Brake question

[gfarn1]

Hello Mighty Samba Gurus,

I cannot get pressure to build up on the brake pedal. Here's what I have done so far:

1. Replaced all the cylinders, shoes, lines, and master cylinder.
2. Adjusted brass star things just below where they start to rub the drum.
3. Bleed the brakes (several times now)
4. Confirmed master cylinder rod is in correct position

What have I missed?

Thank you in advance!

Greg

[Eric&Barb]

Single or dual circuit??
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[gfarn1]

Single

[KevinAlbrecht]

Are you still getting bubbles on the last bleed?
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Kevin Albrecht
1963 Panel


Don't forget those seat-belts!
My '66 after the crash.
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[gfarn1]

[flemcadiddlehopper]

Did you bench bleed the master cylinder before you put it in?

If not, start there. Then, have someone pump the pedal for you and open the closest bleeder screw to the master. Now put your finger over the bleeder. When you tell the helper to push the pedal (one full stroke) you lift your finger. When the pedal reaches the floor your helper says "floor" and you then cap the bleeder with your finger. Keep doing this until you get a good solid flow from the bleeder, then close it properly and move to the next bleeder. Keep an eye on the brake fluid feel in the master.

Once you have done all four and you are now furthest away from the master, have your helper then pump up the pedal ( should be able to build pressure ) then hold the pressure for you to "pop bleed" each wheel cylinder. Use a clear hose on the bleeder that leads up before dipping down ( like a question mark ) so you can watch for air in the line. Pop bleed each one working your way back to the closest one to the master.

This will take a large volume of brake fluid to do properly, unless you have access to a pressure bleeder.

Hope this helps.

Gordo.
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Everybody Dies....Some Never Live.

Retrograde Garage. Vintage Aircooled, and others.

[Bruce Amacker]

You don't need to bench bleed the master before installing it. If you're not using one already, buy a vacuum pump style bleeder kit (HF, $25) and use that to apply vacuum to each bleeder screw. They work great, no mess, no fuss. Lock your adjusters all the way tight so the drums won't turn, that way you know when the air is gone, your brake pedal will be high and hard. Then loosen the adjusters to the proper adjustment.

Good Luck!
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'66 Deluxe Bus
'65 Standard Bus
Build threads:
'66- http://www.leakoil.net/forum/viewtopic.php?f=23&t=2888&sid=54d8dedfb3822f99c7f2ea430cb4e856
'65- http://leakoil.net/forum/viewtopic.php?f=23&t=4263

[fotoroadie]

I suffered this same issue - no amount of human help bleeding or vacuum style pump bleeding would work then I ordered this from Summit Racing & bingo worked first time out of the box & a one man job.

[Abscate]

Get those shoes hard against the drums before you bleed. Just touching back is too loose. Turn the adjusters until they stick hard, then back off 2-3 clicks.

This is easy if you have cleaned up the adjusters shiny metal, greased them up, etc.

I've never bench Bled a master cylinder in my life. I usually bleed solo with the system under no pressure, just getting fluid through the lines and calipers with a Tygon tube looped up
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[BarryL]

[flemcadiddlehopper]

Vacuum bleeders work very well on disk brake systems.

On drum systems, the vacuum can pull air past the wheel cylinder cups when too much vacuum is used. Also, air is pulled in around the bleeder screw threads of the bleeder that is opened and can be deceiving. Proper care and attention can result in a perfect bleed with them. But in the end, to be sure there is no air in the system.



Gordo.
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Everybody Dies....Some Never Live.

Retrograde Garage. Vintage Aircooled, and others.

[gfarn1]

Thanks everyone for the tips!! Huge help!! I'll try a bit from all of your messages and get back to you what worked. Wish me luck!

Thanks again!!
Greg

[Eric&Barb]

Looking forward to any updates!
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[Help Help]

+1 on the power bleeder. Tried the vacuum pump method and swear by the power bleeder.