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bad secondary master cylinder?

4 posts Started 6 Apr 2012 Last recovered post 16 Jul 2012 Wayback Machine snapshot 13 Mar 2014

#1
So I've bled all the brake lines according to the FSM. I've rotated the left front caliper and tapped with screwdriver. I've zip-tied and waited. I've run more than a quart of new fluid through. When I bleed out the PCV with the pedal, no more air but I get squish sound up front and only one firm pump with the secondary master cylinder. Next few pumps with SMC are "empty". Wait a few minutes and one firm pump at SMC again.

At what point do I suspect the seals in the SMC?
#2
I have the same symptoms! Have you sorted out the problem yet?
#3
Yep. Finally got it. Jay-D did a really nice write up by the way. His was also the first thread I found (and I read dozens) that addressed my confusion about the Secondary Master Cylinder.

In a PM he explained: "Since the SMC doesn't have a reservoir, my helper would pump the pedal once and release, I would pump the SMC only once and not release until my helper pumped the pedal again which forcefully released the SMC. When I was figuring this all out, I would pump the SMC, then release, then pump again and release, but since new fluid wasn't entering in to the system via the rear pedal lever; air was coming back in to the lines."

Anyway, check out
http://www.vfrdiscus...__+brake +bleed
#4
Thanks skymon! I found the same write up from Jay-D and followed it to the T.
End of thread · 4 posts recovered Wayback Machine snapshot 13 Mar 2014