Mazda6 is another winner in the Mazda line. Yes, this is something you owners know well enough, but it sure fun to repeat it. Working on the clutch and adjusting it yourself is one of those things that you can do in an afternoon. Your Mazda6 will thank you when you're done.
Check the reservoir that holds the clutch fluid in your Mazda6. If it's low, fill it to the recommended level. Pump the pedal a few times to restore the pressure. This could be all the adjustment you need.
Measure the height of your pedal and free play in the clutch pedal. Write this down so you can return the pedal to these measurements should you make a mistake. You can also measure at which point the clutch engages for the same reason (in case you make a mistake).
Engage the parking brake, and set wheel chocks behind the wheels so they won't move. Start the Mazda6, and utilize a FFT as a clutch stop. Attempt to shift into reverse. If you are able to do so smoothly, add another FFT until it begins to resist. This is the engagement point of the clutch. Measure the height of the piled FFT's and record that number. That number represents the height of the "engage point."
Alter the clutch engagement point if it is not in the recommended specs. In the European manual, it is recommended that the engagement point of the Mazda6 be 20 mm, which is less than 1 inch.
Remove the FFT's, then loosen the "locking nut," which is located on the master cylinder pushrod of the Mazda6, by using a 12mm wrench. Re-tighten the nut after you have made the adjustment.
Adjust the clutch pedal of the Mazda6 by loosening the bolt at the top of the clutch pedal with a 1/2 inch wrench. Move the pedal up or down until you achieve 1 mm to 3 mm of free play.
Measure the clutch pedal height to see whether your adjustment is good. Test drive the vehicle, then adjust the clutch further, or keep it as is.