Re: [T2] Those bleedin' brakes, Pt II

["George Lyle" <glyle@xxxxxxxxxxxxx>]

> Hi list - thanks for the bleedin' help so far...
> 
> Part II
> When I mentioned that my method of bleeding yielded trouble free results at 
> the back two wheels, BUT big and small bubbles at the front two wheels, Some 
> of you suggested that the master cylinder might be gone.
> How do I know for sure? Is there a simple in-place test?
> 
> There was one suggestion that since the bleeders are high up at the back, 
> but low to the road at the front that I may have raise the wheel off the 
> ground, or lower the catchment vessel to BELOW the bleeder?
> (I dropped Physics 11, although this seems like a Science 8 question)

A poor decision on your part!  :)

The brake fluid is relatively viscous and the lines rather narrow, 
so bubbles tend to be pushed along the line even if the line goes 
slightly downhill.  Once in the brake cylinders, they tend to rise 
to the top.  I usually put the catch bottle on the ground and use 
thin clear plastic hose (fish tank tubing) to go to the catch bottle.  
The bubbles will slowly rise in this tubing, but slowly enough that 
they will be pushed out the end by the next push.

> And for some reason, I thought that the brake system was split diagonally, 
> not front/back, for safety reasons. True?

Not on aircooled VWs.  I think that the first rabbits (golfs) had diagonal brakes.

George Lyle