I tried drilling and tapping to an oversize screw but
it still weeps badly.
A common misconception is that the threads of hydraulic fittings are
what provide the seal. In case of tapered pipe threads, this is the
case, but for most high pressure hydraulic systems you'll find that
the threads only purpose is to supply the clamping force needed by
whatever does provide the seal, in this case the taper on the end
of the bleeder screw fitting into a matching taper in the caliper body.
Don't worry, all is not lost. A well-stocked auto parts store, like a
NAPA or maybe a Pep Boys, may have just the ticket. Somewhere they likely
have a rack with varius bits of fittings, and may have a selection of
bleeder screws in a couple of different lengths and diameters. Most will
be 3/8 or 7/16 SAE threads. Use anti-sieze.
I thought I had the supplier and part number of another item that may be
handy, a bleeder screw repair kit. Don't worry, you aren't the first to
do this. Basically it is a special bushing with 1/8 pipe threads on the
outer diameter, and a small brass bleeder screw in the center. You drill
out the stripped bleeder, tap for 1/8 pipe threads (what was it I said
a moment ago?) and pop this puppy in. This was the little item I used to
finish off the remote clutch bleeder in the Killer Spit.
A bit of anti-sieze and judicious tightening will go a long way towards
preventing such problems. This is another area, like rocker covers and
oil pans, where "if tight is good, tighter must be better" just does not
apply.
mjb.
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