Messages

1

Maintenance / Re: Front Disc Brakes dragging...

« on: July 06, 2009, 06:34:16 PM »

No,
Doesn't stop in the same position.
There seems to be a consistent resistence/drag on the Driver's side.
Passenger side now spins pretty freely.

I drove the car all weekend and the front wheels do not seem to be getting excessively hot like they were. I need to jack mit up again and check now that I put a few miles on it after the hydraulic fix.

I plan to dis-assemble the brakes and make sure that the calipers move freely. Might need to grease the pins or whatever.
I am pretty happy that the hydraulic problem is fixed.

Probably need to also re-grease the bearings given that some of the grease melted out.

2

Maintenance / Re: Front Disc Brakes dragging...

« on: July 02, 2009, 11:30:56 PM »

It is a threaded tip on the end of the pushrod. Perhaps it shifted. Once I measure the depth and figure what length I need, I will locktite it.

BTW, Before I could barely turn the front tires about 1/2 turn with a hard push.
Now the passenger side does 2.5 turns, but the driver side about 1 turn.
How much drag is normal on disc brakes?

3

Maintenance / Re: Front Disc Brakes dragging...

« on: July 02, 2009, 11:10:15 PM »

OK,
Losening the MC released the pressure.
So, I pulled off the MC (still left Hydraulic lines connected, and pulled out the pushrod from the PB.

(A little history). I had a good hotrod shop fix my brakes last year. They replaced almost everything but went with non original parts.
Anyway, the pushrod is adjustable on mine. Was set at about 4 in, but would shorten to about 3. So I set it as short as possible and put the MC back on.

No drag. Drove the car about 5 miles. Can still lockup the brakes, but they engage later in the brake travel. Was able to touch the bearing caps (before the bearings got soo hot the grease was melting out).
I might need to pull the MC again and measure how deep the pushrod needs to go in before it meets the plunger (or whatever it is called).

Since the brakes worked for a while, I wonder if something changed in the MC over the first few hundred miles?

Anyway, thanks for the help.
Reeko

4

Maintenance / Re: Front Disc Brakes dragging...

« on: July 02, 2009, 10:23:52 AM »

Again, can't be pedal play since I disconnected the pedal and the drag did not go away.
I think the brakes were fine for the last 500 miles as I only noticed the drag recently. Could they have gotten progressively worse?
(I only noticed that burning smell and the earing grease only started to melt out the last time I drove).


They drag now even when cold. I can only spin the front tires about 3/4 turn by hand unless I release some pressure in which case they spin about 3 turns for the same effort.

5

Maintenance / Re: Front Disc Brakes dragging...

« on: July 02, 2009, 03:50:15 AM »

Ok,
If loosening the MC on the PB releases the pressure, what does that tell me?
Bad MC?

6

Maintenance / Re: Front Disc Brakes dragging...

« on: July 02, 2009, 12:03:27 AM »

OK,
Yes the lines are all new. The problem must be before the distribution block since both front brakes drag equally.

I will try loosening the MC off the PB.
How is that differnt from disconnecting the Brake Pedal, doesn't that ensure that there is slack in the linkage?
So, if loosening the MC causes the brakes to release, what does that indicate, Bad MC?

I suppose another check would be to release the pressure both sides of the Holdoff valve and see which side is the problem.
If the Holdoff is stuck closed and not releasing pressure, then opening the line between the MC and the Holdoff vavle will have no effect.

7

Maintenance / Re: Front Disc Brakes dragging...

« on: July 01, 2009, 10:55:20 PM »

Yes,
In fact, I pulled the pin on the brake pedal so that the pushrod was disconnected and had complete slack. Still the brakes were dragging.
So not the pedal.

I am planning to replace the Metering (proportioning) valve on the front to see if it might be the problem. (The valve on the Driver Side below the MC that connects only to the Front Disc Lines.)

8

Maintenance / Front Disc Brakes dragging...

« on: July 01, 2009, 06:37:54 PM »

Hi, new guy here...
Anyway, I have recently completed restoration on my 69 Camaro.
As pert of that, I added front disc brakes. Replaced the Master cylinder etc... New calipers...

Anyway, the brakes were working fine for a while (500 miles on it at least).
Recently however, the front brakes are dragging horribly.

I figure that if I had the wrong valves or Master cylinder, they would have had the problem from the start.
I know it is hydraluic because opining the bleeder on the brakes makes the wheels turn fine. But the next time I pump them up, they drag again.

Also, I don't think it is the brake pedle, as I pulled the pin on the pushrod and it still drags. Also note that it drags even if the car is not running.

Right now I suspect the Front Disc Holdoff valve (some call it a proportioning valve). I Believe the purpose of this valve is to prevent pressure from going to the discs until some set pressure is reached. Would my problems happen if that were stuck open?

I would think that if I had the wrong MC (with a check valve in the front) that I would have had this problem immediatly.

Any suggestions?
Thanks
Reeko