How to Change the Coolant in a 2021 GAS GAS MC 65
Routine coolant changes are essential for keeping your 2021 GAS GAS MC 65's engine running cool and reliably. This guide explains the proprietary step-by-step process, plus key details specific to this model to help you ride with confidence.
What Makes the 2021 GAS GAS MC 65 Unique?
The MC 65 features a compact 2-stroke engine, aluminum radiator, and a lightweight chassis. Its closed cooling system can accumulate debris if you ride in mud, sand, or harsh conditions, so regular inspection and fresh coolant matter even more for kids and young racers.
Before You Begin
- Only work on your MC 65 when the engine is completely cold to prevent burns and pressure-related injuries.
- Secure the bike upright on a stand to ensure stability while you access the cooling system.
- Wear gloves and eye protection–coolant is toxic and can cause skin and eye irritation.
Tools & Supplies Needed
- Fresh coolant formulated for modern 2-stroke dirt bikes
- 8mm socket or wrench (to remove water pump drain bolt)
- Phillips/flathead screwdriver (for radiator cap and plastics, if needed)
- Catch pan for old coolant
- Funnel
Step-by-Step Coolant Change Process
- Remove the radiator cap: Locate the cap at the top of the left radiator. Twist to remove. This relieves pressure and allows coolant to drain smoothly.
- Place the drain pan: Position it under the water pump (lower right side of the engine case).
- Remove the drain bolt: Use an 8mm socket to undo the water pump cover bolt (check your owner's manual for the exact location). Let all coolant flow into the catch pan. Inspect the washer and replace it if damaged.
- Reinstall the drain bolt: Torque to the manufacturer specification (typically 10 Nm or about 7.4 lbf ft) with the washer in place.
- Fill with fresh coolant: Insert a funnel and carefully pour the new coolant into the radiator until the level is 10mm above the radiator fins. The MC 65 holds about 0.95 liters (1 quart).
- Bleed the cooling system: Some MC 65 models have a small bleeder screw on top of the cylinder head. Briefly loosen this as you fill to release any trapped air bubbles. Once coolant appears at the screw, retighten it.
- Reinstall the radiator cap.
- Check for leaks. Wipe off surfaces, then start the engine and let it idle for a few minutes. Shut off the engine, let it cool, and recheck coolant level–top off if needed.
Additional Owner Tips
- Inspect your radiator and hoses for mud, dents, or leaks during each coolant change. Clean or replace as needed to avoid overheating.
- For frequent sand or wet use: Clean radiator fins and check for blockage after every ride.
- Always dispose of used coolant responsibly–never pour it down the drain or onto the ground.
Regular coolant changes and radiator care are keys to maximizing your GAS GAS MC 65's longevity and performance on the track or trail.
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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.