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How brakes work?


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G'day,

Well I give up! Can anyone point me to a detailed description on how the auto-adjuster park-brake activates the front discs on my '90 Series L 4WD?

 

I have completely dismantled a caliper, but still don't understand how the slack is taken up by the multistart thread when both the inner actuator (male thread) and piston (female thread) are prevented from rotating! One or the other surely has to rotate. What am I missing here?

 

(This all started when one piston would not screw screw back in).

 

Thanks,

DG

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i don't believe it is auto adjusting. There are adjusting nuts on the crossbar that holds the cables up at the handle to take up the slack. if you had auto adjusters there wouldn't be the need for that.

 

Yes, they do auto adjust for pad wear. That's why you have to screw the pistons back into the caliper. The adjuster nuts for the cables are just for rough adjustment and balance between cables. The mechanisms inside the calipers are the fine adjustment for pad wear. Unfortunately, I'm not real clear on the specifics of how they work.

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G'day,

Well I give up! Can anyone point me to a detailed description on how the auto-adjuster park-brake activates the front discs on my '90 Series L 4WD?

 

I have completely dismantled a caliper, but still don't understand how the slack is taken up by the multistart thread when both the inner actuator (male thread) and piston (female thread) are prevented from rotating! One or the other surely has to rotate. What am I missing here?

 

(This all started when one piston would not screw screw back in).

 

Thanks,

DG

The pistons on the front calipers have a ratcheting screw mechanism built in to them. If the ratchet doesn't work the front brakes will not self adjust and your brake pedal will not feel right.

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