 Brake Failure, Brake Failure |
|
|
|
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG.
This site is not affiliated with Porsche in any way. Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners. |
|
|
| Rod911964 |
 Dec 1 2023, 01:47 PM
Post
#1
|
|
Newbie  Group: Members Posts: 12 Joined: 21-December 19 From: Buffalo Member No.: 23,752 Region Association: None  |
914 Brake failure!
Took my 914 1.8 on a 2300 mile rally this past autumn. 914 did great except the brakes went spongy. So I bled the brakes thinking the was air in the lines. Actually bled them 3x. On the way home I had to pump the brakes to get any braking action, ugh! Got home and put the 914 on the lift and started the diagnostic process. Upon the 1st round of inspections… no leaks, reservoir maintains fluid level, no indication of caliper hang up. Took the master cylinder off and disassembled, scoped the bores and found annular rust in the bores. So I figure I’m getting fluid bypass to not hold fluid pressure. Probably the root cause. Then I take the pads out to measure both the rotors and pads to spec. All looks good except for the front left pads. Uneven/slanted wear! (See pics). If I hold the friction surfaces parallel it would mean pistons are cocked. Doesn’t make sense. Or the rotor surface is not parallel. So what causes this situation? Thanks in advance. Rob Attached thumbnail(s) 
|
   |
 
|
  |
Replies
| ChrisFoley |
Dec 16 2023, 06:42 AM
Post
#2
|
|
I am Tangerine Racing Group: Members Posts: 7,990 Joined: 29-January 03 From: Bolton, CT Member No.: 209 Region Association: None 
|
A low pedal is typical after a caliper rebuild. The new seals often grip the pistons a little too tightly and won't allow self adjustment until a few hundred miles of operation.
|
|
|
|
Posts in this topic
Rod911964 Brake Failure Dec 1 2023, 01:47 PM
Rod911964 RE: Brake Failure Dec 1 2023, 01:50 PM mepstein I don’t know the problem but the rotors have par... Dec 1 2023, 05:40 PM mskala Are the 'piston retaining plates', those 2... Dec 1 2023, 07:02 PM technicalninja I see wear like that all of the time!
Jammed s... Dec 1 2023, 09:04 PM porschetub Pistons won't tip over with pads that thick or... Dec 1 2023, 11:07 PM mlindner I'm with porschetub, wheel bearing bad or not ... Dec 2 2023, 08:39 AM Rod911964 update to my original question/concern.
I talked ... Dec 15 2023, 01:40 PM infraredcalvin Yup, looks like simple piston clocking is needed. ... Dec 15 2023, 11:27 PM Dave_Darling A couple of things to try to get a hard pedal near... Dec 16 2023, 01:06 AM
mgp4591
A low pedal is typical after a caliper rebuild. T... Dec 16 2023, 10:17 PM |
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:
|
Lo-Fi Version | Time is now: 2nd July 2025 - 11:12 PM |
Invision Power Board
v9.1.4 © 2025 IPS, Inc.