Hi, I was flushing the brake fluid by using the power bleeder today. And things never went as smoothed. Need to pick the brain of fellow fchatters. I replaced the fluid in the reservoir (both side) with fresh one. hooked up the power bleeder filled with brake fluid to the left side of the reservoir, right side has cap on. Pumped the bottle to 15psi. Cracked the bleeder at the rear right caliper. Only a little bit of brake fluid came out. Then nothing. The pressure on the bottle was not dropping. I tried hooking up the Power bleeder to either side on the reservoir. it was the same. Pressure wasn't dropping. I've done the power bleeding many times with my other cars without any trouble. Is the 456gt brake system different than other cars? Is there a specific procedure to enable the fluid to flow?
The 456 GT with Teves system has hydraulic boost instead of pneumatic boost, but not sure how that affects bleeding. Looking at the WSM, you may need to have the ignition on to power the hydraulic boost system or it may block fluid movement. Somebody here should know the answer, since mine is not based on experience and I may be misreading it.
I finally got the fluid to flow. Clutch and brakes are all done on the pass side of the reservoir. Just where is the min line for clutch bleeding? I was having my wife pumping the clutch for me. I was sure the reservoir was still 90% full. Then it just sucked in all the air. I ended up doing another round of power bleeding, and a round of reverse bleeding. There's no more bubbles as far as I can tell. I let a whole liter of fluid to flow thru the system. But the clutch pedal is still feeling funny. Not as firm as before.
Played with the clutch more this afternoon. It has pressure. but very low on the flow. the first half felt sponge. I think there's still air trapped in the master cylinder. Is there a way to bleed the master cylinder? There's no Bleeding screw. Only the inlet hose from Reservoir, and outlet hose to the slave cylinder.
Putting a closure to this. I used reverse bleeding method to clear the air in the clutch master cylinder. Did it very slowly. Finally got a hard pedal. Another maintenance item in the bag. Moving on to the windows adjustment next.
