Author Topic: Front brake caliper question  (Read 1489 times)

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Offline jjbunn

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Front brake caliper question
« on: Monday,January 19, 2015, 04:00:53 PM »


This is the driver's side front brake caliper, just removed from my '70 S2. I'm curious about the sheets that go between the brake pads and the pistons - what are they for? In any case, they are worn out - are they important?!

What's the best way of checking the pistons and operation of the caliper on the bench?

Many thanks!

Offline jbcollier

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Re: Front brake caliper question
« Reply #1 on: Monday,January 19, 2015, 04:48:26 PM »
They are an attempt to control brake "squeal".  You can toss 'em.

Offline BDA

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Re: Front brake caliper question
« Reply #2 on: Monday,January 19, 2015, 05:09:47 PM »
You can try pumping air in the caliper to test the function. Be sure to put a block of wood between the pistons first.

Offline jjbunn

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Re: Front brake caliper question
« Reply #3 on: Monday,January 19, 2015, 06:20:24 PM »
Great! I will toss them forthwith!

Thanks for the tip about pumping air to test the caliper.

Offline Grumblebuns

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Re: Front brake caliper question
« Reply #4 on: Tuesday,January 20, 2015, 08:17:56 AM »
If your calipers were anything like mine when I replace all of the seals, you may have one or two pistons refusing to come out. I got three of the four out with piston removal tools. The last one was a bitch refusing to come out even with compressed air pressure. I didn't have a grease gun to use hydraulic pressure using grease so I hooked the caliper up to my brake line and used cars brake system to push the last piston out. Obviously your MC has to be in working order and you have to replace the other piston in the caliper to restore the hydraulic seal   

Offline Runningwild

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Re: Front brake caliper question
« Reply #5 on: Tuesday,January 20, 2015, 09:33:36 AM »
We use those as shims in the race car brakes as the pads wear down so the caliper pistons don't extend out too far. I'd toss them.  Tom