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I finished bleeding the brake system. A couple of the bleeder screws are still leeking no matter how much I tighten them. I tried changing bleeder screws with some extras I have, but it didn't help. I've tightened them down as much as I think I can without worrying about stripping them. These are new(rebuilt, original) calipers. I tried teflon tape but it didn't help.
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Re: '67 BRAKE CALIPER BLEEDER SCREWS
Rob,
I had this same problem with new bleeder screws. I kept tightening, loosening, retightening, testing until the leaking stopped. I think it's the two steel (metal to metal)surfaces finally mating on the entire circumference. It is nerve wracking, but everything's been OK with this since 1999. -
Re: '67 BRAKE CALIPER BLEEDER SCREWS
John and Rob-----
That's what it is. The bleeder valves are steel and the caliper housings are cast iron. After repeated "hogging down" of the bleeder screws, the bleeder SEATS become worn or distorted. Some rebuilders lightly "spot-face" the bleeder seats which are machined directly into the cast iron substrate material of the caliper half. The "seal" for the bleeder valve occurs at the interface between the bleeder screw and the seat in the caliper half. This "seal" has to be perfect to seal against the sort of pressures developed in hydraulic braking systems. The addition of teflon tape or any other type of sealant on the threads of the bleeder screws is an ABSOLUTELY FUTILE effort; no seal is created at the threads, anyway.In Appreciation of John HinckleyComment
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Re: '67 BRAKE CALIPER BLEEDER SCREWS
Joe,
My bleeder screws may be stainless. Does that add to the problem, because I have some steel ones I could replace them with...Comment
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Re: '67 BRAKE CALIPER BLEEDER SCREWS
Rob-----
It MAY have added to the problem of distorting/wearing the seats. However, changing them now will likely do no good.In Appreciation of John HinckleyComment
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