I quit. I give up. Stick a fork in me.

[bstuke]

You would think simple hydraulics would not kick the butt of a decently educated person with a good amount of common sense. It sure seems like it today.

I redid my brakes, have them bled, and now the fronts lock up and it feels like the backs do not work at all. At 45-50 MPH with Kumho XS's kinda warm, I can easily modulate the brake to where the fronts smoke.

AAAARRRGGGHHHH!!!!!!

The only other possibility is that the pads are just saturated, or slick, or something.

Can I take the pads off and dry sand them with wet/dry 150 or something to knock the sheen of if they are shiny?

Basically I am out of options and time, and will have to bag going to Nashville if I can't get the backs to grab at least a little.

[Bob Cowan]

You can sand the pads if they're glazed. Don't get them wet, though. The best thing to use is a fine grit, like 120-180. Lay the sandpaper on a sheet of glass (very flat) and rub the pads over them in a gently circular motion. You don't need to remove much material.

If you have at some point switched to a differant type of pad, you'll also need to resurface the brake rotor. I managed to track down a brake hone, but you can use fine grit sanding wheel in a drill motor, too.

Get your hands on a brake pressure gauge. Find out what the pressure is front and rear. If you're not getting any pressure to the rear caliper, that will really help you.

[DWIGHT]

If you think you have oil or brake fluid on them you can clean them with dics brake cleaner.

Dwight

[Wade Chamberlain]

do you still have the factory combination proportioning/shuttle valve? If so, it's possible to have it shift while bleeding and cut off flow to the rears.

[bstuke]

Originally Posted by DWIGHT

If you think you have oil or brake fluid on them you can clean them with disc brake cleaner.

Thanks Dwight, didn't think of that.

Originally Posted by Wade Chamberlain

do you still have the factory combination proportioning/shuttle valve? If so, it's possible to have it shift while bleeding and cut off flow to the rears.

I don't Wade, no prop valves anywhere. I did have one in the front most of the season to try and tackle the problem. It seems that doing that helped, but there is still a problem. Now that it is out I have nothing, or what seems like nothing but fronts.

Originally Posted by Bob Cowan

You can sand the pads if they're glazed. Don't get them wet, though. The best thing to use is a fine grit, like 120-180. Lay the sandpaper on a sheet of glass (very flat) and rub the pads over them in a gently circular motion. You don't need to remove much material.

If you have at some point switched to a different type of pad, you'll also need to resurface the brake rotor. I managed to track down a brake hone, but you can use fine grit sanding wheel in a drill motor, too.

Get your hands on a brake pressure gauge. Find out what the pressure is front and rear. If you're not getting any pressure to the rear caliper, that will really help you.

Thanks Bob. I said wet/dry because it doesn't shed as much. They had 320/400/600 so I got the 320 and knocked the glaze of the pads. No luck. I am going to pull the fronts today and hit them with 320. Maybe they are just glazed, and grabbing and not linear.

The main problem is that the brakes have been bad for so long, I have no concept of what good is.

I do know what is in the footbox is coming out, and wilwood pedals are going in. And I may just replace all the brake lines front to back. And I will most likely go to Brembo 4 piston calipers on the front.

And yes I agree on the gauge as well. thinking of something like this over the winter:


Thanks for the feedback!

[M DOUGHERTY]

bstuke
give me a ring
717-773-5624
lets talk Brakes
Later
mark D

[JKleiner]

Originally Posted by M DOUGHERTY

bstuke
give me a ring
717-773-5624
lets talk Brakes
Later
mark D

There ya go...You're gonna get it figured out now

Jeff

[Bob Cowan]

I'm not a big fan of in dash brake gauges. It adds a lot line for the brakes, and that makes them more difficult to bleed. And, I don't like the idea of two high pressure hydraulic lines in the cockpit.

[mmarshall]

They also make a pressure gage that you stick between the brake pads and read pressure to the pads. I used one and found a bad caliper.

You mentioned changes to the brake system. What changes did you make?

Better hurry as we have to leave for Nashville tomorrow!

[bstuke]

I'll be there. I won't have brakes but I will be there! Posted info in the other thread...

[bstuke]

Ok sanding the glaze off the rotors help a little more. Used an orbital sander, and ran the car in first on jacks without the calipers on.

If I had more time I might try a set of Carbotech XP12's on the back, but I am going to hold off and either put in Wilwood Pedals, or Tilton pushrod to balance bar adapters and dual MC.

Mark D was awesome help as always, thanks!

[mmarshall]

Glad you got it together. I just finished putting the Hankooks on and will be loading up in the AM. See ya in Nashville!

[M DOUGHERTY]

I love the brake bias gauges in the cockpit. there is no better brake tuning tool than that.
If you dont know your preasures then everything else is a educated guess. I have been running them for years.