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Old 06-11-2018, 10:27 AM   #1
Coach529
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Front Brake Woes......CPP Power Brakes Disc/ Disc

Last fall I started to notice some drag in the brakes after coming to a complete stop......nothing horrible but noticeable. Parked Henry and decided to investigate later.

Finally got around to it this weekend.

Put the front end up on jackstands and had my oldest boy stomp on the brakes and release them.....I could not move the the front tires for 5-6 seconds. Did this test for both sides.

Did the same on the back.....but those spun free immediately.



Any suggestions?

As always up against a deadline......huge car show this coming weekend!!

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Old 06-11-2018, 11:51 AM   #2
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Re: Front Brake Woes......CPP Power Brakes Disc/ Disc

I would remove the master cylinder and check the adjustment on the back side. Most often I have found the booster adjustment pushing on the master cylinder just a touch to much. Take a few turns off and test.
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Old 06-11-2018, 12:10 PM   #3
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Re: Front Brake Woes......CPP Power Brakes Disc/ Disc

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I would remove the master cylinder and check the adjustment on the back side. Most often I have found the booster adjustment pushing on the master cylinder just a touch to much. Take a few turns off and test.
Thanks, I will give that a shot.
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Old 06-11-2018, 12:22 PM   #4
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Re: Front Brake Woes......CPP Power Brakes Disc/ Disc

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Thanks, I will give that a shot.
I don't know why, but sometimes that little knob needs adjusted. Same thing happened on my 08, after 130K miles out of nowhere the brakes started dragging. Needed that nubber adjusted and all was good.
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Old 06-11-2018, 12:42 PM   #5
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Re: Front Brake Woes......CPP Power Brakes Disc/ Disc

Probably have about 1000 miles trouble free on build, until this came up.
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Old 06-12-2018, 12:12 AM   #6
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Re: Front Brake Woes......CPP Power Brakes Disc/ Disc

Dialed the adjuster in......no change.
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Old 06-12-2018, 06:43 AM   #7
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Re: Front Brake Woes......CPP Power Brakes Disc/ Disc

Most folks seem to approach these problems by taking semi-random stabs at it. Testing with a method usually leads to faster success.

I'd be checking for residual pressure. Apply and release the brakes then open a bleeder to see if the drag goes away. It's easier if you have a helper applying pressure to turn the wheel while you open the bleeder. If there's residual pressure the brakes would release very quickly. If I found pressure I would look at which port of the M/Cyl the front brakes are attached to. If they are attached to the rear port I would suspect pedal or pushrod adjustment. If the front brakes are on the forward port I would try to isolate the combination valve as the source of the problem by repeating the first test but opening the brake line at the master instead of opening a bleeder.

If the problem isn't caused by residual pressure I'd look at the caliper slides and pad guides to make sure they allow easy movement.
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Old 06-12-2018, 08:14 AM   #8
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Re: Front Brake Woes......CPP Power Brakes Disc/ Disc

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Dialed the adjuster in......no change.
Bummer, guess as mentioned. Start testing for pressure.
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Old 06-12-2018, 01:20 PM   #9
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Re: Front Brake Woes......CPP Power Brakes Disc/ Disc

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Originally Posted by 1project2many View Post
Most folks seem to approach these problems by taking semi-random stabs at it. Testing with a method usually leads to faster success.

I'd be checking for residual pressure. Apply and release the brakes then open a bleeder to see if the drag goes away. It's easier if you have a helper applying pressure to turn the wheel while you open the bleeder. If there's residual pressure the brakes would release very quickly. If I found pressure I would look at which port of the M/Cyl the front brakes are attached to. If they are attached to the rear port I would suspect pedal or pushrod adjustment. If the front brakes are on the forward port I would try to isolate the combination valve as the source of the problem by repeating the first test but opening the brake line at the master instead of opening a bleeder.

If the problem isn't caused by residual pressure I'd look at the caliper slides and pad guides to make sure they allow easy movement.
Thank you!!
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Old 06-12-2018, 09:38 PM   #10
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Re: Front Brake Woes......CPP Power Brakes Disc/ Disc

Pressure is being held by the Prop Valve.
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Old 06-12-2018, 11:26 PM   #11
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Re: Front Brake Woes......CPP Power Brakes Disc/ Disc

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Pressure is being held by the Prop Valve.
Good diagnosis, hope it going soon
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Old 06-12-2018, 11:47 PM   #12
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Re: Front Brake Woes......CPP Power Brakes Disc/ Disc

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Good diagnosis, hope it going soon
Prop Valve ordered from Amazon......should be here on Thursday!!
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Old 06-13-2018, 11:39 AM   #13
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Re: Front Brake Woes......CPP Power Brakes Disc/ Disc

Good job. And the valve is easy to reach so it should be a quick fix.
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Old 06-16-2018, 12:34 AM   #14
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Re: Front Brake Woes......CPP Power Brakes Disc/ Disc

Prop valve replaced......problem solved!!
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Old 06-16-2018, 12:09 PM   #15
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Re: Front Brake Woes......CPP Power Brakes Disc/ Disc

MiraclePieCo had trouble with his CPP prop valve too. Allegedly there was a “bad batch”
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Old 06-16-2018, 08:37 PM   #16
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Re: Front Brake Woes......CPP Power Brakes Disc/ Disc

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MiraclePieCo had trouble with his CPP prop valve too. Allegedly there was a “bad batch”
I had issues when I originally installed this system. The original Prop Valve leaked and was replaced under warranty.
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Old 06-17-2018, 08:56 AM   #17
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Re: Front Brake Woes......CPP Power Brakes Disc/ Disc

We love the idea of going "all new" with parts, but I have learned that a used OEM part is sometimes better than a new aftermarket version. Maybe prop valves are going to end up in that category?
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Old 06-17-2018, 07:55 PM   #18
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Re: Front Brake Woes......CPP Power Brakes Disc/ Disc

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MiraclePieCo had trouble with his CPP prop valve too. Allegedly there was a “bad batch”
Great! Hope mine works when I get everything going. Been sitting for 3 months and I have not completed it yet.
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