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Medtner3 |
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#1
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Member ![]() ![]() Group: Members Posts: 187 Joined: 7-July 20 From: Cedar Park Member No.: 24,467 Region Association: None ![]() |
Just rebuilt my rear calipers with seals from PMB Performance. Using a vacuum brake bleeder I started with the right rear caliper lower bleeder screw ( I have two screws) and initially pulled about an inch of brake fluid with lots of bubbles and then zip. I get zero brake fluid now.
What could cause this? I have no signs of any leaks and the brakes were not bad before I rebuilt the calipers. I read somewhere that I might need to bleed the proportioning valve or even pump into the caliper some brake fluid through the top bleeder ? I ordered a Motive pressure bleeder which arrives in a few days Attached image(s) ![]() ![]() ![]() |
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davep |
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#2
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914 Historian ![]() ![]() ![]() ![]() ![]() Group: Benefactors Posts: 5,300 Joined: 13-October 03 From: Burford, ON, N0E 1A0 Member No.: 1,244 Region Association: Canada ![]() ![]() |
On a caliper with two bleed nipples, the top is the bleed, and the bottom is a drain; only bleed with the top nipple. Air bubbles rise you know.
When bleeding the system, keep checking the reservoir to be sure it is full by removing the cap and looking down inside. The reservoir is divided by a half barrier into front & rear so an external glance may not reveal that the other half is empty. If a half does empty, then you will have to do a long bleed to ensure any air introduced at the reservoir is removed. Pedal bleeding ensures that high pressure is able to be achieved, and it also crushes bubbles and helps them move through the system; keeping them from being trapped within things like the pressure regulator. So I like to finish a bleed with pedal bleeding after using either a vacuum bleed or an air pressure bleed method. |
Medtner3 |
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#3
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Member ![]() ![]() Group: Members Posts: 187 Joined: 7-July 20 From: Cedar Park Member No.: 24,467 Region Association: None ![]() |
On a caliper with two bleed nipples, the top is the bleed, and the bottom is a drain; only bleed with the top nipple. Air bubbles rise you know. When bleeding the system, keep checking the reservoir to be sure it is full by removing the cap and looking down inside. The reservoir is divided by a half barrier into front & rear so an external glance may not reveal that the other half is empty. If a half does empty, then you will have to do a long bleed to ensure any air introduced at the reservoir is removed. Pedal bleeding ensures that high pressure is able to be achieved, and it also crushes bubbles and helps them move through the system; keeping them from being trapped within things like the pressure regulator. So I like to finish a bleed with pedal bleeding after using either a vacuum bleed or an air pressure bleed method. Okay the first problem was my master went dry because it was so discolored from ATE super blue that I thought it had fluid. How do I bleed now .. do I need to bleed the master? |
iankarr |
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#4
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The wrencher formerly known as Cuddy_K ![]() ![]() ![]() ![]() Group: Members Posts: 2,567 Joined: 22-May 15 From: Heber City, UT Member No.: 18,749 Region Association: Intermountain Region ![]() ![]() |
On a caliper with two bleed nipples, the top is the bleed, and the bottom is a drain; only bleed with the top nipple. Air bubbles rise you know. When bleeding the system, keep checking the reservoir to be sure it is full by removing the cap and looking down inside. The reservoir is divided by a half barrier into front & rear so an external glance may not reveal that the other half is empty. If a half does empty, then you will have to do a long bleed to ensure any air introduced at the reservoir is removed. Pedal bleeding ensures that high pressure is able to be achieved, and it also crushes bubbles and helps them move through the system; keeping them from being trapped within things like the pressure regulator. So I like to finish a bleed with pedal bleeding after using either a vacuum bleed or an air pressure bleed method. Okay the first problem was my master went dry because it was so discolored from ATE super blue that I thought it had fluid. How do I bleed now .. do I need to bleed the master? I would. Since it's gone dry, i'd just start from scratch... – Bleed the master (in the car is fine...see video link above). Use pedal only...and put a block or something down to make sure you don't hyper-extend the pedal and damage the seals inside the MC). When no bubbles are coming through... – Put a quart of fluid in the motive, hook it up and pressurize to 5-10 PSI. Use a rubber mallet to rap on the caliper and dislodge air bubbles while bleeding. – Bleed from the top screws LR, RR, RF, LF. – Finish with a pedal bleed all the way around. If you don't have a firm pedal, do it again until you do. If it's firm enough to drive, but not perfect, that's kind of typical. Just carefully drive it on a bumpy road for a bit, then bleed again. Good luck and be safe! |
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