Thread: thems the brakes!

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o.k. i've got too much cam, too many carbs, and the 29'er is a little overwieght at 3400 lbs.
the brakes are good,however after the second or third stop braking seems to be very heavy! would a on board vacuum pump be a good cure? i know
somebody is going to suggest a vacuum can,but i feel this is kind of a stop gap means of fixing the problem!
i've bled the brakes,both on the bench and on the car.
the booster is under the floor(drivers side) and seams to hold vacuum for two
or three min.
i plugged a vacuum guage into the line going to the booster and it shows
18" at idle....hoses are new and tight,none of them have gone soft..
this ones got me talking to my dog!

in city driving is where i seem to run out of brakes,its a pretty small vacuum booster(ford style) pretty tight under there!
i'll take a look at the check valve,it might be something i've overlooked.
before i spend $300.00 on a pump maybe the smart thing to do would be
to slam in a vacuum can & see if that helps?
after all i could always sell it at a swap meet in the spring!

Do you have residual pressure valves in the brake lines?

i can find the proportioning valve, the block where the front and rear lines
join together(with the switch for the brake lites)
pardon my ignorance,what and where would i find the residual pressure valves?
seems i can't see the forrest for the trees!

since your brakes are below the floorboard, you should have residual pressure valves in both lines. 2 psig for disk brakes, 10 psig for drums.

http://www.streetrodstuff.com/Products/1651/

Unless they're built in to you proportioning valve block or master cylinder, you should have these for an under-floor master.

I'm not sure that will solve your particular problem, but everyone recommends them in your application.

i don't see any ov these residual valves anywhere on my machine!
will order a set and then start over
i never gave much thought as to how the brakes were set up!
shame on me!
will let you guys know in a while how i make out, thanx for the info guys!

If the brakes are good on the first hit, it isn't a residual pressure thing. Sounds like the engine vacuum isn't replenishing the booster fast enough, a can will fix it , or a cam change!