Brake failure

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Steve S
Posts: 107
Joined: Tue Sep 20, 2005 2:56 pm

Re: Brake Failure

Post by Steve S » Tue Feb 07, 2017 12:25 am

It takes very little air to cause massive brake fade. When you bleed the brakes, each pump yields a lot of fluid with a small amount of bubbles. However the brakes go from soft to firm. If you somehow had enough air coming in from below to displace 3/4" of fluid in the cylinder and overflow it, you'd probably completely empty all four cylinders and half of the hard lines! - Steve Simmons, TC8975 On 2/6/2017 11:49 PM, 'Norman Verona' norman@frenchblat.com [mg-tabc] wrote:
Steve,

In which case the fluid would be overflowing from the master.

[b]Norman Verona[/b]

La Foie, 49520, Noellet, France

Tel: 0033 (0)2 41 92 73 44

Mob: 0033 (0)7 70 70 23 79

Website: www FrenchBlat com (put dots in the spaces)

[b]From:[/b] mg-tabc@yahoogroups.com [mg-tabc@yahoogroups.com] [b]On Behalf Of [/b]Steve S mail@mgnuts.com [mg-tabc] [b]Sent:[/b] 07 February 2017 02:48 [b]To:[/b] MG tabcgroups MG-tabc@yahoogroups.com [b]Subject:[/b] Re: [mg-tabc] Brake Failure

Agreed. Air can definitely come in past the wheel cylinder cups. No leak necessary. If the master cylinder returns faster than the brake shoes, air can be pulled in. Ensure the brake springs are all in correct working condition to prevent it from happening. - Steve Simmons, TC8975

On 2/6/2017 5:26 PM, Stephen D Stierman morgan7709@sbcglobal.net [mg-tabc] wrote:

I had a continual problems with air entering the braking system, likely coming via wheel cylinder(s) that may have been seeping slightly, don't discard that end of the system as the problem. Bleeding would result in a hard peddle that over time would become softer in use.

Steve TC2911

[b]From:[/b] "James Davis burburyclose@yahoo.com [mg-tabc]" mg-tabc-noreply@yahoogroups.com [b]To:[/b] Mg-Tabc mg-tabc@yahoogroups.com [b]Sent:[/b] Monday, February 6, 2017 5:02 PM [b]Subject:[/b] [mg-tabc] Brake Failure

Thanks to all of you for your ideas. I checked the brake lines,MC, etc with no indication of leakage. Then I bled the line out. Much air in there. The brakes came back after bleeding. Perhaps when I tested the brakes HARD the day before, I explosed some intermittent crack etc in the system which only shows up with hard use. I plan to give it a rigorous test after my diff comes back from being worked over. I'm on pins and needles driving it now and will try to break the fault during the next hard test. I'll keep the group informed. Thanks again. Jim Davis TC 7225 Houston


Duncan
Posts: 95
Joined: Sat Jul 18, 2015 12:04 pm

Re: Brake Failure

Post by Duncan » Tue Feb 07, 2017 1:17 am

Might have never been properly bled when brakes last serviced. And remember that H2O contains oxygen, and H20 will get into the TC system's fluid, and it does not require a chemistry lab or textbook perfect boiling of the brake fluid to liberate some of oxygen from the water. It just happens, from pressure and other things.. Another good reason to flush your system every couple years and put in fresh brake fluid. It is good to be constantly paranoid about potential brake problems in these cars, as the brake system is not all that great from a modern safety standpoint. The TC parking brake, on the other hand, is superb. Duncan- CA To: "Mg-Tabc" mg-tabc@yahoogroups.com> Date: Monday, February 6, 2017, 2:02 PM .--------------------------------------------
On Mon, 2/6/17, James Davis burburyclose@yahoo.com [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote: Subject: [mg-tabc] Brake Failure Thanks to all of you for your ideas. I checked the brake lines,MC, etc with no indication of leakage. Then I bled the line out. Much air in there. The brakes came back after bleeding. Perhaps when I tested the brakes HARD the day before, I explosed some intermittent crack etc in the system which only shows up with hard use. I plan to give it a rigorous test after my diff comes back from being worked over. I'm on pins and needles driving it now and will try to break the fault during the next hard test. I'll keep the group informed. Thanks again. Jim Davis TC 7225 Houston

Norman Verona
Posts: 107
Joined: Sun May 17, 2015 4:21 am

Re: Brake Failure

Post by Norman Verona » Tue Feb 07, 2017 1:25 am

Steve, the point is the OP said there was no signs of a leak. To get total brake failure the master cylinder must empty completely. And to get sudden total failure the leak must be substantial. I have suggested that before going for the unusual, with the master cylinder the wheel cylinders and the brake pipes are inspected. It would appear we are talking a substantial leak so it should be clearly visible.

