Author Topic: Replacement of the brake pedal return spring  (Read 1863 times)

studioPaGoNa

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Replacement of the brake pedal return spring
« on: December 10, 2020, 09:10:16 »
Dear All,
I had a brake problem in summer. I learned that the brake pedal does not return to the up position and the brake seems to still drag or engage to some extent after depressing the pedal. I have to return the brake pedal by the toe of my foot. This phenomenon occur frequently in hot summer occasions but has gone in cooler autumn. While I am not sure of its cause, I decide to replace the rusty pedal return spring first of all. I tried several times to remove the spring, laying in the underpanel. I failed to remove the spring, which is very tough. No way for me. Therefore, may I have your advices of any better or easier methods as how to remove and replace the return spring?

Thank you in advance.
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kampala

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Re: Replacement of the brake pedal return spring
« Reply #1 on: December 11, 2020, 11:57:39 »
I don't know about a pedal not returning but when brakes drag and don't release many times (not always)  it's the rubber flex hoses that attach to the brake caliper.  After a number of years, the inside of the hoses swell -- when brakes are pressed and fluid is under pressure, the fluid pushes through these swollen hoses and activates the brakes, however when the pedal is released, the fluid is stuck in the caliper due to the swollen hoses and since it's under less pressure, cannot push it's way back.

If you search "swollen brake lines" even in google you will see images of hoses cut open to show the problem.   

« Last Edit: December 11, 2020, 12:04:40 by kampala »
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studioPaGoNa

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Re: Replacement of the brake pedal return spring
« Reply #2 on: December 11, 2020, 16:26:52 »
Oz san

Thank you for your input.
As I am afraid that the brake hoses were newly replaced two years ago,  I trust the brake hoses are fine.
Also I checked the eccentric bolt as if it is placed in the proper direction. While I presume that there are some faulties inside the brake booster, I try to replace the return spring at the first occasion.
If the situation remains unchanged even after replacement, I will dismantle the booster, which would be tough job.

Pagoda
'68 US Version, Moss Green Metallic with Cognac Leather, Automatic
'95 R32 GT-R White