Friday, April 20, 2018

LOSE YOUR PEDAL DURING RACE Fluid boiling due to wet fluid or foot drag. Flush out entire system with fresh Wilwood Hi-Temp° 570 racing brake fluid. Install dashboard brake light reminder.
Undersize brake system. Refer to the caliper web page to select the correct caliper/rotor combination for your application.
Wrong size residual pressure valve. Use no larger than 2 lb residual pressure valve.
Incorrect or faulty master cylinder. Repair or replace master cylinder.
Leak in caliper or hydraulic lines. Check for leaks in caliper and lines.
Inadequate ducting. Reposition air ducts to center of rotor and caliper. (refer to Wilwood air duct technical sheet)
Pedal linkage failure. Check pedal assembly.
Excessive spindle deflection in corners. Check spindles for warpage. Install 2 lb residual pressure valve.
BRAKE DRAG Bad master cylinder. Switch or replace master cylinder.
Incorrect residual pressure valve. Use no larger than 2 lb residual pressure valve.
Rotors warped. Replace rotors.
Calipers not square to rotor. Re-align brackets or shim calipers.
Tapered brake pads. Replace pads, check caliper alignment to rotor.
M/C has internal residual pressure. Remove residual pressure valve.
CAR WILL NOT STOP Glazed pads and/or rotors. Grind and/or sand glaze from rotors.
HAVE TO PUSH TOO HARD ON PEDAL Too large of a master cylinder. See master cylinder web page to select the correct size unit for your application.
Not enough pedal ratio. Increase pedal ratio, see pedal technical tips.
Pedal mounted at bad angle. Master cylinder push rod should not be off more than 5° in any angle
Wrong pad material for your applications. Pads must match rotor operating temperature range. See brake pad web page.
Frozen pistons in calipers. Rebuild calipers.
CALIPER LEAKS Caliper seal old or dried out. Replace with new seals.
Nick or ding on piston or cut seal. Replace pistons and/or seals as necessary.
SPONGY PEDAL OR BOTTOMS OUT Air in brake system. Re-bleed the system.
Calipers not bled with bleed screws straight up. Unbolt calipers and hold with bleed screws in the vertical position.
Wrong size master cylinder (too small). Refer to master cylinder web page to select the correct size for your application.
Faulty master cylinder. Replace master cylinder.
Calipers not mounted square to the rotor. Re-align brackets parallel to rotor, or shim caliper.
Calipers mounted equal to, or higher than master cylinder. Install 2 pound in-line residual pressure valve.
Calipers flex excessively. Check pressure. Do not exceed 1,200 P.S.I.
Pedal ratio too great. Reduce pedal ratio.
Excessive spindle deflection in corners causing piston knock-back. Install 2 pound in-line residual pressure valve. Check spindles for warpage.
OSCILLATION FEED BACK IN PEDAL Excessive rotor run out. Shim between rotor and hub/hat.
Pad material buildup on rotors. Change pads, clean rotor face.
Calipers loose. Tighten caliper mounting bolts.
Rotor faces not parallel. Re-grind rotor faces, or replace rotors.
Cracked rotors. Replace rotors.
Excessive front bearing clearance. Check for proper bearing size, or tighten the spindle nut.
Didn't see the answer to your question?
Call Wilwood Technical Support; we're glad to help.
Phone: (805) 388-1188
Email: Sales/Tech Support