MC Brake Push Rod "Notchy Feel"

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Craig Geiger
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MC Brake Push Rod "Notchy Feel"

#1 Post by Craig Geiger »

I replaced the master cylinder on my 63 T6 B car - same MC, just direct replacement (single circuit). Brakes bled, pedal pressure is fine, brakes work correctly. However, the pedal has always felt a bit "notchy" at first engagement and pressure. Meaning, if you step on the brake pedal, it begins engaging, and then you can feel a "notch" and then it re-engages again as you continue with more pressure. It definitely isn't dramatic, and does not seem to have any impact on braking performance, but bugs the crap out of me. I followed the factory procedure for reinstalling the mc and then adjusting the clearance of the push rod to the piston. The adjustment didn't seem to make any difference. It "feels" almost like maybe the push rod is first engaging at an angle, and then seats itself as pressure increases. But I have no idea... I was going to try to disconnect the push rod from the pedal and see if I could figure out anything from there. Anyone have any suggestions on troubleshooting or similar experiences?
1963 356B T6

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Phil Planck
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Re: MC Brake Push Rod "Notchy Feel"

#2 Post by Phil Planck »

Maybe pressure switch has air in it.
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George Hussey
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Re: MC Brake Push Rod "Notchy Feel"

#3 Post by George Hussey »

good call, remove the wooden pedal board and watch the action of the engagement rod and the pedal cluster. You could even have a worn pedal cluster and therefore something rubbing or interfereing
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Jim Liberty
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Re: MC Brake Push Rod "Notchy Feel"

#4 Post by Jim Liberty »

George is right on. Sounds like a mechanical problem. Have someone press the pedal slowly while you watch the system working, up close. .............Jim.
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Martin Benade
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Re: MC Brake Push Rod "Notchy Feel"

#5 Post by Martin Benade »

Yes, easy if it’s the pushrod pivot, harder if it’s the main pedal bushing.
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Jim Liberty
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Re: MC Brake Push Rod "Notchy Feel"

#6 Post by Jim Liberty »

I've had the pivot stick which leads to a broken cable. Could be that Craig. ............Jim.
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Martin Benade
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Re: MC Brake Push Rod "Notchy Feel"

#7 Post by Martin Benade »

Jim I think that was a clutch problem you had, not a brake pushrod problem.
Cleveland Ohio
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56 VW
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Jim Liberty
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Re: MC Brake Push Rod "Notchy Feel"

#8 Post by Jim Liberty »

Martin, you are correct. I just has another birthday, and it has not made my brain any better. ..........Jiml
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Mike Wilson
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Re: MC Brake Push Rod "Notchy Feel"

#9 Post by Mike Wilson »

What happened to "with age comes wisdom"! 😜

Mike
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Martin Benade
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Re: MC Brake Push Rod "Notchy Feel"

#10 Post by Martin Benade »

Jim don’t worry. You’re doing fine.
Cleveland Ohio
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Mike Wilson
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Re: MC Brake Push Rod "Notchy Feel"

#11 Post by Mike Wilson »

+1 !

Mike
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'63 B coupe

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