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 has found most to be quite good for Street and Light Track uses. Best results are found with good quality, fresh DOT-3 or DOT-4 fluids. We recommend the use of silicone DOT-5 Silicone fluid only for show cars that will not see normal use. DOT-3 and DOT-4 are available at your local parts supplier. For racing, Baer recommends and uses only Castrol SRF. Baer stocks and sells 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).
- 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:
- 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.
- Repeat the BLEEDING SEQUENCE (never stroke the pedal more than one time) until all signs of air are purged (no bubbles) from fluid.
- IMPORTANT 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.
- 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.
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.
If any of this is unclear, or you have comments, please call the us at (602) 233-1411