How to Change the Coolant in a 2025 GAS GAS EX 250
Keeping your 2025 GAS GAS EX 250 engine at optimal temperature is essential for performance and longevity. Coolant not only manages heat–it prevents internal corrosion and protects key components. Here is a robust, proprietary MotoSport guide to changing the coolant on your GAS GAS EX 250, along with important notes specific to this popular MMY dirt bike.
Preparation
- Allow the engine to cool completely before starting to prevent burns.
- Place the bike vertically on a stand for full fluid drainage.
- Have the following on hand: correct type of coolant (consult your owner's manual, silicate-free motorcycle coolant is generally recommended), a drain pan, a small funnel, and basic tools (including an 8 mm or 10 mm wrench for the drain bolt and a Phillips screwdriver for the radiator cap).
Step-by-Step Coolant Change
-
Remove the Radiator Cap
Open the radiator cap slowly to release any pressure. The cap is usually located at the highest point of the left radiator. Always remove the cap with the engine cold. -
Locate and Remove the Coolant Drain Bolt
Find the coolant drain bolt at the lowest point of the water pump cover on the right-hand engine case. Place the drain pan beneath and remove the bolt. Allow all coolant to drain. -
Flush (Recommended but Optional)
If you notice residue, scale, or old coolant build-up, you can flush the system with distilled water. Fill the system with distilled water, briefly start the bike, then shut it off, drain again, and repeat until drainage runs clear. -
Inspect Sealing Areas
Wipe the drain bolt threads and sealing washers. Inspect the inside of the radiator cap and filler neck for any white or "sugary" deposits–this can indicate past coolant issues. Clean if necessary. Replace the sealing washer if damaged. -
Reinstall the Drain Bolt
Thread in the drain bolt by hand to avoid cross-threading, then torque it to factory spec (as listed in your owner's manual or torque chart). -
Add New Coolant
Using a funnel, add coolant to the radiator until it reaches the filler neck. On the EX 250, there is a small bleeder screw or port on top of the cylinder head. Loosen this while filling until air bubbles stop escaping and only coolant runs out, then tighten the bleeder. This ensures no air pockets in the system. -
Check for Leaks
Visually confirm no coolant is seeping from the drain bolt or hoses. -
Start & Bleed the System
Start the engine with the radiator cap off and let it idle for a minute. Gently rock the bike side to side, watching for bubbles as any remaining air escapes. Top off coolant if the level drops, then securely reinstall the radiator cap. -
Refill the Overflow Reservoir (if equipped)
Check and fill the auxiliary coolant reservoir to its specified line, if your EX 250 has one. -
Dispose of Old Coolant Responsibly
Used coolant is toxic to humans, animals, and the environment. Bring it to a certified recycling center or hazardous waste facility.
Model-Specific Notes for the 2025 GAS GAS EX 250
- The 2025 EX 250 uses a high-capacity, closed-loop cooling system similar to KTM and Husqvarna sibling models–be thorough with bleeding the system to prevent air pockets, which can lead to overheating.
- The bleeder port on the cylinder head is crucial for ensuring air is completely expelled from the system. Always loosen it briefly during the refill process and again after running the engine and topping off.
- Use only motorcycle-specific coolant–avoid automotive coolants which can damage seals or trigger corrosion due to incompatible additives.
- If your location experiences freezing temperatures, always confirm your coolant provides adequate antifreeze properties for year-round protection.
After-Service Checklist
- Check coolant level again after the bike's next ride–top off if necessary.
- Visually inspect the drain bolt and hoses for leaks.
- Monitor the temperature gauge and be alert for any indication of overheating.
With these steps, your 2025 GAS GAS EX 250 will stay cool and ready for the next ride. Need parts or more maintenance supplies? Shop parts for your ride now!
Related Shopping Categories
Shop Radiator Hoses for Your Ride
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.