Brake and Clutch Pedal Adjustment - Height and Free Play

01
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Finding Your Proper Pedal Free Play

Check your pedal free play by hand.
Use your fingers to find pedal free play. photo by Tegger

Most pedals (brake and clutch) should have a small amount of free play. Free play is the distance the pedal can be pressed before it makes contact on the other end. In other words, when you place your foot on the pedal lightly, it doesn't move at all, but when you put the weight of your foot on it, there's a certain amount of distance that it will go down before you can feel that it has started to activate the braking (or clutch) system. The amount of acceptable free play is usually very small, as in less than 10mm small (that's a centimeter).​​

What You'll Need:

  • ruler
  • open end wrenches
  • line wrenches
  • pliers
  • Wite-Out, nail polish or another way to mark a metal surface

To test your pedal free play, it's best to use your fingers. Move the pedal up and down and you'll be able to feel the looseness. You may be able to tell by hand when the free play is right. To be mathematical about it, all you need is a ruler. Place one end of the ruler against the floor and the other alongside the pedal. Lift the pedal to the top of its range and note the measurement. Now push the pedal just far enough for it to make contact on the other side (the end of the free play) and note this measurement. The "contact point" at the end of the free play is the point where the pedal actually starts to activate the braking system. You'll feel it start to exert pressure on the system at this point, compared to the floppy up and down movement you'll get in the area of the pedal known as free play. Subtract measurement two from measurement one and this is your free play amount.

02
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Adjusting the Pedal Height and Free Play

Don't rotate the push rod too early.
Loosen the lock nuts then rotate the push rod to adjust. Photo by Tegger

Now that you know which way you need to go with your adjustment, you're ready to fine-tune the pedal height and free play. Follow the pedal upward to the point it attaches to a rod, called the push rod. Before you touch anything with your tools, it's a good idea to mark the pushrod with your Wite-Out. You just need a dot on the part that's facing down toward you. This dot will let you be sure you don't rotate the pushrod until you want to. Any rotation ahead of time will throw off your measurements. 

Now locate the locking nuts for the push rod. In the application pictured below (a Honda) there is a 12-point star nut and a hex nut which keep the rod from drifting out of adjustment on its own. Here's where your line wrenches come into play. Slip a line wrench over each of the lock nuts and loosen by turning them in opposite directions. Don't let the push rod rotate yet (if it does rotate a little, use your mark to bring it back). Any rotation will cause the free play to change, and you're not ready quite.

With the lock nuts loosened, you can rotate the push rod. As it rotates, the pedal free play will increase or decrease slowly. You may need pliers to grip the push rod tight enough to rotate it.

When you have the pedal free play adjusted, tighten the lock nuts and drive around the block. Retest the pedal height to be sure.

Special thanks to Tegger!