 

[b]Norman Verona[/b]

La Foie, 49520, Noellet, France

Tel: 0033 (0)2 41 92 73 44

Mob: 0033 (0)7 70 70 23 79

Website: www FrenchBlat com (put dots in the spaces)

 

[b]From:[/b] mg-tabc@yahoogroups.com [mailto:mg-tabc@yahoogroups.com] [b]On Behalf Of [/b]Steve S mail@mgnuts.com [mg-tabc] [b]Sent:[/b] 07 February 2017 09:25 [b]To:[/b] 'MG tabcgroups' MG-tabc@yahoogroups.com> [b]Subject:[/b] Re: [mg-tabc] Brake Failure

 

 

It takes very little air to cause massive brake fade.  When you bleed the brakes, each pump yields a lot of fluid with a small amount of bubbles.  However the brakes go from soft to firm.  If you somehow had enough air coming in from below to displace 3/4" of fluid in the cylinder and overflow it, you'd probably completely empty all four cylinders and half of the hard lines! - Steve Simmons, TC8975  

On 2/6/2017 11:49 PM, 'Norman Verona' norman@frenchblat.com [mg-tabc] wrote:

 

Steve,

 

In which case the fluid would be overflowing from the master.

 

[b]Norman Verona[/b]

La Foie, 49520, Noellet, France

Tel: 0033 (0)2 41 92 73 44

Mob: 0033 (0)7 70 70 23 79

Website: www FrenchBlat com (put dots in the spaces)

 

[b]From:[/b] mg-tabc@yahoogroups.com [mg-tabc@yahoogroups.com] [b]On Behalf Of [/b]Steve S mail@mgnuts.com [mg-tabc] [b]Sent:[/b] 07 February 2017 02:48 [b]To:[/b] MG tabcgroups MG-tabc@yahoogroups.com [b]Subject:[/b] Re: [mg-tabc] Brake Failure

 

 

Agreed.  Air can definitely come in past the wheel cylinder cups.  No leak necessary.  If the master cylinder returns faster than the brake shoes, air can be pulled in.  Ensure the brake springs are all in correct working condition to prevent it from happening. - Steve Simmons, TC8975 

On 2/6/2017 5:26 PM, Stephen D Stierman morgan7709@sbcglobal.net [mg-tabc] wrote:

 

I had a continual problems with air entering the braking system, likely coming via wheel cylinder(s) that may have been seeping slightly, don't discard that end of the system as the problem.  Bleeding would result in a hard peddle that over time would become softer in use.

Steve TC2911

 

[b]From:[/b] "James Davis burburyclose@yahoo.com [mg-tabc]" mg-tabc-noreply@yahoogroups.com [b]To:[/b] Mg-Tabc mg-tabc@yahoogroups.com [b]Sent:[/b] Monday, February 6, 2017 5:02 PM [b]Subject:[/b] [mg-tabc] Brake Failure

 

 

Thanks to all of you for your ideas. I checked the brake lines,MC, etc with no indication of leakage. Then I bled the line out. Much air in there. The brakes came back after bleeding. Perhaps when I tested the brakes HARD the day before, I explosed some intermittent crack etc in the system which only shows up with hard use. I plan to give it a rigorous test after my diff comes back from being worked over. I'm on pins and needles driving it now and will try to break the fault during the next hard test. I'll keep the group informed. Thanks again. Jim Davis TC 7225 Houston

 

 

 


Norman Verona
Posts: 107
Joined: Sun May 17, 2015 4:21 am

Re: Brake Failure

Post by Norman Verona » Tue Feb 07, 2017 2:28 am

Duncan,

 

The problem, as reported, was the brakes were working fine and next day the pedal went to the floor. I would guess they were bled OK. Air and water ingress into the system happens very slowly over a long period of time, not overnight.

