How to Change the Coolant in a 2019 Suzuki RMZ450

Shop parts for a 2019 Suzuki RMZ450 Dirt Bike.

Regular coolant replacement on your 2019 Suzuki RMZ450 maximizes engine performance & longevity. This detailed guide from MotoSport shows how to perform the coolant change safely and correctly, with notes specific to your RMZ450.

Why Change Coolant?

Motorcycles like the RMZ450 do not have overflow tanks, meaning coolant levels can decrease under normal use. Old or degraded coolant reduces cooling efficiency & can lead to overheating and engine wear. Suzuki recommends checking the coolant level before every ride and replacing coolant periodically as part of routine maintenance.–3

Tools & Supplies Needed

  • Cool, clean workspace
  • Replacement coolant (Suzuki Super Long Life Coolant is recommended)
  • New drain bolt gasket/washer
  • Socket set (for drain bolt, usually 8mm or 10mm)
  • Funnel
  • Clean container for old coolant
  • Gloves & safety glasses
  • Rags

Step-by-Step Coolant Change

  1. Let the engine cool completely. Never open the radiator cap on a hot engine; wait until everything is cool to the touch to avoid scalding.
  2. Remove the radiator cap (top of left radiator) to allow the system to vent.
  3. Place your drain pan under the water pump area on the lower right side of the engine.
  4. Locate & remove the coolant drain bolt (at the base of the water pump cover). Allow all coolant to drain from the engine & radiator.
    Tip: Gently lean the bike side to side to help empty fluid from both radiators.
  5. Inspect and replace the drain bolt washer/gasket. Install a new washer to prevent leaks, and reinstall the drain bolt snugly.
  6. Add new coolant. Using a funnel, pour coolant into the radiator until it reaches the bottom of the filler neck.
    Note for RMZ450: If using Suzuki Super Long Life Coolant, use it straight – do not dilute. For traditional coolant, mix 50:50 with distilled water. Never use plain tap water.–3
  7. Bleed air from the system. Some RMZ450s feature an air bleeder bolt at the top of the cylinder head or radiator. Loosen the bleeder briefly while adding coolant to let trapped air escape, then retighten to 6 N-m (0.6 kgf-m, 4.5 lbf-ft).–3
  8. Reinstall the radiator cap. Ensure the cap locks firmly in place. A loose cap will cause coolant loss.
  9. Run & inspect. Start the engine, let it idle until it warms up, then shut down. Let it cool & recheck coolant level; add more as needed.
    Check for leaks at the drain bolt and around the cap.

Special RMZ450 Owner Tips

  • Always check coolant before every ride. The RMZ450's system doesn't have an overflow tank; coolant may drop slightly between services.–3
  • Use only motorcycle-specific coolant; avoid automotive coolant with silicates or minerals that can damage seals.
  • The system capacity is approximately 950 ml (1.0 US qt).–4
  • If riding in cold climates, verify your coolant offers protection for temperatures in your area.

Safe Disposal

Collect used coolant in a sealable container and drop it at an automotive recycling center. Never pour coolant on the ground or into drains – it is highly toxic.

When to Replace More Often

  • If you ride in mud, sand, or race frequently.
  • If you notice foaming, discoloration, or a drop in the coolant level beyond normal.
  • After repairs to the cooling system or following an engine overheat event.

For OEM and aftermarket cooling system parts, gaskets, and premium coolant for your 2019 Suzuki RMZ450, shop parts for a 2019 Suzuki RMZ450 Dirt Bike.

Related Shopping Categories

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Shop Temperature Sensors for a 2019 Suzuki RMZ450 Dirt Bike.

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Shop Radiator Hoses for a 2019 Suzuki RMZ450 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.