Bad Master Cylinder?

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CalSgt

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Perhaps try bleeding the master cylinder like this before hooking the lines up, this is the generic instructions that come with new master cylinders. They also come with a few clear plastic pieces of tubing and some fittings.

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AZ Highlander

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Perhaps try bleeding the master cylinder like this before hooking the lines up, this is the generic instructions that come with new master cylinders. They also come with a few clear plastic pieces of tubing and some fittings.

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Thanks Casey. I was hoping to avoid buying the kit to bleed back into itself, but I may need to bite the bullet. Bleeding without it isn't working for me yet.
 

CalSgt

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Thanks Casey. I was hoping to avoid buying the kit to bleed back into itself, but I may need to bite the bullet. Bleeding without it isn't working for me yet.
Good luck sir... Even with the bench bleed kit I swear I pumped mine about a thousand times before the bubbles stopped.
 

idahovette

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AND... slow easy pumps..ya can't be in a hurry. Give it a little time to rest between pumps.
 

AZ Highlander

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The friend I got the master from told me to remove the lines off the master and use my fingers over the holes to prevent air from getting sucked back in while my son pumps the pedal. Will try that technique later this afternoon. Thanks for the tips guys!
 

AZ Highlander

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So, that worked. Got the master to bleed.
Was obviously sucking air back into the master through the rear line before. Finger was a one way valve over the rear line hole. Success!
But the saga continues….
Went to bleed the right rear, fluid started coming out! Success! Then I heard a leak. Wheel cylinder decided to give way. See below.
Why did this happen? First time bleeding drums. Thanks for taking the time to help me figure out how to keep the truck on the road
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AZ Highlander

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These are brand new wheel cylinders by the way. What did I do wrong? It seemed like just a little brake fluid was coming out slowly from the bleeder when I cracked it. Then it started making a leaking noise and I saw it flowing down the bottom of the tire on the back of the wheel. Why would the rubber pop out of a new cylinder?
 

Goldie Driver

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These are brand new wheel cylinders by the way. What did I do wrong? It seemed like just a little brake fluid was coming out slowly from the bleeder when I cracked it. Then it started making a leaking noise and I saw it flowing down the bottom of the tire on the back of the wheel. Why would the rubber pop out of a new cylinder?
Bad luck/POS chinesium part.

If the shoes are still dry you should be able to change the wheel cylinder out only removing 1 spring.:waytogo:
 

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