[DeTomaso] Poor brakes

forestg at att.net forestg at att.net
Fri Jul 10 10:26:16 EDT 2009


 To clarify; the shuttle valve does not indicate pad wear. It's purpose is to alert you if you lose pressure to one side such as would happen if a line broke or a caliper seal leaks.
  -------------- Original message from JDeRyke at aol.com: --------------


> In a message dated 7/9/09 5:35:36 PM, wdemelo at cogeco.ca writes:
> 
> > It feels like I'm driving a '65 Ford with drum brakes. Every so often 
> > they work (1 in 20 attempts), otherwise I've got to really step on the pedal. 
> > I don't think my booster is working. How do I test it?
> > 
> Pull and plug the vacuum hose at either end and try them. There should be a 
> difference in stopping power. Also, if they're working, there will be an 
> audible 'hiss' when you step on the pedal or let it off. The true test though 
> is to add a 0-1500 psi gauge to each circuit and check the pressures. 
> Without a proportioning valve, you'll be hard-pressed to get 350 psi with the 
> engine off, but you should see 1200 psi with the engine on and vacuum at the 
> booster. I've found several Panteras in which the vacuum line was disconnected 
> for some odd reason....
> The shuttle valve under the booster often sticks in internal varnish at one 
> end or the other of its travel, and it will not reset itself; the only fix 
> is to take it completely out, remove the end fittings and tap the shuttle 
> back into the valve center with a nail-set, then   replace and carefully 
> re-bleed the whole system. With the shuttle stuck, you essentally LOSE the 
> brakes 
> at that end of the car, which makes for p-poor stopping power. The shuttle 
> can be safely thrown away and the various lines hooked together. Its only 
> job is to warn you of worn brake pads, and only if you still have pads with 
> ground wires embedded. 
> Finally, if you also throw away the stock non-adjustable proportioning 
> valve, ALL the brakes will run at full power rather than having the fronts 
> hamstrung as they are stock. Deleting the prop-valve and the shuttle valve are 
> often the only brake upgrade most street Panteras need. And its pretty low 
> cost. Good luck- J Deryke
> 
> 
> **************
> Dell Studio XPS Desktop: Save up to $400 
> - Limited Time Offer 
> (http://pr.atwola.com/promoclk/100126575x1222466512x1201463496/aol?redir=http:%2
> F%2Faltfarm.mediaplex.com%2Fad%2Fck%2F12309%2D81939
> %2D1629%2D3)
> _______________________________________________
> 
> Detomaso Forum Managed by POCA
> 
> Archive Search Engine Now Available at http://www.realbig.com/detomaso/
> 
> DeTomaso mailing list
> DeTomaso at list.realbig.com
> http://list.realbig.com/mailman/listinfo/detomaso



More information about the DeTomaso mailing list