Brake bleeding difficulties, left front |
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Brake bleeding difficulties, left front |
EJP914 |
Jun 12 2021, 09:44 PM
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#1
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Member Group: Members Posts: 260 Joined: 14-June 03 From: Monroeville, PA Member No.: 821 |
I am bleeding the brakes on my 73 1.7 with a Motive power bleeder after replacing the calipers, rotors, hard and soft lines at each wheel. The rears and right front bled out great. No air bubbles and continuous flow of fluid. Problem is on the left front.
When I pressurize the brake system via the bleeder tank and open the bleed screw I do get a small amount of bubbles in the catch jar. While the system is under pressure (about 10 lbs) and bleeder screw closed, the brake pedal is at the top and very firm the way it should be. Once I release the pressure in the tank, the brake rotor spins free. That little bit of contact you typically get with the pads is gone. Brake pedal has also lost its firm feeling. The right front wheel has that little bit of drag from the pads. I have checked all over and nothing seems to be leaking. If there was leak somewhere, I don't think the bleeder tank would hold at 10 lbs. Any ideas on why this is happening? Bad caliper? Would very much appreciate the help. EJP914 |
willieg |
Jun 12 2021, 10:55 PM
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#2
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Member Group: Members Posts: 132 Joined: 13-August 18 From: Pleasant Hill Member No.: 22,389 Region Association: Northern California |
I bought a rebuilt caliper once from one of the cheapo places and had the same issues. I split the caliper apart and found one of the passages through the caliper was blocked with debris. Cleaned out the blockage, reassembled the caliper and it worked
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EJP914 |
Jun 13 2021, 08:59 AM
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#3
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Member Group: Members Posts: 260 Joined: 14-June 03 From: Monroeville, PA Member No.: 821 |
Thanks Willieq.
Any other thoughts out there before I remove the caliper??? Thanks |
mepstein |
Jun 13 2021, 10:33 AM
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#4
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914-6 GT in waiting Group: Members Posts: 19,313 Joined: 19-September 09 From: Landenberg, PA/Wilmington, DE Member No.: 10,825 Region Association: MidAtlantic Region |
Make sure the soft lines are new or newer.
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cary |
Jun 13 2021, 11:25 AM
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#5
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Advanced Member Group: Members Posts: 3,900 Joined: 26-January 04 From: Sherwood Oregon Member No.: 1,608 Region Association: Pacific Northwest |
New brakes I leave over night at 20#'s to test for leaks.
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EJP914 |
Jun 14 2021, 06:21 AM
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#6
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Member Group: Members Posts: 260 Joined: 14-June 03 From: Monroeville, PA Member No.: 821 |
Soft lines at the wheels are new.
Have had system at 15 lbs for multiple hours and no leaks found. Will do again as suggested |
bdstone914 |
Jun 14 2021, 06:38 AM
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#7
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bdstone914 Group: Members Posts: 4,536 Joined: 8-November 03 From: Riverside CA Member No.: 1,319 |
@EJP914
Sure sounds like an internal caliper blockage. You may get lucky by removing the hard line and retracting the pistons and flush out the blockage. If not it sounds like you need to split the caliper. |
infraredcalvin |
Jun 14 2021, 07:44 AM
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#8
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Distracted Member Group: Members Posts: 1,528 Joined: 25-August 08 From: Ladera Ranch, CA Member No.: 9,463 Region Association: Southern California |
Agreed, just had a similar issue, I had a hanging caliper on my car, It would not bleed. I removed both bleed nipples, found they were both clogged. Cleared them, rebled system, now everything works as it should. Turns out caliper was only partially full of fluid.
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EJP914 |
Jun 14 2021, 09:03 AM
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#9
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Member Group: Members Posts: 260 Joined: 14-June 03 From: Monroeville, PA Member No.: 821 |
Many thanks guys. Caliper is under warranty. Supplier is ordering me a replacement. Hope that cures the problem. Driving me nuts
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bdstone914 |
Jun 14 2021, 09:11 AM
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#10
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bdstone914 Group: Members Posts: 4,536 Joined: 8-November 03 From: Riverside CA Member No.: 1,319 |
Many thanks guys. Caliper is under warranty. Supplier is ordering me a replacement. Hope that cures the problem. Driving me nuts You may want check the replacement before installing. Place a wood block bewteen tbe caliper halves about the thickness of the rotor. The pistons should move with about 50 lbs of air pressure. |
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