Brakes slowly locking up.
Thread Starter
Instructor
Joined: Jun 2010
Posts: 131
Likes: 0
From: Shreveport Louisiana
Brakes slowly locking up.
1991 L98
At first I noticed the ABS didn't come on and the brakes were real weak, after some driving ABS eventually came back on.
After parking and restarting after a while, brakes seemed to be dragging after driving for any small distance.
Eventually The brakes were as stiff as if I were standing on them.
ABS never came back on.
I shut the car off and unhooked the battery for 10 minutes thinking it might be electrical.
At first it drove fine, but then it happened again.
The pedal was very stiff when I parked it for good last night, with the brakes locked up completely.
I noticed that there is brake fluid leaking between the master cylinder and the booster.
Any ideas?
At first I noticed the ABS didn't come on and the brakes were real weak, after some driving ABS eventually came back on.
After parking and restarting after a while, brakes seemed to be dragging after driving for any small distance.
Eventually The brakes were as stiff as if I were standing on them.
ABS never came back on.
I shut the car off and unhooked the battery for 10 minutes thinking it might be electrical.
At first it drove fine, but then it happened again.
The pedal was very stiff when I parked it for good last night, with the brakes locked up completely.
I noticed that there is brake fluid leaking between the master cylinder and the booster.
Any ideas?
Pro
Joined: Oct 2005
Posts: 721
Likes: 1
From: Charlotte NC, behind someone going 10 under the speed limit
My 88 has been doing this for a while now, you have to drive it about 20 minutes before it happens. I think it's a bad master cylinder, affected by engine heat. Haven't replaced yet, tho. They aren't holding very hard, just enough to get the wheels hot and hold it still on a slight incline.
Drifting
Joined: Oct 2008
Posts: 1,936
Likes: 92
From: Rochester Hills Michigan
I had the brakes slowly lock up on my '65. The smaller port to the left in this picture was plugged. That port allows brake fluid to expand back into the reservoir when it gets hot. If the port is plugged, the expanding brake fluid applies the brakes, which gets the fluid hotter, which applies the brakes harder, and so on.
Team Owner
Joined: Sep 2003
Posts: 20,179
Likes: 673
From: Freedom is never more than one generation away from extinction.
St. Jude '03 thru '24
I'm not discounting the leak.
Will pulling the ABS fuse be worthy of a quick test at this point?
I personally wouldn't drive over the speed the E-brake could stop me at this point.
Will pulling the ABS fuse be worthy of a quick test at this point?
I personally wouldn't drive over the speed the E-brake could stop me at this point.
Thread Starter
Instructor
Joined: Jun 2010
Posts: 131
Likes: 0
From: Shreveport Louisiana
