How to Change the Coolant in a 1980 Suzuki RM250
Shop parts for a 1980 Suzuki RM250 Dirt Bike.
Routine coolant changes are crucial to keeping your 1980 Suzuki RM250 running cool and preserving engine life on and off the track. This MotoSport.com-exclusive guide breaks down the coolant change process step by step, and highlights a few unique notes about this legendary two-stroke model.
What You'll Need
- Fresh coolant, suitable for aluminum radiators
- Drain pan
- 8 mm or 10 mm socket – verify by checking your drain bolt size
- Funnel
- Rags for cleanup
- Protective gloves and eye protection
- Torque wrench (recommended)
- New gasket washer for drain bolt (recommended)
Step-by-Step Coolant Change
- Ensure the engine is completely cool. Never open the radiator cap when the bike is hot—hot coolant can spray and cause burns.
- Remove the radiator cap. This relieves pressure and allows coolant to drain freely.
- Place a drain pan beneath the water pump area. On the RM250, the coolant drain bolt is typically found on or near the water pump cover (right engine case, lower side). Remove the drain bolt using your socket.
- Let old coolant fully drain. Tilting the bike gently to the right will help remove as much fluid as possible.
- Inspect & replace the drain bolt washer. A worn washer may cause leaks. Install a new one if available. Reinstall the drain bolt and gently torque it to 8.0 lb-ft (11 N·m) to avoid stripping the threads.
- Optional: Loosen the air bleeder bolt (if equipped, some models have one atop the cylinder or on the radiator). This helps prevent air pockets.
- Fill the radiator with fresh coolant using your funnel. Slowly pour until coolant reaches the base of the filler neck.
- Tighten the bleeder bolt (if you loosened it) as coolant seeps out. Reinstall the radiator cap.
- Start the engine and let it idle for 3-5 minutes. This circulates coolant and helps expel trapped air. Squeeze the upper radiator hose a few times to free any bubbles.
- Shut off the engine and let it cool fully. Double-check coolant level in the radiator, topping off if needed.
- Wipe away spills and clean any affected surfaces. Dispose of old coolant responsibly—it is toxic to humans and animals.
Tips for the 1980 Suzuki RM250 Owner
- Capacity: The cooling system takes approximately 950 ml (1.0 US quart). It's critical to avoid overfilling, which can cause overflow and poor cooling.
- Vintage Caution: Classic aluminum radiators and hoses on these bikes can be delicate. Always use a coolant designed for aluminum compatibility, and inspect hoses and clamps for signs of age or cracking before refilling.
- Bleeding Air: Any remaining air pockets can cause overheating. If you do not have a dedicated bleeder bolt, carefully loosen the highest radiator hose to let air escape as you fill with coolant, then retighten immediately once coolant flows steadily.
- Replacement Parts: If you find corroded or damaged radiator caps, hoses, or bolts, MotoSport.com carries a full selection of replacement parts to restore your cooling system's integrity.
MotoSport Pro Tip
The 1980 RM250 is famed for its strong mid-range power and classic suspension. Keeping the cooling system fresh is especially important if riding hard in sand, deep mud, or warm weather, as excessive heat can easily rob performance from an older high-strung two-stroke engine like this one.
Related Shopping Categories
Shop Radiators for a 1980 Suzuki RM250 Dirt Bike.
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Shop Temperature Sensors for a 1980 Suzuki RM250 Dirt Bike.
Shop Tools for a 1980 Suzuki RM250 Dirt Bike.
Shop Radiator Hoses for a 1980 Suzuki RM250 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.