Brake bleeding

[Curt Cleavinger <rcleavin@domain.elided>]

I know this has been discussed before, but I didn't see it in the FAQ

I know the little button on the master cylinder should be depressed
at some point during bleeding, but when? The whole time? Just at first?
Anyone know what it really does? Second, I got some of the Russell 
bleeder screws (with the check valve in them), and I'm getting a LOT 
of brake fluid seeping past the threads of the bleeder screws, even
when they're only open 1/4 turn - can anyone think of a reason not
to put some rtv silicone on the threads? I've bled the brakes on the
Scout and Travelall at least 3 times without problems, and for 
some reason I'm having terrible troubles getting all the air out
(even with the Russell bleeder screws) - I'm starting on my 4th
gallon of brake fluid. Does anyone have any secrets they'd like to 
share? The only thing different this time is the rear disk brakes
(with the Eldorado calipers) - anyone with the TSM rear disks have
trouble getting them bled?

Thanks,
 Curt
   rcleavin@domain.elided  San Diego, CA
   Binder Bunch: http://www.off-road.com/~jweed/binder.htm
   Scouts West: http://www.scoutswest.com
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