How to Change the Coolant in a 1988 Suzuki RM125: MotoSport Guide
Shop parts for a 1988 Suzuki RM125 Dirt Bike.
Changing the coolant in your 1988 Suzuki RM125 is a vital part of maintaining engine performance and preventing overheating on the track or trail. This step-by-step MotoSport guide is written for owners of the RM125 and covers all model-specific notes you need to keep your MMY running cool and reliable.
Why Change Your RM125 Coolant?
- Prevents overheating and potential engine damage.
- Flushes out contaminants and mineral deposits that build up over time.
- Ensures proper cooling efficiency, crucial for two-stroke engines like the RM125.
Tools and Supplies Needed
- Socket set (mainly 8mm – 10mm for drain bolt and hardware)
- Phillips screwdriver
- Container or drain pan for old coolant
- Distilled water for flushing
- Fresh coolant of recommended type
- Clean rag for cleanup
Step-by-Step Coolant Change Procedure
- Allow the engine to cool completely before beginning any work on the cooling system.
- Remove the seat and side panels if necessary to access the radiators and hoses comfortably.
- Locate the radiator cap (usually on top of the left radiator). Remove the cap to release pressure.
- Find the coolant drain bolt at the water pump (bottom right side of the engine). Place your drain pan underneath, then loosen and remove the drain bolt carefully to let the old coolant drain out completely.
- Once drained, pour distilled water into the radiator to flush out remaining old coolant and contaminants. Let the water drain out through the same port. Repeat until clear.
- Install and torque the drain bolt to factory specs. Check for any signs of wear or cross-threading on the bolt and replace if necessary.
- Refill radiator with fresh coolant up to the recommended level. Use a funnel to avoid spills.
- Replace the radiator cap securely, ensuring it's not bent or damaged.
- Start the bike and let it idle for a minute. Shut off, then check coolant level again, topping up as needed (air pockets may settle).
- Inspect for any leaks around the drain bolt and hoses after running the engine.
RM125 Model-Specific Notes
- The 1988 RM125 features a compact cooling system with twin radiators. Take extra care when opening bleed screws – if equipped – to avoid trapped air, which can compromise cooling performance.
- Use only premixed coolant formulated for aluminum radiators. Some aftermarket coolants protect better against corrosion inside lightweight RM radiators.
- Keep an eye on radiator fin condition – 1988 RM radiators are relatively exposed and may bend or clog with debris, affecting airflow and cooling.
- Replace old hoses if they feel brittle, as aging rubber is common on vintage models and can cause leaks under pressure.
Extra Tips for RM125 Owners
- Always dispose of old coolant at a local hazardous waste center – never pour it on the ground.
- Check and clean radiator guards regularly to maximize cooling system protection.
- Consider a coolant temperature gauge for extra insurance on hot riding days.
Keeping your 1988 Suzuki RM125 running cool means regular maintenance. These steps from MotoSport will help ensure your ride always stays ready to rip.
Related Shopping Categories
Shop Radiators for a 1988 Suzuki RM125 Dirt Bike.
Shop Coolant for a 1988 Suzuki RM125 Dirt Bike.
Shop Temperature Sensors for a 1988 Suzuki RM125 Dirt Bike.
Shop Tools for a 1988 Suzuki RM125 Dirt Bike.
Shop Radiator Hoses for a 1988 Suzuki RM125 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.