 

 

 

 

[b]Norman Verona[/b]

La Foie, 49520, Noellet, France

Tel: 0033 (0)2 41 92 73 44

Mob: 0033 (0)7 70 70 23 79

Website: www FrenchBlat com (put dots in the spaces)

 

[b]From:[/b] mg-tabc@yahoogroups.com [mailto:mg-tabc@yahoogroups.com] [b]On Behalf Of [/b]Duncan morelists@yahoo.com [mg-tabc] [b]Sent:[/b] 07 February 2017 10:14 [b]To:[/b] mg-tabc@yahoogroups.com; burburyclose@yahoo.com [b]Subject:[/b] Re: [mg-tabc] Brake Failure

 

 

Might have never been properly bled when brakes last serviced. And remember that H2O contains oxygen, and H20 will get into the TC system's fluid, and it does not require a chemistry lab or textbook perfect boiling of the brake fluid to liberate some of oxygen from the water. It just happens, from pressure and other things.. Another good reason to flush your system every couple years and put in fresh brake fluid. It is good to be constantly paranoid about potential brake problems in these cars, as the brake system is not all that great from a modern safety standpoint. The TC parking brake, on the other hand, is superb. Duncan- CA To: "Mg-Tabc" mg-tabc@yahoogroups.com> Date: Monday, February 6, 2017, 2:02 PM .--------------------------------------------
On Mon, 2/6/17, James Davis burburyclose@yahoo.com [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote: Subject: [mg-tabc] Brake Failure   Thanks to all of you for your ideas. I checked the brake lines,MC, etc with no indication of leakage. Then I bled the line out. Much air in there. The brakes came back after bleeding. Perhaps when I tested the brakes HARD the day before, I explosed some intermittent crack etc in the system which only shows up with hard use. I plan to give it a rigorous test after my diff comes back from being worked over. I'm on pins and needles driving it now and will try to break the fault during the next hard test. I'll keep the group informed. Thanks again. Jim Davis TC 7225 Houston


Stephen D Stierman
Posts: 63
Joined: Fri Dec 26, 2003 5:04 am

Re: Brake Failure

Post by Stephen D Stierman » Tue Feb 07, 2017 3:19 am

Not so Norman,As Steve points out and I have found personally, enough air entering via wheel cylinder(s) and a bit of loss at the same place, will cause a peddle to become softer over time, eventually causing brake actuation to become almost nil.Steve TC2911 From: "'Norman Verona' norman@frenchblat.com [mg-tabc]" mg-tabc-noreply@yahoogroups.com> [b]To:[/b] 'Steve S' mail@mgnuts.com>; 'MG tabcgroups' MG-tabc@yahoogroups.com> [b]Sent:[/b] Tuesday, February 7, 2017 4:25 AM [b]Subject:[/b] RE: [mg-tabc] Brake Failure   Steve, the point is the OP said there was no signs of a leak. To get total brake failure the master cylinder must empty completely. And to get sudden total failure the leak must be substantial. I have suggested that before going for the unusual, with the master cylinder the wheel cylinders and the brake pipes are inspected. It would appear we are talking a substantial leak so it should be clearly visible.  Norman VeronaLa Foie, 49520, Noellet, FranceTel: 0033 (0)2 41 92 73 44Mob: 0033 (0)7 70 70 23 79Website: www FrenchBlat com (put dots in the spaces)  [b]From:[/b] mg-tabc@yahoogroups.com [mailto:mg-tabc@yahoogroups.com] [b]On Behalf Of [/b]Steve S mail@mgnuts.com [mg-tabc] [b]Sent:[/b] 07 February 2017 09:25 [b]To:[/b] 'MG tabcgroups' MG-tabc@yahoogroups.com> [b]Subject:[/b] Re: [mg-tabc] Brake Failure    It takes very little air to cause massive brake fade.  When you bleed the brakes, each pump yields a lot of fluid with a small amount of bubbles.  However the brakes go from soft to firm.  If you somehow had enough air coming in from below to displace 3/4" of fluid in the cylinder and overflow it, you'd probably completely empty all four cylinders and half of the hard lines!- Steve Simmons, TC8975  On 2/6/2017 11:49 PM, 'Norman Verona' norman@frenchblat.com [mg-tabc] wrote:
  Steve, In which case the fluid would be overflowing from the master. Norman VeronaLa Foie, 49520, Noellet, FranceTel: 0033 (0)2 41 92 73 44Mob: 0033 (0)7 70 70 23 79Website: www FrenchBlat com (put dots in the spaces) [b]From:[/b] mg-tabc@yahoogroups.com [mg-tabc@yahoogroups.com] [b]On Behalf Of [/b]Steve S mail@mgnuts.com [mg-tabc] [b]Sent:[/b] 07 February 2017 02:48 [b]To:[/b] MG tabcgroups MG-tabc@yahoogroups.com [b]Subject:[/b] Re: [mg-tabc] Brake Failure   Agreed.  Air can definitely come in past the wheel cylinder cups.  No leak necessary.  If the master cylinder returns faster than the brake shoes, air can be pulled in.  Ensure the brake springs are all in correct working condition to prevent it from happening.- Steve Simmons, TC8975 On 2/6/2017 5:26 PM, Stephen D Stierman morgan7709@sbcglobal.net [mg-tabc] wrote:  I had a continual problems with air entering the braking system, likely comi! ng via wheel cylinder(s) that may have been seeping slightly, don't discard that end of the system as the problem.  Bleeding would result in a hard peddle that over time would become softer in use.Steve TC2911 [b]From:[/b] "James Davis burburyclose@yahoo.com [mg-tabc]" mg-tabc-noreply@yahoogroups.com [b]To:[/b] Mg-Tabc mg-tabc@yahoogroups.com [b]Sent:[/b] Monday, February 6, 2017 5:02 PM [b]Subject:[/b] [mg-tabc] Brake Failure   Thanks to all of you for your ideas. I checked the brake lines,MC, etc with no indication of leakage. Then I bled the line out. Much air in there. The brakes came back after bleeding. Perhaps when I tested the brakes HARD the day before, I explosed some intermittent crack etc in the system which only shows up with hard use. I plan to give it a rigorous test after my diff comes back from being worked over. I'm on pins and needles driving it now and will try to break the fault during the next hard test. I'll keep the group informed. Thanks again. Jim Davis TC 7225 Houston 
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Bruce Doran-Veevers
Posts: 22
Joined: Mon Jan 01, 2001 6:43 am

