How to Change the Coolant in a 1987 Honda CR500
Shop parts for a 1987 Honda CR500 Dirt Bike.
The 1987 Honda CR500 is legendary for its raw power, air-cooled simplicity, and robust performance on the track – but keeping the cooling system healthy is crucial for longevity and optimal operation. Proper coolant changes prevent overheating and corrosion within the aluminum radiators and engine. Here—s a step-by-step process tailored exclusively for CR500 owners:
What You Need
- Ethylene Glycol-based coolant (safe for aluminum radiators)
- Fresh water pump crush washer (Honda part number 90463-ML7-000)
- Socket set & hand tools
- Catch pan for old coolant
- Rags for cleanup
Preparation
- Work with the engine completely cool to avoid burns from hot coolant or steam.
- Place the bike on a stand for easier access to all components.
- Remove the radiator shrouds or tank if necessary for better access to the radiator cap and hoses.
Drain the Old Coolant
- Place the catch pan under the water pump area.
- Remove the radiator cap to relieve internal pressure and allow draining.
- Locate the coolant drain bolt at the base of the water pump (right side of the engine) and remove it, along with the crush washer.
- Let the old coolant fully drain from the system. Slightly tilting the bike from side-to-side can help evacuate trapped coolant.
- Once drained, replace the crush washer and re-install the drain bolt securely.
Flush the System (Recommended for Dirty or Old Coolant)
- Fill the radiator with distilled water.
- Reinstall the radiator cap, start the engine, and let it idle for a few minutes to circulate.
- Shut off the engine, let it cool, and drain the water as before.
- Repeat if the drained water is still cloudy or discolored, then proceed to final fill.
Refill with New Coolant
- Slowly pour fresh ethylene glycol coolant into the radiator, filling it up to the bottom of the filler neck.
- If your CR500 has an external overflow reservoir, fill to the indicated line.
- Lightly shake or rock the bike to burp out air bubbles and top off the coolant as the level drops.
Bleed the System & Final Checks
- Reinstall the radiator cap.
- Start the engine and let it idle until thoroughly warmed up to operating temperature—watching for leaks at the drain bolt or hoses.
- After cooling back down, remove the radiator cap and check the coolant level; add more if necessary.
- Reinstall any tank or shrouds removed for the procedure.
Honda CR500 Model Tips & Notes
- The 1987 CR500 uses an aluminum radiator system that requires ethylene glycol-based coolant for corrosion protection.
- Always replace the crush washer at the drain bolt—a reusable washer risks leaks under pressure or vibration.
- Routine coolant service (every two years or after heavy race use) is recommended due to the CR500–s high-output two-stroke engine, which can generate significant heat.
- If you see persistent air bubbles after riding, it’s likely harmless aeration; however, ongoing rapid coolant loss may indicate a deeper issue like water pump seal failure.
Maintaining the cooling system is vital for the big-bore CR500. Stay ahead of major repairs — keep your coolant fresh, and your ride will keep delivering that legendary power all season.
Related Shopping Categories
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Shop Radiator Hoses for a 1987 Honda CR500 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.