<VV> "Brake" Failures

[Sethracer@aol.com]

In a message dated 5/7/2004 6:51:52 AM Pacific Standard Time, 
khammett@stainlessfab.com writes:
Thanks Chuck for expanding on the Dual MC (actually MC failures).  The types
of failures that you point out are true but rare these days (I haven't had a
MC fail in many years now).  Neither one of us mentioned that if BOTH a
front and rear line fail you have no brakes!  Best to have a working
emergency brake as you point out and to have a well maintained brake system.

Once in a while the early vs. late Corvair controversy jumps up and everyone 
takes a few shots and has a few laughs. This one is serious. I believe the 
early model Corvair (at least the 62-64 models where kits are easily available, 
not sure of the 60-61s) should change to a dual master cylinder if any regular 
driving is planned. Why? - The swing axle on the rear of the early Corvair has 
proven to be a reliable performer for more than 40 years. And the 
U-joint/yoke/axle is a sufficient design for most driving conditions. Failure of that 
assembly, however - likely to be more common given the ages of the components - 
can cause a combination of events which might ask more of your braking system 
than it will be able to deliver. 
Since the axle/yoke is retained by a bolt, with a mild fit, they can fail. I 
have seen early models where failure of the yoke attachment (and not enough 
bearing press)causes the axle to move outward from the  body/chassis, taking the 
brake drum with it. The car will normally be slowing down pretty rapidly at 
that point. But, with a single master cylinder system, virtually all braking is 
gone - And I mean all systems. With the drum no longer on the shoes, all 
hydraulic pressure from the master will spread those unrestrained shoes and have 
no effect on the other three wheels. In addition, the drum departure removes 
any effect of the emergency brake system as well. Of course the offending side 
is open, but the balancing design of the Corvair, and virtually all other cars, 
means virtually no mechanical action on the other side either. You will have 
no brakes. A dual master cylinder installation will retain limited front brake 
capability, even under those circumstances. - Seth Emerson  (Please note, I 
don't sell brake systems and the 1965 up on jackstands in the driveway has a 
single master cylinder system. - But not for long.)