How to Change the Coolant in a 2009 Husqvarna WR300
Shop parts for a 2009 Husqvarna WR300 Dirt Bike.
Routine coolant changes are crucial for keeping your 2009 Husqvarna WR300 performing at its best, especially if you're pushing your two-stroke in technical trails or race settings. This guide from MotoSport is tailored to WR300 owners, so you know exactly what to expect for your machine.
What You Need
- Premium coolant compatible with high-performance two-stroke motorcycles
- Distilled water (if coolant is concentrate)
- 10mm or 12mm wrench (drain bolt size may vary)
- Phillips screwdriver (for radiator shrouds, if necessary)
- Drain pan
- Shop towels
- Funnel
- Gloves & protective eyewear
WR300-Specific Tips & Notes
- Coolant Capacity: The WR300's system holds less than 2 quarts. Never overfill to prevent excess pressure.
- Fluid Type: Always use a motorcycle-specific coolant made for aluminum radiators. Silicate-free, premium coolants like MAG Silkolene are highly recommended.
- Mixing: If using a concentrate, always mix with distilled water at 50/50 ratio. Never use tap water, as it will leave damaging deposits in the radiators.
- Tipping: The WR300's radiators can trap air bubbles. You'll need to gently tip the bike left & right during filling to fully burp the system for optimal cooling performance.
- No Additives: Do not use chemical additives in any WR300 lubricants or fluids–it can harm seals or engine components.
Step-by-Step Coolant Change Instructions
-
Let the bike cool.
Ensure the engine and radiator are completely cool to avoid burns. -
Remove the radiator cap.
Unscrew the cap to relieve any pressure and allow air in during draining. -
Place the drain pan under the water pump drain bolt.
The drain bolt is typically on the right side, near or on the water pump cover. -
Remove the drain bolt.
Allow coolant to drain fully. Clean the bolt and inspect the sealing washer for any damage and replace if needed. -
Flush if needed.
For maximum cleanliness, pour a small amount of distilled water through the radiator and let it drain. -
Reinstall the drain bolt.
Tighten to spec. Don't overtorque as the cases are aluminum. -
Slowly refill coolant.
Use a funnel to pour coolant into the radiator until it reaches the top of the filler neck. -
Burp the system.
Gently rock or tip the bike left and right 45 degrees several times. Squeeze radiator hoses and watch as air bubbles escape – the coolant level will drop. Continue topping off, burping the system until no more bubbles appear and level is stable. -
Start the engine briefly (radiator cap off).
Let it idle for 30–60 seconds, gently blipping the throttle. This circulates coolant and helps remaining air escape. Top up again if needed. -
Reinstall the radiator cap and check for leaks.
Wipe down all connections. Check for any leaks near the drain bolt or cap. -
Dispose of old coolant responsibly.
Never pour coolant down drains or on the ground–take it to a recycling center or auto parts store.
Why Change Coolant Regularly?
The WR300 is designed for aggressive riding, and fresh coolant ensures strong protection against overheating, corrosion, and internal scaling. Neglecting this service risks head gasket issues and power loss, especially in hot or slow, technical riding conditions unique to enduro two-strokes.
Additional WR300 Maintenance Insights
- Inspect radiator hoses and clamps during coolant changes–they can harden or crack over time.
- Radiator Fins: Keep them clean and straight for maximum airflow.
- Check water pump seals if you notice milky coolant, which can mean mixing with engine oil.
Changing coolant on your 2009 Husqvarna WR300 is simple preventative maintenance that pays off with reliability on the trail. Remember: take your time, fully burp the system, and stay on top of your enduro's care plan.
Related Shopping Categories
Shop Radiators for a 2009 Husqvarna WR300 Dirt Bike.
Shop Coolant for a 2009 Husqvarna WR300 Dirt Bike.
Shop Temperature Sensors for a 2009 Husqvarna WR300 Dirt Bike.
Shop Tools for a 2009 Husqvarna WR300 Dirt Bike.
Shop Radiator Hoses for a 2009 Husqvarna WR300 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.