[Orange Crush 1LE]

Guys,

I recently dropped in a new 416 and added a brake pressure sensor, and car has a fresh full flush with Motul 600. Now my clutch goes to the floor after a couple of hot laps at the road course. When the car cools, it goes away. Hoping it's just air in the clutch line, I used the method described in the factory service manual to pull air out of the system. This is not a typical bleed procedure, everything is done at the reservoir cap. See details in the photo of the service manual, but in summary:

1. Fill reservoir
2. Attach a Mityvac metal vacuum pump (this is a hand-held pump) to the reservoir using a cap bleeder adapter (just a reservoir cap with a fitting on it for the vacuum hose).
3. Pull 15 - 20 in Hg vacuum, which will pull any air out of the clutch fluid line.
4. Release vacuum, and refill brake fluid as necessary.
5. Repeat steps 3 and 4 until the fluid level is full and no longer drops and air bubbles can no longer be seen in the reservoir.

I went to the auto parts store and bought a Mityvac and hooked it up to my reservoir using a cap bleeder adapter that came with my brake bleeder.

I had strange results: Although the fluid level didn't drop, which suggests that there were no bubbles, it did pull a couple of inches of fluid out of the reservoir. Is this normal / expected? You would think that the method in the factory service manual would be flawless, and would not pull fluid up unless there's something wrong with the system. But maybe it sucked my brake pistons in, as evidenced by the soft brake pedal which required pumping after this procedure. I wonder if something is wrong with my master or slave cylinder, or something else?

I took it for a test drive and the problem didn't surface, but I didn't have an opportunity to get on it at all, and so the problem still may be there when driven hard and things get hot.

Any thoughts? Anyone else use this method?