6t9 stang

not sure what the deal is. just got done puttin my T5 in and started it for the first time. With the car off the brake pedal is normal stiffness, but as soon as I start the car the pedal gets really squishy? I installed a diff. vacuum booster thats the only the that has changed in the brake Sys.

could really use some help, I would love to drive the car before the end of the day.

ninteen66mustang

Are you saying you just installed power brakes? That is what power brakes do, they make the pedal easier to push. If you have a newer car go turn it on and press the brakes, then turn it off and press the brakes a few more times. The pedal will get much harder to push after the first few pumps. not sure if that is what you are talking about, but it sounds normal to me.

racin66coupe

^+1 couldnt've said it better

JMD

As long as the pedal does not go to the floor or very close to the floor everthing should be Cool and the Gang...

6t9 stang

no thats the thing, I had power brakes before I did the T5 swap... I just CHANGED boosters becuase I needed the more compact one to work with my clutch cable... And yes the pedal goes to the floor..My dad did not bench bleed the master cylinder could this have anything to do with it.

Gun Jam

that has everything to do with it

the air left in the MC is now in the brake lines

4reboy

yeah I didn't bench bleed my master cylinder and it did that of course. What I did was take out the brake lines and screw in this plastic bolt type thing with a nub for a plastic tube. then put these tubes in the reservoir and pump the brake pedal a crap load until the bubbles go away. This is pretty much the same thing as bench bleeding, just while its in the car.

from there connect the brake lines and bleed all the brakes and it should be back to normal.

rmodel65

yeah you need bench bleed it out then bleed the rest of the system like this
Bleeding the brakes requires a properly sized box wrench for the bleeder and the clear plastic bleed hose provided with your system. Good quality, non-silicone fluid is also a must. Baer Brakes has tested a wide variety of fluids and strongly recommends Performance Friction’s Z-Rated fluid #90016 for street and occasional track use (with Motorcraft PM1 our backup suggestion for this same duty). These two have been proven to be more effective than fluids that are often many times more expensive. For racing, Baer recommends and uses only Castrol SRF. Baer stocks and sells both the Performance Friction Z-Rated and Castrol SRF. Always remember, good to excellent brakes or fluid do not function without adequate cooling. In fact, the more serious your brake system, the more attention that needs to be directed to proper ducting, as they will generate more heat due to increased capacity. BLEEDING BRAKES IS NOT DONE WITH PRESSURE, IT IS PURELY A FUNCTION OF MOVING FLUID THROUGH THE SYSTEM. THE OBJECT IS TO DISPLACE AIR, NOT TO SEE HOW FAR FLUID CAN BE SHOT OUT OF THE CALIPER!
Proper Bleeding Technique Enlist someone who will help you bleed the brakes. Make sure they also read these instructions carefully (so they understand the goal). [ol][*]For systems which are essentially dry front and rear, start by filling the master cylinder with proper fluid. Pour slowly so as not to aerate the fluid.[*]Next, move to the first caliper, attach the clear plastic bleed hose to the bleeder and open it. Hold the hose upright so that you can monitor the escape of air bubbles. VERY SLOWLY stroke the brake pedal by hand or foot until fluid comes out. Now close the bleeder.[*]ACTUAL BLEEDING SEQUENCE: [ul][*]Have your partner very slowly, with modest pressure (approximately 25-30 lbs.ft.), stroke the pedal ONE TIME until hydraulic resistance is encountered. Ask your partner to hold at this point with the same modest and even pressure and notify you that he is “holding.”[*]Open the bleeder, letting the pedal go to the floor or until it stops, using the same modest level of pressure, then close the bleeder again. Notify your partner “the system is sealed.” He can then slowly release pedal pressure.[/ul][*]Repeat the BLEEDING SEQUENCE (never stroke the pedal more than one time) until all signs of air are purged (no bubbles) from fluid. IMPORTANT [ul][*]NOTE: DO NOT LET THE MASTER CYLINDER RUN DRY! Be sure to check the fluid level after every third bleeding sequence or sooner if reservoir volume is very small.[/ul][*]Before moving to the next caliper, take a small block of wood or a plastic hammer and carefully tap the caliper to dislodge any additional air bubbles that may be trapped. Then bleed one last time.[*]Move to the next caliper and repeat the procedures previously outlined. Continue until all calipers have been bled. Before re-installing wheels and placing the car on the ground, we recommend you carefully wipe clean all caliper surfaces, hose joints and fittings, making sure they are all dry and free from seepage. If not, inspect and tighten appropriately. Spray all rotor surfaces with Brake Kleen® or a similar product to remove all dirt and oils from your hands that may have been transferred to the rotor during assembly. Also remember to remove the nut that has been holding rotor in place before attempting to re-install the wheel.[/ol] For street use, as with any time you open the brake system, it may be advisable to repeat the bleeding procedure after driving the vehicle for a day, as driving the car may dislodge some additional air bubbles. For competition cars, we recommend repeating this procedure directly after at least the first two sessions the car is on track and at the beginning of each race weekend thereafter. Even if your pedal is high and firm and additional bleeding is deemed unnecessary, always inspect the calipers, hoses and fittings after the first outing for signs of any fluid seepage and correct immediately.

kalli

short story: if the pedal goes to metal then DO NOT DRIVE THIS CAR until it's fixed

67t5ponycoupe

You don't have to pull it off the car. Just bleed it at the master cylinder with it still on the car and bleed it at the wheels. It will be fine.