How to Change the Coolant on a 2020 KTM 350 EXC-F: Step-by-Step Guide

Shop parts for a 2020 KTM 350 EXC-F Dirt Bike.

Changing the coolant on your 2020 KTM 350 EXC-F is recommended maintenance to ensure proper engine cooling and long-term engine health. Follow this unique MotoSport guide for the right approach, plus model-specific tips every 350 EXC-F owner should know.

What You Need

  • Phillips or flat-blade screwdriver (to remove shrouds if necessary)
  • 8mm socket or wrench (for drain bolt)
  • Catching container/pan
  • New coolant (choose a high-quality ready-mix for aluminum engines – avoid mixing with old types or water unless flushing)
  • Clean funnel
  • Torque wrench (recommended)
  • Shop rags
  • Protective gloves

Preparation and Safety

  • Only perform a coolant change with the engine completely cool.
  • Position the bike upright on a stand for best access to the radiators and drain locations.
  • Work in a well-ventilated area and ensure pets or children are not nearby; coolant is toxic.

Step-by-Step Coolant Replacement

  1. Remove seat and, if needed, the radiator shrouds for clear access to the radiator cap.
  2. Take off the radiator cap: Slowly turn the cap counterclockwise to relieve any pressure before fully removing.
  3. Locate the coolant drain bolt. On the 350 EXC-F, this is typically the lower bolt on the water pump cover (usually 8mm). Position your drain pan beneath it.
  4. Remove the drain bolt and allow all coolant to fully drain.
    • Tilt the bike slightly if needed to encourage a complete drain.
    • Inspect the old coolant for contamination or debris – cloudy or rusty coolant is a sign of overdue maintenance.
  5. Reinstall the drain bolt with a new washer if available and torque to manufacturer spec to prevent leaks.
  6. Flush if needed: If old coolant is cloudy, refill with distilled water, run the engine briefly (do not let it overheat), drain, and repeat until the drained water runs clear.
  7. Fill with fresh coolant: Use a clean funnel and slowly pour in new coolant until at the base of the radiator filler neck.
  8. Check for air pockets: With the cap off, gently rock the bike side to side and massage the upper radiator hose to help purge trapped air.
  9. Bleed the cooling system: KTM recommends elevating the front wheel by about 19 inches when filling to help air escape through the system, especially if using the bleed screws on the cylinder head. Tighten the bleed screw(s) when only coolant (no bubbles) flows from them.
  10. Reinstall radiator cap once you're confident all air is out.
  11. Start the engine, let it idle till warmed up, then shut off and let the bike fully cool.
    • Recheck the coolant level at both radiator and, if equipped, expansion/overflow tank. Add as necessary.
  12. Inspect for leaks around the drain bolt, water pump, and radiator area. Replace any suspect seals or O-rings.

Special Notes for the KTM 350 EXC-F Model

  • The EXC-F's compact head and split radiator design makes full bleeding important – neglecting trapped air can result in overheating or inconsistent coolant levels.
  • Factory coolant is often orange but always match your coolant type (silicate-free, for aluminum engines). Avoid mixing types to prevent gelling or corrosion.
  • If your KTM has an auxiliary radiator fan, verify it cycles on during warm-up after the change. A working fan is critical if you trail ride at low speeds.
  • Check coolant level before every ride during your next few outings. The first few heat cycles may displace remaining air; top up if needed.

When to Change Your KTM's Coolant

  • At least once per year or every 2,000 miles, whichever comes first
  • After a season of heavy use, especially in hot or muddy riding
  • If coolant appears discolored or contaminated

Proper coolant maintenance keeps your KTM 350 EXC-F's high-compression engine protected – letting you ride hard and worry-free, season after season.

Related Shopping Categories

Shop Radiators for a 2020 KTM 350 EXC-F Dirt Bike.

Shop Coolant for a 2020 KTM 350 EXC-F Dirt Bike.

Shop Temperature Sensors for a 2020 KTM 350 EXC-F Dirt Bike.

Shop Tools for a 2020 KTM 350 EXC-F Dirt Bike.

Shop Radiator Hoses for a 2020 KTM 350 EXC-F 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.