Re: Brake Failure

Post by Bruce Doran-Veevers » Tue Feb 07, 2017 3:42 am

I had this same problem , there was an air bulb in the right rear line ,

 

[b]From:[/b] mg-tabc@yahoogroups.com [mailto:mg-tabc@yahoogroups.com] [b]On Behalf Of [/b]'Norman Verona' norman@frenchblat.com [mg-tabc] [b]Sent:[/b] Tuesday, February 7, 2017 5:29 AM [b]To:[/b] 'Duncan' morelists@yahoo.com>; mg-tabc@yahoogroups.com; burburyclose@yahoo.com [b]Subject:[/b] RE: [mg-tabc] Brake Failure

 

 

Duncan,

 

The problem, as reported, was the brakes were working fine and next day the pedal went to the floor. I would guess they were bled OK. Air and water ingress into the system happens very slowly over a long period of time, not overnight.

 

 

 

 

[b]Norman Verona[/b]

La Foie, 49520, Noellet, France

Tel: 0033 (0)2 41 92 73 44

Mob: 0033 (0)7 70 70 23 79

Website: www FrenchBlat com (put dots in the spaces)

 

[b]From:[/b] mg-tabc@yahoogroups.com [mg-tabc@yahoogroups.com] [b]On Behalf Of [/b]Duncan morelists@yahoo.com [mg-tabc] [b]Sent:[/b] 07 February 2017 10:14 [b]To:[/b] mg-tabc@yahoogroups.com; burburyclose@yahoo.com [b]Subject:[/b] Re: [mg-tabc] Brake Failure

 

 

Might have never been properly bled when brakes last serviced. And remember that H2O contains oxygen, and H20 will get into the TC system's fluid, and it does not require a chemistry lab or textbook perfect boiling of the brake fluid to liberate some of oxygen from the water. It just happens, from pressure and other things.. Another good reason to flush your system every couple years and put in fresh brake fluid. It is good to be constantly paranoid about potential brake problems in these cars, as the brake system is not all that great from a modern safety standpoint. The TC parking brake, on the other hand, is superb. Duncan- CA To: "Mg-Tabc" mg-tabc@yahoogroups.com> Date: Monday, February 6, 2017, 2:02 PM .--------------------------------------------
On Mon, 2/6/17, James Davis burburyclose@yahoo.com [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote: Subject: [mg-tabc] Brake Failure   Thanks to all of you for your ideas. I checked the brake lines,MC, etc with no indication of leakage. Then I bled the line out. Much air in there. The brakes came back after bleeding. Perhaps when I tested the brakes HARD the day before, I explosed some intermittent crack etc in the system which only shows up with hard use. I plan to give it a rigorous test after my diff comes back from being worked over. I'm on pins and needles driving it now and will try to break the fault during the next hard test. I'll keep the group informed. Thanks again. Jim Davis TC 7225 Houston


