How to Change the Coolant in a 2018 Husqvarna FE350HQ: MotoSport Proprietary Guide

Shop parts for a 2018 Husqvarna FE350HQ Dirt Bike.

Routine coolant changes are essential for keeping your 2018 Husqvarna FE350HQ operating at peak performance and safeguarding its advanced engine. The FE350HQ features a high-compression single-cylinder engine — proper coolant maintenance is paramount to avoid overheating and maintain longevity. Here–s a step-by-step MotoSport-exclusive guide to help you change the coolant safely and efficiently.

What You–ll Need

  • Fresh quality motorcycle-specific coolant (avoid mixing types)
  • Socket wrench set (8mm and 10mm usually required)
  • Drain pan
  • Cotton shop rags
  • Funnel
  • Distilled water (for flushing)
  • Protective gloves & eyewear

Preparation Steps

  • Make sure the engine is cool before starting—never open the radiator cap on a hot motor.
  • Park the bike on a level surface or stand to ensure complete draining and safe access to all points.

Draining the Old Coolant

  • Remove the radiator cap to release any pressure and allow the system to drain freely.
  • Locate the coolant drain bolt (usually at the base of the water pump cover or on the lower side of the engine). Place your drain pan directly beneath this bolt.
  • Using the correct socket, carefully loosen and remove the drain bolt, letting all coolant drain out. Tip the bike slightly side-to-side if needed to clear all pockets of old fluid.
  • Check both radiators—the FE350HQ uses a split system, so patience ensures full drainage.
  • Inspect the drain bolt gasket and replace if damaged to prevent future leaks when reinstalling.

Optional: Flushing the Cooling System

  • Reinstall the drain bolt. Fill the system with distilled water via the radiator cap.
  • Briefly start the engine and let it idle for less than a minute with the cap off to circulate the water, then shut down and let it cool.
  • Drain the system again completely.

Refilling with New Coolant

  • Confirm the drain bolt is securely reinstalled.
  • Using a funnel, slowly fill the radiator with fresh coolant, pausing to let bubbles escape. Avoid overfilling.
  • Start the bike and let it idle with the radiator cap off—this allows trapped air to bleed out and the thermostat to open fully. If needed, top up the coolant as the level drops.
  • Once bubbling subsides and the level stabilizes, replace the radiator cap securely.

Final Steps & Checks

  • Wipe down any spilled coolant — glycol-based fluids are slippery and can damage surfaces.
  • Start the engine and bring it up to operating temperature. Check for leaks at the drain bolt and around the hoses.
  • After one ride, let the engine cool and recheck your coolant level, topping off if necessary.

2018 Husqvarna FE350HQ Owner Tips

  • The FE350HQ runs hot during technical riding. Consider a coolant recovery tank (reservoir) for enhanced cooling system protection and fewer boil-overs.
  • The radiator cap and plastics are uniquely Husqvarna. Always verify fitment before ordering replacement parts.
  • Monitor your fan operation—the FE350HQ–s electric fan engagement is crucial during summer or slow-speed rides. Faulty sensors or wiring will quickly lead to problems.
  • Never mix old and new coolant types—this can cause chemical incompatibility and compromised cooling performance.

Regular coolant changes are a simple way to protect your investment in your Husqvarna FE350HQ. If you need OE or upgrade parts, MotoSport has you covered every step of the way.

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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.