How to Change the Coolant in a 2019 Sherco 300SE-R

Shop parts for a 2019 Sherco 300SE-R Dirt Bike.

Maintaining the cooling system is one of the most essential routine services for your 2019 Sherco 300SE-R. Timely coolant changes protect the engine from overheating, corrosion, and premature wear–critical for both performance and longevity on and off the trail. Follow this MotoSport-exclusive step-by-step guide to safely change your coolant and ensure optimal function of your Sherco 2-stroke.

What You&ll Need

  • Manufacturer-approved coolant (do not use plain water or non-approved fluids)
  • Drain pan or suitable container for used coolant
  • Socket set (including 8mm and 10mm)
  • New crush washers or gaskets (for bleed screw and drain bolt, if needed)
  • Funnel
  • Shop towels
  • Protective gloves

Important Model-Specific Notes

  • The 2019 Sherco 300SE-R cooling system holds around 1.1 liters of fluid .
  • Always use coolants compatible with aluminum radiators and magnesium engine parts–Sherco recommends a universal D 4 -25°C rated antifreeze .
  • Never substitute water or non-motorcycle specific coolant, as this can cause engine corrosion and failure .
  • Ensure the bike is on a stable, level surface; it should be vertical during draining and filling to measure accurately .

Step-by-Step Coolant Change Procedure

  1. Allow Engine to Cool:
    Make sure your bike is completely cool to prevent burns or injury from hot coolant under pressure.
  2. Access Radiator and Reservoir:
    Remove the seat and shrouds as necessary for access. Locate the radiator cap and overflow container.
  3. Drain Old Coolant:
    • Place a drain pan under the engine.
    • Remove the radiator cap to relieve any pressure.
    • Locate the coolant drain screw (typically at the base of the water pump) and remove it .
    • Allow coolant to drain fully. Open the bleed screw located on the left radiator to ensure complete drainage .
    • If equipped, drain the overflow/expansion tank as well.
  4. Inspect Components:
    • Check hoses for brittleness or cracks, ensure all clamps are tight, and the radiator fins are undamaged .
    • Replace worn parts as needed for best performance.
  5. Reinstall Drain Screw:
    • After the coolant has drained, replace the drain screw using a new gasket, tightening to the manufacturer torque spec (typically 6Nm) .
    • Retighten the bleed screw if it was removed.
  6. Refill with Fresh Coolant:
    • Fill slowly through the radiator cap opening while the bleed screw is loose to let air escape .
    • Once coolant starts to seep from the bleed screw without bubbles, tighten the bleed screw with a new washer (torque to 8Nm if applicable) .
    • Continue filling until fluid reaches the FULL level, generally around 1.1L for this model .
    • Check the overflow/expansion tank; it should also be filled to the indicated level.
  7. Recheck and Bleed System:
    • With the bike vertical, briefly start the engine with the radiator cap off and monitor for air bubbles. Top off if fluid drops.
    • Reinstall the radiator cap, ensuring a secure seal.
    • Check for leaks at all hoses, clamps, and screws.
  8. Dispose of Old Coolant Properly:
    • Always take used coolant to an approved collection center. Do not pour down the drain or on the ground .

Technical Tips for the 2019 Sherco 300SE-R

  • Inspect the water pump seal periodically–leaks from the weep hole signal seal failure and require water pump service .
  • If you notice coolant loss or overheating, check not only the radiator and hoses but also the thermostat and cap for wear or malfunction.
  • Careful coolant changes extend the life of your engine, reduce risk of corrosion, and help maintain optimum power delivery, especially in demanding trail or race conditions.

Properly maintaining your Sherco's vital systems gives you the performance advantage and durability you count on. If you need OEM or aftermarket parts to complete your maintenance, MotoSport has you covered.

Related Shopping Categories

Shop Radiators for a 2019 Sherco 300SE-R Dirt Bike.

Shop Coolant for a 2019 Sherco 300SE-R Dirt Bike.

Shop Temperature Sensors for a 2019 Sherco 300SE-R Dirt Bike.

Shop Tools for a 2019 Sherco 300SE-R Dirt Bike.

Shop Radiator Hoses for a 2019 Sherco 300SE-R 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.