Clive P Sherriff
Posts: 11
Joined: Sat Feb 20, 2016 12:22 am

Re: Brake Failure

Post by Clive P Sherriff » Tue Feb 07, 2017 5:18 am

Steve,   Also don't use too strong a return spring or the pedal (and so master cylinder seal ) will snap back faster than fluid can be replaced, and suck in air past the seal.   Clive   = ===============================  
----- Original Message ----- [b]From:[/b] mail@mgnuts.com [mg-tabc] [b]To:[/b] MG-tabc@yahoogroups.com [b]Sent:[/b] Tuesday, February 07, 2017 1:48 AM [b]Subject:[/b] Re: [mg-tabc] Brake Failure   Agreed.  Air can definitely come in past the wheel cylinder cups.  No leak necessary.  If the master cylinder returns faster than the brake shoes, air can be pulled in.  Ensure the brake springs are all in correct working condition to prevent it from happening. - Steve Simmons, TC8975 On 2/6/2017 5:26 PM, Stephen D Stierman morgan7709@sbcglobal.net [mg-tabc] wrote:   I had a continual problems with air entering the braking system, likely coming via wheel cylinder(s) that may have been seeping slightly, don't discard that end of the system as the problem.  Bleeding would result in a hard peddle that over time would become softer in use. Steve TC2911 [b]From:[/b] "James Davis burburyclose@yahoo.com [mg-tabc]" mg-tabc-noreply@yahoogroups.com [b]To:[/b] Mg-Tabc mg-tabc@yahoogroups.com [b]Sent:[/b] Monday, February 6, 2017 5:02 PM [b]Subject:[/b] [mg-tabc] Brake Failure   Thanks to all of you for your ideas. I checked the brake lines,MC, etc with no indication of leakage. Then I bled the line out. Much air in there. The brakes came back after bleeding. Perhaps when I tested the brakes HARD the day before, I explosed some intermittent crack etc in the system which only shows up with hard use. I plan to give it a rigorous test after my diff comes back from being worked over. I'm on pins and needles driving it now and will try to break the fault during the next hard test. I'll keep the group informed. Thanks again. Jim Davis TC 7225 Houston
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Clive P Sherriff
Posts: 11
Joined: Sat Feb 20, 2016 12:22 am

Re: Brake Failure

Post by Clive P Sherriff » Tue Feb 07, 2017 5:25 am

Hi Norman,   Yes, I Disagree, it takes very little air in the master cylinder seal space, say about 1to 2cc (compared with the comparitively huge volume of the reservoir) to completely foul things up.    Additional sucked in air would perhaps go back in the reservoir, but then just bubble to the surface and out of the vent hole.  You would see no difference in the reservoir level at all without very detailed measutement.  Even a couple cc of air would lift the level less than 1mm when spread accross the large reservoir fluid surface area.   Clive = ========================================
----- Original Message ----- [b]From:[/b] norman@frenchblat.com [b]To:[/b] csherriff99@gmail.com ; burburyclose@yahoo.com ; mg-tabc@yahoogroups.com [b]Sent:[/b] Tuesday, February 07, 2017 7:44 AM [b]Subject:[/b] RE: [mg-tabc] Brake Failure Clive, in which case the fluid would be coming out of the top of the master. All I m saying is that if a system is full of fluid to get air in some fluid must come out. Do you disagree with this?

 

[b]Norman Verona[/b]

La Foie, 49520, Noellet, France

Tel: 0033 (0)2 41 92 73 44

Mob: 0033 (0)7 70 70 23 79

Website: www FrenchBlat com (put dots in the spaces)

 

[b]From:[/b] Clive P Sherriff [mailto:csherriff99@gmail.com] [b]Sent:[/b] 08 February 2017 00:46 [b]To:[/b] Norman Verona norman@frenchblat.com>; 'James Davis' burburyclose@yahoo.com>; 'Mg-Tabc' mg-tabc@yahoogroups.com> [b]Subject:[/b] Re: [mg-tabc] Brake Failure

 

Norman, If as I suggested at the start, there is a problem with the master cylinder seals, then it's quite possible that air has been sucked into the master cylinder by the pedal strokes.

