dbo_texas
07-06-2024, 04:26 PM
I managed to fix 2 issues I had with the brakes - leaking banjo fittings at the master cylinder AND a leaking "tee" joint in the rear. Those issues were detailed on my build thread HERE (https://thefactoryfiveforum.com/showthread.php?40632-ATX-MKIV-9644-Coyote-Build-Thread-(Index-Post-136)&p=557857&viewfull=1#post557857) but I believe are resolved finally.
After fixing both of those issues, I bench bled the master cylinder again (attached to a hydroboost setup from Forte), then went through Wilwood's recommended bleeding process for the calipers. Started with PS rear outboard upper bleeder, then moved to the inboard upper bleeder. Then did DS rear (both upper bleeders), then PS front (single upper bleeder), then DS front (single upper bleeder). Bleeding each caliper seemed to go smoothly - I had a helper and we did the old school method by cracking the bleeder, depressing the pedal, then closing the bleeder and letting off the pedal slowly. Did this repeatedly until no bubbles on any of the bleeder valves (going one at a time). This method seemed to work a lot better than using the vacuum bleeder kit I had. After just a few pumps on each bleeder, it ran fluid out the bleeder with no more bubbles.
The reservoirs never ran dry during bleeding - I kept filling them as the levels lowered (separate front/rear circuits). All good so far, or so I thought.
After doing all 4 corners, I can still apply pedal pressure and it goes all the way to to floor with not much resistance. I'm not finding leaks anywhere. I went through all the joints and re-tightened them just to make sure. But still no significant pedal pressure. I tried holding pedal pressure for a few minutes, and still no leaks anywhere. Reservoir levels are steady (not dropping with subsequent pedal presses).
What am I missing here? Even with the hydroboost not powered yet (by the power steering pump), shouldn't I still get a firm pedal and NOT be able to press it all the way to the floor? I also checked the calipers and the pistons don't seem to be closing all the way....the pads barely rub the rotor. Do I still have air trapped in the circuits somewhere? Or maybe even the master cylinder still? Any other ideas how to trouble shoot this? I've wasted hours and hours on these damn brakes.....nothing but problems at every step. I'm ready to pull my hair out.
Any suggestions on how to trouble shoot this would be massively appreciated. I'm about ready to throw in the towel and call a professional to help me with this issue.
Here's a pic of my master cylinder setup. The MC & hydroboost are from Forte. I believe he told me it was from a 1999 Chevy pickup truck but I'm not sure what specific master cylinder is mounted to it. If anyone has this specific setup (with Wilwood brakes) I'd love to hear how you went about bleeding and testing the system.
https://thefactoryfiveforum.com/attachment.php?attachmentid=200828&d=1718936099
After fixing both of those issues, I bench bled the master cylinder again (attached to a hydroboost setup from Forte), then went through Wilwood's recommended bleeding process for the calipers. Started with PS rear outboard upper bleeder, then moved to the inboard upper bleeder. Then did DS rear (both upper bleeders), then PS front (single upper bleeder), then DS front (single upper bleeder). Bleeding each caliper seemed to go smoothly - I had a helper and we did the old school method by cracking the bleeder, depressing the pedal, then closing the bleeder and letting off the pedal slowly. Did this repeatedly until no bubbles on any of the bleeder valves (going one at a time). This method seemed to work a lot better than using the vacuum bleeder kit I had. After just a few pumps on each bleeder, it ran fluid out the bleeder with no more bubbles.
The reservoirs never ran dry during bleeding - I kept filling them as the levels lowered (separate front/rear circuits). All good so far, or so I thought.
After doing all 4 corners, I can still apply pedal pressure and it goes all the way to to floor with not much resistance. I'm not finding leaks anywhere. I went through all the joints and re-tightened them just to make sure. But still no significant pedal pressure. I tried holding pedal pressure for a few minutes, and still no leaks anywhere. Reservoir levels are steady (not dropping with subsequent pedal presses).
What am I missing here? Even with the hydroboost not powered yet (by the power steering pump), shouldn't I still get a firm pedal and NOT be able to press it all the way to the floor? I also checked the calipers and the pistons don't seem to be closing all the way....the pads barely rub the rotor. Do I still have air trapped in the circuits somewhere? Or maybe even the master cylinder still? Any other ideas how to trouble shoot this? I've wasted hours and hours on these damn brakes.....nothing but problems at every step. I'm ready to pull my hair out.
Any suggestions on how to trouble shoot this would be massively appreciated. I'm about ready to throw in the towel and call a professional to help me with this issue.
Here's a pic of my master cylinder setup. The MC & hydroboost are from Forte. I believe he told me it was from a 1999 Chevy pickup truck but I'm not sure what specific master cylinder is mounted to it. If anyone has this specific setup (with Wilwood brakes) I'd love to hear how you went about bleeding and testing the system.
https://thefactoryfiveforum.com/attachment.php?attachmentid=200828&d=1718936099