Falcopilot

I installed a CSRP power disc kit in my '68 Coupe. I now have the engine running and need to finally drive the car. The problem is the brakes......I've bled them..........have a good pedal.........but when I crank the car the pedal goes to ZERO!!! No resistance!! As most of you know I installed a 92 EFI 5.0 and AOD........I have the vacuum for the booster running directly off a port on the upper intake. What the heck is going on??? Is it possible there is to MUCH vacuum??? I am NOT a mechanic..........but have done all of this conversion on my own.....so I don't exactly know how the vacuum works.

Anyone got any ideas?

67mustang302

When cranking? It's possible there could be a vacuum pulling the pedal....but usually under cranking the intake is close to atmospheric.

Once the car is running is the pedal really soft? Do the brakes work? It could be an overly powerful booster for the setup.

Falcopilot

While running. There IS no pedal once it cranks.......like it's not even attached to the car!!

67mustang302

Did you pressure bleed then? Did you bench bleed the MC?

Falcopilot

Yes and yes.

I'm convinced it's a vacuum issue.......I'm gonna start changing some of the vacuum setup and see what happens.

dawson1112

You still have air in the lines some place,

I bet if you start the car and put it in neutral you can still push the car. Meaning no brakes. If the vacuum was pulling to hard on the booster it would engage the brakes and the car wouldn't move at all.

Boogie's_AutoRama

How are you bleeding the brakes?

The shade tree method of using a helper to open the bleeder while you hold the pedal down is iffy at best.

Better to use a piece of hose on the bleeder barb with the other end in a cup of brake fluid.
Plus, it makes it a one men job.






.

Falcopilot

Thanks!! Looks like more bleeding tonight then!

Falcopilot

I AM a shadetree, LOL!! More details on your method please?

dawson1112

IF you take a jar like a mason jar and fill it with brake fluid , you can open the bleeder on the wheel and use a small leangth of ruber tubing to fit over the bleeder then stick the other end in the jar pumping the brakes slowly , this will push air out while keeping the other end in fluid when you release the brake pedal it should suck fluid instead of air,

I recommend you use this , it is so much easier.
http://www.autozone.com/autozone/acc...er=601274_0_0_

Or if you want to to do the jar method you can use this

http://www.autozone.com/autozone/acc...ier=46839_0_0_