 

Clive

m mmmmmmmmmmmmmmm

 

 

----- Original Message -----

[b]From:[/b] norman@frenchblat.com%20[mg-tabc]

[b]To:[/b] burburyclose@yahoo.com ; mg-tabc@yahoogroups.com

[b]Sent:[/b] Monday, February 06, 2017 10:42 PM

[b]Subject:[/b] RE: [mg-tabc] Brake Failure

 

 

Jim,

Something wrong with your statement. If there is air in the system then the fluid that was in there must have leaked out.  I suspect you do have a leak otherwise the air cannot get into the system.

Think of a bottle which is full of water. To get more water in, or air, then the water in the bottle must overflow.

[b]Norman Verona[/b]

La Foie, 49520, Noellet, France

Tel: 0033 (0)2 41 92 73 44

Mob: 0033 (0)7 70 70 23 79

Website: www FrenchBlat com (put dots in the spaces)

[b]From:[/b] mg-tabc@yahoogroups.com [mg-tabc@yahoogroups.com] [b]On Behalf Of [/b]James Davis burburyclose@yahoo.com [mg-tabc] [b]Sent:[/b] 06 February 2017 23:03 [b]To:[/b] Mg-Tabc mg-tabc@yahoogroups.com> [b]Subject:[/b] [mg-tabc] Brake Failure

 

Thanks to all of you for your ideas. I checked the brake lines,MC, etc with no indication of leakage. Then I bled the line out. Much air in there. The brakes came back after bleeding. Perhaps when I tested the brakes HARD the day before, I explosed some intermittent crack etc in the system which only shows up with hard use. I plan to give it a rigorous test after my diff comes back from being worked over. I'm on pins and needles driving it now and will try to break the fault during the next hard test. I'll keep the group informed. Thanks again. Jim Davis TC 7225 Houston

 

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Clive P Sherriff
Posts: 11
Joined: Sat Feb 20, 2016 12:22 am

Re: Brake Failure

Post by Clive P Sherriff » Tue Feb 07, 2017 5:34 am

Duncan,   No, physics and chemistry don't work that way, in anyone's Lab.   Water in the system does reduce braking, but only because the water is more compressible than brake fluid.   You could probably get quite reasonable braking by draining all the fluid and replacing it with water, or kerosine, or malt whisky, about any liquid in fact.   Anyway, even boiling does not release oxygen from water, it produces water gas (steam).     Could be fun though, because if it did and produced  oxygen, it would also have to produce hydrogen    Then the brake system may well explode !   Clive = =================================    
----- Original Message ----- [b]From:[/b] morelists@yahoo.com [mg-tabc] [b]To:[/b] mg-tabc@yahoogroups.com ; burburyclose@yahoo.com [b]Sent:[/b] Tuesday, February 07, 2017 9:14 AM [b]Subject:[/b] Re: [mg-tabc] Brake Failure   Might have never been properly bled when brakes last serviced. And remember that H2O contains oxygen, and H20 will get into the TC system's fluid, and it does not require a chemistry lab or textbook perfect boiling of the brake fluid to liberate some of oxygen from the water. It just happens, from pressure and other things.. Another good reason to flush your system every couple years and put in fresh brake fluid. It is good to be constantly paranoid about potential brake problems in these cars, as the brake system is not all that great from a modern safety standpoint. The TC parking brake, on the other hand, is superb. Duncan- CA To: "Mg-Tabc" mg-tabc@yahoogroups.com> Date: Monday, February 6, 2017, 2:02 PM .-------------------------------------------- On Mon, 2/6/17, James Davis burburyclose@yahoo.com [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote: Subject: [mg-tabc] Brake Failure   Thanks to all of you for your ideas. I checked the brake lines,MC, etc with no indication of leakage. Then I bled the line out. Much air in there. The brakes came back after bleeding. Perhaps when I tested the brakes HARD the day before, I explosed some intermittent crack etc in the system which only shows up with hard use. I plan to give it a rigorous test after my diff comes back from being worked over. I'm on pins and needles driving it now and will try to break the fault during the next hard test. I'll keep the group informed. Thanks again. Jim Davis TC 7225 Houston [img]https://ec.yimg.com/ec?url=http%3A%2F%2Fstatic.avast.com%2Femails%2Favast-mail-stamp.png&t=1522511313&sig=KuTH4iwEXQcDOUYZ9uUhbA--~D[/img] This email has been checked for viruses by Avast antivirus software. www.avast.com


