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bobtsgt
04-23-2007, 09:35 PM
Well I just installed fresh rebuilt PBR GT calipers up front along with a line lock. I did have the master cylinder off to do the line lock and put new Russell SS lines up front. When I push the brakes in with the car on the pedel will go to the floor and the lines will go toward the struts like its getting sucked thin.
We bled and power bled all 4 corners and the lines still flex and the pedel still goes to the floor. They only go to the floor with the car on. There is some pressure before it hits the floor though. With the car off it has plenty of pressure behind it. We cannot figure out why the lines are flexing so much and why the pedel goes to the floor with the car on. Any help will be greatly appreciated. Thanks.

5.0calypso93lx
04-23-2007, 10:03 PM
Did you already try the MC?

bobtsgt
04-23-2007, 10:17 PM
not yet. we just did the vacuum power bleed so far. I also power bled the MC at those two valves. I guess Friday I will be taking off the MC and bleed it manually. Just hopeing it was an easy fix but I was wrong. What about power bleeding with the pedal pushed in?

Black Horse
04-23-2007, 10:37 PM
How are you "power" bleeding?

It definately sounds like massive air in the lines (thats why the lines are moving) - start with the Passengers side rear, then do the Drivers side rear, then the Passengers side front, then the Drivers side front. (works from furthest away to the closest to the MC).

Are you sure your MC has the capacity for the upgraded calipers?

5.0calypso93lx
04-24-2007, 07:57 AM
How are you "power" bleeding?

It definately sounds like massive air in the lines (thats why the lines are moving) - start with the Passengers side rear, then do the Drivers side rear, then the Passengers side front, then the Drivers side front. (works from furthest away to the closest to the MC).

Are you sure your MC has the capacity for the upgraded calipers?

He pulled the MC off, and forgot to bench bleed the MC itself before it went back on. His stock 96 MC and booster should be fine with those pbr calipers. I just think there is air in the MC, and if he pulls it off and bench bleeds the MC, he should be fine.

bobtsgt
04-24-2007, 08:33 AM
How are you "power" bleeding?

It definately sounds like massive air in the lines (thats why the lines are moving) - start with the Passengers side rear, then do the Drivers side rear, then the Passengers side front, then the Drivers side front. (works from furthest away to the closest to the MC).

Are you sure your MC has the capacity for the upgraded calipers?
yeah the MC should be fine. many people have done the upgrade already. I did do the RR then LR then RF then LF. I hooked the vacuum bleeder up to each individual calipers, cracked the bleeder open about 1/4 turn, then let the machine do the work. Even though it didn't fix the problem atleast I know I have clean fluid in the lines now :D


He pulled the MC off, and forgot to bench bleed the MC itself before it went back on. His stock 96 MC and booster should be fine with those pbr calipers. I just think there is air in the MC, and if he pulls it off and bench bleeds the MC, he should be fine.

Yeah I think I am going to take it off Friday and do the bench bleed procedure . If I can remember I may go ahead and rebuild it too.

theyallslow
04-24-2007, 09:34 AM
bench bleed is easy, let me know when you are going to do it and i will give you some help.

bobtsgt
04-24-2007, 09:45 AM
more then likely be Friday since we got class tonight and thursday

theyallslow
04-24-2007, 02:32 PM
I am kool with that. i will talk with you about in class.

bobtsgt
04-24-2007, 04:17 PM
that works. call me if you need a ride tonight

theyallslow
04-24-2007, 05:04 PM
ok...

bobtsgt
04-25-2007, 08:49 AM
also starting to think that mabey since the line loc is above the MC that its still getting air trapped in it. I guess we will find out after Friday.

theyallslow
04-25-2007, 09:32 AM
also starting to think that mabey since the line loc is above the MC that its still getting air trapped in it. I guess we will find out after Friday.

that was your idea? jk I will see you firday to help.

Black Horse
04-25-2007, 09:42 AM
If you guys can't get it worked out, I have a pressure bleeder that forces fluid from the MC side. I can bleed my brakes at the track by myself in 15 minutes.

bobtsgt
04-25-2007, 09:55 AM
thanks Dave. Is a pressure bleeder the same as a vacuum power bleeder? where you hook up an air hose to it and crack the bleeder?

theyallslow
04-25-2007, 12:20 PM
thanks Dave. Is a pressure bleeder the same as a vacuum power bleeder? where you hook up an air hose to it and crack the bleeder?

no they are not the same. you can put air to some and others work off you power. they work very well and fast. I would like to try it out on a 96 gt+ car. would like to see how it works.

bobtsgt
04-25-2007, 02:12 PM
alright I read up on pressure bleeders. whats your day look like for friday after 5 and saturday Dave? I may want to try this first just for the hell of it.

Black Horse
04-25-2007, 05:45 PM
I'm tied up Friday and Saturday. I'll throw it in the car Sunday and bring it to the cruise. I will need it back right away.

Its a Motive Products pressure bleeder

www.motiveproducts.com

I think Summitt sells them, as well as a lot of the oval/road race specialty shops.

In my opinion, it's better than sliced bread. As often as I change fluid and bleed, it has become one of my most useful tools!

bobtsgt
04-26-2007, 08:36 AM
I'm going to see if I can get one closer by Saturday. The car needs to be able to stop Saturday night or else I can't drive it to the cruise. I'll let you know Saturday if I'll need it or not. Thanks Dave.

