Bus master cylinder replacement

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grandfatherjim
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Re: Bus master cylinder replacement

Post by grandfatherjim » Mon Sep 26, 2011 9:01 pm

Latest post of the previous page:

I imagine a combination of compressed air and liquid in there, with the bubble of air slowly moving within the brake line i.e. there isn't really fluid returning to the MC. Having said this, I don't know why the air would "want" to return to the MC. But several people have sworn it worked, FWIW.
Maybe gravity plays a part. It does explain most things we can't otherwise understand.

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Amskeptic
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Re: Bus master cylinder replacement

Post by Amskeptic » Tue Sep 27, 2011 7:23 am

grandfatherjim wrote:I imagine a combination of compressed air and liquid in there, with the bubble of air slowly moving within the brake line i.e. there isn't really fluid returning to the MC. Having said this, I don't know why the air would "want" to return to the MC. But several people have sworn it worked, FWIW.
Maybe gravity plays a part. It does explain most things we can't otherwise understand.
Having never had an issue bleeding brakes in my life ... I do not carry a 2x4 around to jam the pedal.
Colin
BobD - 1978 Bus . . . . . . . . . . .111,130 miles
Chloe - 1970 bus . . . . . . . . . . . 206,787 miles
Naranja - 1977 Westfalia . . . . . 81,366 miles
Pluck - 1973 Squareback . . . . . 55,510 miles
Alexus - 1991 Lexus LS400 . . . 72,113 miles

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dtrumbo
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Re: Bus master cylinder replacement

Post by dtrumbo » Tue Sep 27, 2011 9:30 am

How does the air get out of the master cylinder once it has spawned to that point?
- Dick

1970 Transporter. 2015cc, dual Weber IDF 40's
1978 Riviera Camper. Bone stock GE 2.0L F.I.
1979 Super Beetle convertible.

... as it turns out, it was the coil!

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Amskeptic
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Re: Bus master cylinder replacement

Post by Amskeptic » Tue Sep 27, 2011 4:14 pm

dtrumbo wrote:How does the air get out of the master cylinder once it has spawned to that point?
When you release the pedal, air bubbles that have migrated to the master cylinder and successfully negotiated the bend from the line to the compensating ports will bubble up to the reservoir.
Colin
BobD - 1978 Bus . . . . . . . . . . .111,130 miles
Chloe - 1970 bus . . . . . . . . . . . 206,787 miles
Naranja - 1977 Westfalia . . . . . 81,366 miles
Pluck - 1973 Squareback . . . . . 55,510 miles
Alexus - 1991 Lexus LS400 . . . 72,113 miles

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