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Ever since I installed Wilwood FSLI calipers on the front of my car my pedal has been inconsistent like there's air trapped in the system somewhere. I have bled every bleeder on them and am getting solid fluid with no bubbles. I have replaced the master cylinder and bench bled it. Every rubber line on the car has been replaced. There are no leaks anywhere. I attempted to use a Motive power bleeder on it but can't get the thing to seal up.
Last night I jacked the back end up as high as I could get it, and I tried to bleed it out again. Again, just getting solid fluid.
I even tried to crack the lines at the master cylinder and re-bleed the master.
Took it out for a drive and had a pedal although not the best. After a couple stops, it was going almost to the floor again.
Guys I'm stumped. Air trapped in the proportioning valve maybe?
Last edited by Anti-Venom; 05-17-2023 at 07:44 AM.
Do you have the brake lines fitted to the top side of the caliper? Being placed too low on caliper would keep air trapped inside.
Lines are ran to the "middle." (edit)
Originally Posted by ShiftyCapone
What booster and master cylinder are you running? Are you alternating the bleed on the front? Fixed calipers with two bleeders are a pain to bleed.
I'm running the stock booster and master. I've alternated from the inner to the outer bleeders and have bled both driver and passenger several times. I'm getting no air out at all.
Last edited by Anti-Venom; 05-17-2023 at 08:04 AM.
Not easy to see based on the angle of that one picture and the distance from the caliper, but is that a bleeder at the bottom of the caliper or a crossover tube? It kind of looks like all bleeders.
It also looks like the brake line is connected to the top of the rear of the caliper. I'd think there should be a hole in the center of the rear of the caliper for the brake line connection.
Not easy to see based on the angle of that one picture and the distance from the caliper, but is that a bleeder at the bottom of the caliper or a crossover tube? It kind of looks like all bleeders.
I didn't see this at first but LA is correct. You should have a cross over tube on the bottom side of each caliper.
These are the newer FSLI calipers with the internal crossovers, and the brake line enters the caliper in the center. They're designed where they can be mounted in either a leading or a trailing position. The older style Wilwood's had the external crossover tube and had to be mounted in a certain orientation.
I went out and attempted the pressure bleeder again last night. This time with c-clamps on the plate. The end result was once again another quart of brake fluid down my strut tower and all over my garage floor. I've used them with screw on caps and they work great, but for this type of master cylinder, the pressure bleeder was a complete waste of money.
Last edited by Anti-Venom; 05-17-2023 at 08:14 AM.
I have wilwoods front and rear. Fronts are 6 piston and rears are 4 pistons so they're not the exact same calipers but like yours, 4 bleeders, line in the center and no crossover tubes. I put a wilwood prop valve in and a new master (stock replacement) and all new lines. Initially I filled the system used a vacuum bleeder and started pulling the fluid. It took a lot! Getting a seal on the bleeder screws with the vacuum pump was a pain. There was tons of air. Initially driving the car I had to pump up the brakes to get pressure. I went back and bleed them more w the vacuum bleeder and then went old school and had my wife push the brake pedal and I finished bleeding them that way. I used a rubber hammer to tap the calipers to help move any trapped air. Probably went through 3 quarts of brake fluid w only a little spillage. I'd check your prop valve or replace it w a wilwood one. It doesn't have the safety valve to mess things up. When in doubt, bleed more!
05-16-2023, 08:36 AM
I've used them with screw on caps and they work great, but for this type of master cylinder, the pressure bleeder was a complete waste of money.
