Classic Audi Technical Mech/Tech Suspension & Brakes » C3 Brakes seizing -help!

Reply
 
Thread Tools Display Modes
Old 05-05-18, 06:36 PM   #1
Ringmaster
Grown up member
Classic Audi Club Member
 
Ringmaster's Avatar
 
Join Date: Apr 2008
Posts: 951
Default C3 Brakes seizing -help!

Hi folks!

Thought I'd take my C3 out for a spin in this lovely weather, as it hadn't been out for a couple of weeks.

I began to notice that it felt like something was holding it back. Then the brake pedal felt much firmer that I am used to. Just before I got home something seemed to go thud under the car somewhere, and all seemed back to normal.

The front discs were steaming hot. Rear discs were very hot too, but nothing like the front.
I don't think the problem has gone away.

Can both front calipers seize at the same time? They are original.

Any ideas please.....
Ringmaster is offline   Reply With Quote
Old 05-05-18, 06:53 PM   #2
Duffy3074
Senior Member
Classic Audi Club Member
 
Join Date: Aug 2015
Location: Dalgety Bay, Fife
Posts: 1,455
Default

No way all seize at the same time, the rears especially do little work compared to the fronts.

My guess would be a sticky master cylinder or brake linkage.

You really would need to take it off to have a look at it, I’m assuming there’s no ABS or warning lights on the dash
Duffy3074 is offline   Reply With Quote
Old 05-05-18, 07:15 PM   #3
John.
4 ring whore!
Classic Audi Club Member
 
John.'s Avatar
 
Join Date: Mar 2011
Location: Scottish Borders.
Posts: 6,470
Default

As above I would think.....seized linkage or sticking master cylinder.
Does it have a vacuum servo or is it boosted via the PS pump?
John. is offline   Reply With Quote
Old 05-05-18, 08:33 PM   #4
Ringmaster
Grown up member
Classic Audi Club Member
 
Ringmaster's Avatar
 
Join Date: Apr 2008
Posts: 951
Default

No ABS.

Boosted by PAS pump.

What is the brake linkage?

Last edited by Ringmaster; 05-05-18 at 08:35 PM.
Ringmaster is offline   Reply With Quote
Old 06-05-18, 06:02 AM   #5
John.
4 ring whore!
Classic Audi Club Member
 
John.'s Avatar
 
Join Date: Mar 2011
Location: Scottish Borders.
Posts: 6,470
Default

Quote:
Originally Posted by Ringmaster View Post
What is the brake linkage?
The mechanics between the pedal rubber and the master cylinder.

I had same problem on my coupe, I replaced the master cylinder to cure it.
John. is offline   Reply With Quote
Old 06-05-18, 06:26 PM   #6
Ringmaster
Grown up member
Classic Audi Club Member
 
Ringmaster's Avatar
 
Join Date: Apr 2008
Posts: 951
Default

Thanks chaps.....

From what you say it sounds like the master cylinder.

Wouldn't be unexpected for a 31 year old part I suppose......

Ringmaster is offline   Reply With Quote
Old 26-05-18, 05:55 PM   #7
Ringmaster
Grown up member
Classic Audi Club Member
 
Ringmaster's Avatar
 
Join Date: Apr 2008
Posts: 951
Default

Folks,

Finally got the C3 to my mechanic on Wednesday. He couldn't find anything wrong. It was behaving itself perfectly.

Took it for a spin in the sun an hour ago and the problem returned. I could feel the car being held back,then occasionally surge forward as the brakes freed up, then felt it held back again,

Front wheels boiling hot. Rear wheels not too warm, ok.

This time the brake pedal is travelling about 4 inches more before the brakes engage. The front calipers are definitely the only ones affected and they remain engaged. I guess that would explain the extra distance the brake pedal is travelling now.

I am going to get the master cylinder replaced regardless now. Before I do so, are there any further opinions from you all?
Ringmaster is offline   Reply With Quote
Old 26-05-18, 06:51 PM   #8
Duffy3074
Senior Member
Classic Audi Club Member
 
Join Date: Aug 2015
Location: Dalgety Bay, Fife
Posts: 1,455
Default

It’d be my shout still

Duffy3074 is offline   Reply With Quote
Old 26-05-18, 06:54 PM   #9
John.
4 ring whore!
Classic Audi Club Member
 
John.'s Avatar
 
Join Date: Mar 2011
Location: Scottish Borders.
Posts: 6,470
Default

On my CQ the underbonnet temp gets pretty high I think.....and this is when my brakes would bind.
Does yours have a vacuum servo, if yes it would be easy enough to pull of the vacuum pipe when they're binding and see if they release ?.......if yes then servo not good. If you have vacuum servo!

John. is offline   Reply With Quote
Old 26-05-18, 08:32 PM   #10
Ben
4 ring whore!
Classic Audi Club Member
 
Join Date: Mar 2008
Location: Stockport
Posts: 2,004
Default

Quote:
Originally Posted by Duffy3074 View Post
Itd be my shout still


+1


Keep the old master cylinder and open it up to see.
Ben is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT. The time now is 03:57 AM.

Powered by vBulletin®
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.
Copyright ©2007-2008 Classic Audi | Site by Roadrunna