Please help! No rear brakes 93 Z28
01-07-2009, 09:49 AM
#1
Launching!
Thread Starter
iTrader: (5)
Join Date: Jun 2007
Posts: 266
Likes: 0
Received 0 Likes
on
0 Posts
Please help! No rear brakes 93 Z28 Hello I have replaced the pads and rotors as well as the master cyl. I have bled and bled and bled and the rear brakes still dont have enough to over power the car in gear (rear up on jack stands/ in gear).
Does it have soething to do with the parking brake adjustment?
thanks, Josh.
PS I have bled the ABS module, then drove it and cycled the solinoids and bled again... and again. No bubbles.
Does it have soething to do with the parking brake adjustment?
thanks, Josh.
PS I have bled the ABS module, then drove it and cycled the solinoids and bled again... and again. No bubbles.
01-08-2009, 08:28 AM
#2
TECH Enthusiast
iTrader: (1)
Join Date: Sep 2005
Location: Chicagoland
Posts: 628
Likes: 0
Received 0 Likes
on
0 Posts
Josh, Can you please clarify your test method. I think I understand that you have the rear up on jack stands, it's in gear and then what.... Are you turning the wheel by hand, or with the motor, or ???
01-09-2009, 02:18 PM
#3
Launching!
Thread Starter
iTrader: (5)
Join Date: Jun 2007
Posts: 266
Likes: 0
Received 0 Likes
on
0 Posts
With the engine in gear and the transmission engauged (drive) the brakes will not stop the wheels from turning, although I can feel then grabing slighly.
My dad has a CJ5 with cadilac rear disc and he tells me his brakes wont work if the e-brake is out of adjustment. Thats why I asked that.
Is there a wire I can jump to get the ABS module to cycle? Maybe theres stil air in there, but Ive bled them untill clean fluid comes out .
Thanks, Josh.
My dad has a CJ5 with cadilac rear disc and he tells me his brakes wont work if the e-brake is out of adjustment. Thats why I asked that.
Is there a wire I can jump to get the ABS module to cycle? Maybe theres stil air in there, but Ive bled them untill clean fluid comes out .
Thanks, Josh.
01-09-2009, 08:54 PM
#4
TECH Enthusiast
iTrader: (1)
Join Date: Sep 2005
Location: Chicagoland
Posts: 628
Likes: 0
Received 0 Likes
on
0 Posts
The e-brake and the regular breaks are two separate systems, therefore I do not think any adjustment to the e-brake would make an improvement. However, I do not have experiance with the LT-1 Rears.
One of the advantages of the LT-1 ABS module is that it has a bleeder screw built into it so you can bleed it like a caliper.
Did you bench bleed the master? A lot of air can be trapped in it and it takes forever to bleed it when it is on the car. You may consider taking the master back off and re-bleeding it. Then bleed the entire system again.
Do the rear caliper float freely on the caliper guide pins? Did you grease them up prior to re-assembling everything?
Another thing to consider: The hard brake line to the rear has been crimped which restricts fluid flow, therefore the rear calipers do not see full line pressure. Inspect the brake lines from front to rear and look for damage.
One of the advantages of the LT-1 ABS module is that it has a bleeder screw built into it so you can bleed it like a caliper.
Did you bench bleed the master? A lot of air can be trapped in it and it takes forever to bleed it when it is on the car. You may consider taking the master back off and re-bleeding it. Then bleed the entire system again.
Do the rear caliper float freely on the caliper guide pins? Did you grease them up prior to re-assembling everything?
Another thing to consider: The hard brake line to the rear has been crimped which restricts fluid flow, therefore the rear calipers do not see full line pressure. Inspect the brake lines from front to rear and look for damage.
01-11-2009, 10:11 PM
#5
Launching!
Thread Starter
iTrader: (5)
Join Date: Jun 2007
Posts: 266
Likes: 0
Received 0 Likes
on
0 Posts
Yes, the pins are greased and the calipers are sliding smooth.
The master was bench bled. The abs module was bled but something is making me think the problems still lies there. I had the rear-end out of the car last weekend to set up my new gears and the brake lines where not showing any damage.
Ive been reading about having to use a techII scan tool to properly bleed the abs by cycling the solinoids. I dont think driving and banging on the brakes is enough to do it.
I think my next step is going to be removing the calipers and see if the pistons are working properly.
The master was bench bled. The abs module was bled but something is making me think the problems still lies there. I had the rear-end out of the car last weekend to set up my new gears and the brake lines where not showing any damage.
Ive been reading about having to use a techII scan tool to properly bleed the abs by cycling the solinoids. I dont think driving and banging on the brakes is enough to do it.
I think my next step is going to be removing the calipers and see if the pistons are working properly.
