to also drain the reservoir tank by disconnecting its hose or removing the tank and pouring out old coolant.

Step 3: Flush the System

  • Reinstall the drain bolt and tighten to spec.
  • Fill the radiator with distilled water. Reinstall the cap loosely.
  • Start the engine and let it idle for several minutes, then shut off and fully cool.
  • Remove the drain bolt and drain the rinse water.
  • Repeat this flush until the drained water runs clear (1-2 flushes are usually sufficient).

Step 4: Fill with Fresh Coolant

  • Reinstall and tighten the drain bolt.
  • Fill the radiator slowly with your chosen new coolant. Gently rock the bike to help air escape.
  • Fill the coolant reservoir up to the upper mark with coolant as well.
  • Reinstall both caps securely.

Step 5: Burp the System – Remove Trapped Air

  • Start the bike and let it idle until it reaches operating temperature. With the engine off and cool, check the coolant level again. Top up radiator and reservoir as neededair bubbles may work their way out as the bike heats and cools–this may require one or two checks after riding.
  • Monitor for leaks or sustained loss of coolant, which could indicate a loose clamp or another issue requiring attention.

2018 KLR650 Model-Specific Notes

  • The KLR650 uses a simple but effective cooling layout, but grit from off-road use can clog radiator fins: periodically inspect and gently clean the radiator exterior while servicing coolant.
  • Always use a coolant compatible with aluminum engine internals and avoid mixing types – this reduces corrosion risk and maximizes heat transfer.
  • The KLR650 has a coolant overflow tank behind the right lower panel. Be sure to check and refill this after every coolant change or flush.
  • If coolant level drops repeatedly after bleeding, inspect for leaks at hose clamps or consider a pressure test to check for head gasket issues (rare, but possible on higher-mileage bikes).

Disposal Tip

  • Never pour old coolant down the drain or into the ground. Take spent coolant to your local auto parts store or hazardous waste disposal facility.

Wrapping Up

Changing the coolant in your 2018 Kawasaki KLR650 boosts cooling performance and keeps your ride ready for any adventure. Regular service helps prevent overheating & prolongs engine life, especially on a bike known for traveling tough miles. As always, consult your owner's manual for official intervals and consider inspecting hoses & clamps while everything is apart for a comprehensive service.

Related Shopping Categories

Shop Radiators for a 2018 Kawasaki KLR650 Dirt Bike.

Shop Coolant for a 2018 Kawasaki KLR650 Dirt Bike.

Shop Temperature Sensors for a 2018 Kawasaki KLR650 Dirt Bike.

Shop Tools for a 2018 Kawasaki KLR650 Dirt Bike.

Shop Radiator Hoses for a 2018 Kawasaki KLR650 Dirt Bike.

Disclaimer: This guide is provided for general informational purposes only and is not intended to replace your motorcycle's official owner's manual. Always refer to your manufacturer's documentation for model-specific instructions, torque specifications, safety procedures, and maintenance requirements. If you are unsure or inexperienced, consider seeking assistance from a qualified mechanic or technician.