John Kallend
Posts: 17
Joined: Sun Mar 17, 2013 7:50 am

Re: Brake Failure

Post by John Kallend » Tue Feb 07, 2017 5:46 am

How do you know it was full to begin with? _____________________________John KallendProfessor EmeritusDepartment of Mechanical, Materials and Aerospace EngineeringDepartment of PhysicsIIT, Chicago
On Tue, Feb 7, 2017 at 1:44 AM, 'Norman Verona' norman@frenchblat.com [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote: [u][/u] Clive, in which case the fluid would be coming out of the top of the master. All I m saying is that if a system is full of fluid to get air in some fluid must come out. Do you disagree with this?[u][/u][u][/u]

[u][/u] [u][/u]

[b]Norman Verona[u][/u][u][/u][/b]

La Foie, 49520, Noellet, France[u][/u][u][/u]

Tel: 0033 (0)2 41 92 73 44[u][/u][u][/u]

Mob: 0033 (0)7 70 70 23 79[u][/u][u][/u]

Website: www FrenchBlat com (put dots in the spaces)[u][/u][u][/u]

[u][/u] [u][/u]

[b]From:[/b] Clive P Sherriff [mailto:csherriff99@gmail.com] [b]Sent:[/b] 08 February 2017 00:46 [b]To:[/b] Norman Verona norman@frenchblat.com>; 'James Davis' burburyclose@yahoo.com>; 'Mg-Tabc' mg-tabc@yahoogroups.com> [b]Subject:[/b] Re: [mg-tabc] Brake Failure[u][/u][u][/u]

[u][/u] [u][/u]

Norman, If as I suggested at the start, there is a problem with the master cylinder seals, then it's quite possible that air has been sucked into the master cylinder by the pedal strokes.[u][/u][u][/u]

[u][/u][u][/u]

Clive[u][/u][u][/u]

m mmmmmmmmmmmmmmm[u][/u][u][/u]

[u][/u][u][/u]

[u][/u][u][/u]

----- Original Message ----- [u][/u][u][/u]

[b]From:[/b] norman@frenchblat.com%20[mg-tabc] [u][/u][u][/u]

[b]To:[/b] burburyclose@yahoo.com ; mg-tabc@yahoogroups.com [u][/u][u][/u]

[b]Sent:[/b] Monday, February 06, 2017 10:42 PM[u][/u][u][/u]

[b]Subject:[/b] RE: [mg-tabc] Brake Failure[u][/u][u][/u]

[u][/u] [u][/u]

[u][/u][u][/u]

Jim, [u][/u][u][/u]

Something wrong with your statement. If there is air in the system then the fluid that was in there must have leaked out. I suspect you do have a leak otherwise the air cannot get into the system.[u][/u][u][/u]

Think of a bottle which is full of water. To get more water in, or air, then the water in the bottle must overflow.[u][/u][u][/u]

[b]Norman Verona[/b][u][/u][u][/u]

La Foie, 49520, Noellet, France[u][/u][u][/u]

Tel: 0033 (0)2 41 92 73 44[u][/u][u][/u]

Mob: 0033 (0)7 70 70 23 79[u][/u][u][/u]

Website: www FrenchBlat com (put dots in the spaces)[u][/u][u][/u]

[b]From:[/b] mg-tabc@yahoogroups.com [mg-tabc@yahoogroups.com] [b]On Behalf Of [/b]James Davis burburyclose@yahoo.com [mg-tabc] [b]Sent:[/b] 06 February 2017 23:03 [b]To:[/b] Mg-Tabc mg-tabc@yahoogroups.com> [b]Subject:[/b] [mg-tabc] Brake Failure[u][/u][u][/u]

[u][/u][u][/u]

Thanks to all of you for your ideas. I checked the brake lines,MC, etc with no indication of leakage. Then I bled the line out. Much air in there. The brakes came back after bleeding. Perhaps when I tested the brakes HARD the day before, I explosed some intermittent crack etc in the system which only shows up with hard use. I plan to give it a rigorous test after my diff comes back from being worked over. I'm on pins and needles driving it now and will try to break the fault during the next hard test. I'll keep the group informed. Thanks again. Jim Davis TC 7225 Houston[u][/u][u][/u][u][/u][u][/u]

[u][/u] [u][/u]

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This email has been checked for viruses by Avast antivirus software. www.avast.com [u][/u][u][/u][u][/u] [u][/u]


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