2004 Mazda 3 L4-2.3LFACTORY OEM SERVICE PROCEDURE

Coolant: Service and Repair

ENGINE COOLANT REPLACEMENT

Warning:
- Remove and install all parts when the engine is cold, otherwise they can cause severe burns or serious injury.
- Turn off the engine and wait until it is cool. Even then, be very careful when removing the cap. Wrap a thick cloth around it and slowly turn it counterclockwise 2.5 turns. Step back while the pressure escapes.
- When you are sure all the pressure is gone, turn the cap using the cloth, and remove it.


Caution:
- Use engine coolant at a concentration that meets the environmental conditions in which the vehicle is driven, otherwise engine damage could occur.
- The engine has aluminum parts that can be damaged by alcohol or methanol antifreeze. Do not use alcohol or methanol in the cooling system. Use only ethylene-glycol-based coolant.
- Use only soft (demineralized) water in the coolant mixture. Water that contains minerals will reduce the coolant's effectiveness.
- Engine coolant damages paint. If engine coolant does get on a painted surface, rinse it off quickly.

Factory service manual diagram




1. Remove the cooling system cap.
2. Remove the under cover.

Factory service manual diagram




3. Remove the radiator drain plug and drain the engine coolant into a container.
4. Flush the cooling system with water until all traces of color are gone.
5. Let the system drain completely.
6. Tighten the radiator drain plug.
Tightening torque 1.2 - 1.5 Nm (13 - 15 kgf-cm, 11 - 13 inch lbs.)
7. Referring to the chart, select proper volume percentage of the water and coolant.

Factory service manual diagram




Antifreeze solution mixture percentage

8. Refill the coolant into the coolant reserve tank up to the MAX mark on the tank.
9. Fully install the cooling system cap.

Caution: If the water temperature gauge rises too high, stop the engine and decrease the water temperature to prevent overheating. Then, verify the malfunctioning part and repair or replace it.

10. Start the engine and idle it until the thermometer indicator is in the center when the engine is below 1,500 rpm.
11. Bleed the air by following the procedures below. At this time, be careful of the. coolant temperature to prevent overheating.
1 Run the engine at 2,500 rpm for 5 min.
2 Run the engine at 3,000 rpm for 5 s, then idle.
3 Repeat Step (1), (2) twice.
12. Stop the engine, and inspect the coolant level after the coolant temperature decreases (water temperature gauge indicates 'C' or less).
13. Check the coolant level.
- If It is low, refill the coolant into the coolant reserve tank up to the MAX mark on the tank.
14. Inspect for coolant leakage.
- If the coolant leaks, specify the malfunctioning part and repair or replace it.
Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.

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