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Old 02-02-2013, 08:18 PM   #1
8door
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?? Bleeding and adjusting brakes with power brake canister.

Just installed a new master cylinder and new power brake canister.
Did a bench bleed on master before installing and cleaned all the lines
and installed new wheel cylinders.
Began the air bleeding lines and filling them with fluid. Starting with right rear
wheel my wife slowly pushed brake pedal while I opened and closed the bleed nut. Then moved to the left rear , after all air bubbles stopped there is not very much pedal.
I expect the pedal to be up and firm with just two rear wheels.
As this is is my first at bleeding a power brake system got other questions :
1.Do I need to start the engine and get vacuum to the canister while bleeding ?
2.Or can you feel some firmness in the pedal ?
3.How do I adjust the master cylinder push rod ?
Thanks guys
This is the one time I can direct my wife to do as I wish he he.
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Old 02-02-2013, 08:40 PM   #2
TBONE1964
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Re: ?? Bleeding and adjusting brakes with power brake canister.

Can you post a photo of the air bleeder you are using?

Did you bleed the front brakes? If you changed the master then you need to bleed the fronts as well.

Are the front brakes disc or drum?

You should not have to start the truck to bleed the brakes. It will not make any difference except for the muscles in your wife's thigh.

The master cylinder push rod should have a jam nut inside the cab over the steering column. You should be able to loosen the jam nut and turn the rod in the direction you need. There is rarely ever a reason to do this even when replacing the booster or master.
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Old 02-02-2013, 09:42 PM   #3
airdale94
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Re: ?? Bleeding and adjusting brakes with power brake canister.

You should bleed the master at the lines also, even after bench bleeding. Don't pump it just push down once and hold. Crack line loose. Start with the one closest to the firewall. Ideally you would have wanted to do this first. Then the rears. Then the fronts. You should have pedal now. Start it up and check pedal. Improperly adjusted shoes (not out far enough) can cause a low pedal. If after all this your pedal is still low. Then think about adjusting the master cyl. push rod.
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Old 02-03-2013, 12:57 AM   #4
8door
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Re: ?? Bleeding and adjusting brakes with power brake canister.

Quote:
Originally Posted by airdale94 View Post
You should bleed the master at the lines also, even after bench bleeding. Don't pump it just push down once and hold. Crack line loose. Start with the one closest to the firewall. Ideally you would have wanted to do this first. Then the rears. Then the fronts. You should have pedal now. Start it up and check pedal. Improperly adjusted shoes (not out far enough) can cause a low pedal. If after all this your pedal is still low. Then think about adjusting the master cyl. push rod.
Tbone and airdale
The truck is stock shoe brakes. All lines were cleaned and empty.I did only the rear first then checked and stopped to see if any pedal.
I intend to go through the procedure always starting with the furthest wheel from master LR RR RF LF.
Only using the fluid pumped from master cylinder. I have always bleed non power assisted brakes.
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Old 02-03-2013, 01:18 AM   #5
BarryB
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Re: ?? Bleeding and adjusting brakes with power brake canister.

If i read correctly, you still need to bleed the front brakes. If you replaced the master cylinder then all 4 corners need bled. Which would cause a soft pedal.
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Old 02-03-2013, 12:02 PM   #6
8door
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Re: ?? Bleeding and adjusting brakes with power brake canister.

Quote:
Originally Posted by BarryB View Post
If i read correctly, you still need to bleed the front brakes. If you replaced the master cylinder then all 4 corners need bled. Which would cause a soft pedal.
Yes, that will be done next.
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