Black Horse
04-26-2007, 08:59 AM
I'll be home all evening today (Thursday) if you want to take the long drive out towards Oxford.

bobtsgt
04-26-2007, 09:10 AM
I would love to but I don't get out of welding class til 9:30PM. Plus we don't have any jobs up north today so I can't swing by "on the clock" :D thanks anyways though.

5.0calypso93lx
04-26-2007, 09:20 AM
I'm tied up Friday and Saturday. I'll throw it in the car Sunday and bring it to the cruise. I will need it back right away.

Its a Motive Products pressure bleeder

www.motiveproducts.com

I think Summitt sells them, as well as a lot of the oval/road race specialty shops.

In my opinion, it's better than sliced bread. As often as I change fluid and bleed, it has become one of my most useful tools!

Dave, which of those bleeders in their products section do you recomend? I see one that is Ford specific?

bobtsgt
04-26-2007, 09:26 AM
I've read that some guys go get a extra cap from a junkyard and use a 3/8 adapter on it. That way you know its sealed and won't screw up the thread. I wonder if cracker has one on the shelf

Black Horse
04-26-2007, 10:17 AM
I believe I use the Motive 0101 Universal unit.

You can cobble up a pressure bleeder yourself by screwing a quick disconnect into an old MC cap and attaching your air hose. But CAUTION use no more than 5 or 6 psi MAX of incoming air. And be sure to keep an eye on the MC reservoir to be sure it doesn't go low - pressure bleeding will empty a MC in a big hurry and if you are pushing with air you will inject air into the lines very quickly. Thats why I love the Motive unit - fill it full of brake fluid and pump it up, only pressurized fluid makes it to the Master Cylinder - no air.

I know Cracker don't sell these, I asked him once and he looked into it, but I don't think he can get them.

bobtsgt
04-26-2007, 10:31 AM
damn. I guess I could configure one like that. I have small regulators at work I can "borrow"

bobtsgt
04-26-2007, 10:44 AM
what about making one out of a chemical sprayer since its still a hand pump action?

bobtsgt
04-26-2007, 11:09 AM
found this site. pretty helpful http://www.bmw-m.net/TechProc/bleeder.htm

Black Horse
04-26-2007, 12:11 PM
Garden sprayer or home-built pump up might work once or twice - just remeber, brake fluid does strange stuff to rubber seals like o-rings. Thats why I went with the Motive - it's built right to do the right job.


Bob: here is what I would do (you'll need someone else to help):

Take the lines loose from the MC, fill it by pumping the pedal until fluid squirts out the ports just like you would do if you were bench bleeding (wipe rags around everything so no fluid gets on anything painted).

Re attach the lines and start bleeding using the pedal method for each wheel one wheel at a time.

If you have never done a pedal bleed - here is the general jist:
With your buddy in the car, open the bleed screw, have him slowly depress the pedal until it hits the floor, shut the bleed screw, have him raise the pedal and do it over and over and over again. The tricky part is to not let the pedal raise at all before you get the bleed screw shut off.

On the final pedal travel I try to shut the bleed screw off while he is in mid stroke to assure no air bubbles.

That should do it!

Remeber - brake fluid on paint is a very, very bad thing!

bobtsgt
04-26-2007, 12:24 PM
thats not a bad idea too. I think I'll try that method first. I've bled the 4 corners already so I'm use to that. also found out what fluid does to fresh painted calipers. oh well. most of the paint is still on there :D

Black Horse
04-26-2007, 12:40 PM
thats not a bad idea too. I think I'll try that method first. I've bled the 4 corners already so I'm use to that. also found out what fluid does to fresh painted calipers. oh well. most of the paint is still on there :D


What you don't want to see it what it does to paint on fenders......

bobtsgt
04-26-2007, 12:42 PM
haha not really. I got a garbage bag full of rags plus some fender covers so I should be good to go. although I could use a new paint job :D

Black Horse
04-27-2007, 08:15 AM
Well?

bobtsgt
04-27-2007, 09:10 AM
well we shall find out tonight. had class last night so no workie on the car.

bobtsgt
04-30-2007, 09:09 AM
All fixed. Brian came over and we got it all squared away.

5.0calypso93lx
05-15-2007, 02:16 PM
Garden sprayer or home-built pump up might work once or twice - just remeber, brake fluid does strange stuff to rubber seals like o-rings. Thats why I went with the Motive - it's built right to do the right job.


Bob: here is what I would do (you'll need someone else to help):

Take the lines loose from the MC, fill it by pumping the pedal until fluid squirts out the ports just like you would do if you were bench bleeding (wipe rags around everything so no fluid gets on anything painted).

Re attach the lines and start bleeding using the pedal method for each wheel one wheel at a time.

If you have never done a pedal bleed - here is the general jist:
With your buddy in the car, open the bleed screw, have him slowly depress the pedal until it hits the floor, shut the bleed screw, have him raise the pedal and do it over and over and over again. The tricky part is to not let the pedal raise at all before you get the bleed screw shut off.

On the final pedal travel I try to shut the bleed screw off while he is in mid stroke to assure no air bubbles.

That should do it!

Remeber - brake fluid on paint is a very, very bad thing!

This is without using a pressure bleeder right?

How does the pressure bleeder work? Do you just remove the MC cap, and screw that cap that comes attached to the bottle on instead, and just start pumping?

bobtsgt
05-15-2007, 02:57 PM
I wrote Brandon about how the vacuum bleeder works and not the pressure one. you can take an old cap and put a 3/8" fitting on it, then use a regulator to put 5psi on the cap and let the pressure of the air push the fluid through.