Brake bleed and fluid question

[texasboy21]

My GT PP with Brembos has just under 6K miles, and is 6 months old. I have done a handful of track days the the pads have lost their initial bite - and I suspect it may be due to the fluid.

To remedy this I plan on flushing the fluid using a Motive power bleeder, and moving to Motul RBF600 fluid.

Couple questions:

1) Is it normal for the stock pads to loose their initial bite so quickly?
2) What pressure is recommended for the power bleeder?
3) Does the clutch line share the same fluid/reservoir as the brakes?
4) What order should the brakes be bleed?

Thanks!

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[jasonstang]

1. Maybe they have been heated and cooled so many times it has gassed out leaving the material very hard lack of grab?
2. Never used one.
3. Yes, it's shared via the black hose on the side of the reservoir.
4. From far to close to the brake reservoir so passenger rear, driver rear, passenger front, driver front.

 

[texasboy21]

1. Maybe they have been heated and cooled so many times it has gassed out leaving the material very hard lack of grab?
2. Never used one.
3. Yes, it's shared via the black hose on the side of the reservoir.
4. From far to close to the brake reservoir so passenger rear, driver rear, passenger front, driver front.

Since the fluid is shared, I assume bleeding the clutch is also required.

Does the clutch line require higher pressure than the brakes?

 

[NightmareMoon]

1) Is it normal for the stock pads to loose their initial bite so quickly?
Yes. Mine lost that wonderful initial bite pretty quickly also. I believe that bite goes away once the pads wear down a bit, and I don't think its related at all to brake fluid getting old (but it could be), since I've bled mine probably 4 times since I got the car and the initial bite never really came back.

2) What pressure is recommended for the power bleeder?
I wish I knew.

3) Does the clutch line share the same fluid/reservoir as the brakes?
The main reservoir feeds both the brake master cylinder and the clutch system, but the brakes and clutch are not one single pressurized system. You can see the clutch feed line visible on the lower driver's side of the reservoir. Its about 7" long and goes down to the firewall. (There is a whole thread on that line because on a lot of cars it looks like its about to fall off!) You only need to bleed the clutch if you want to bleed the clutch. Its not required to bleed the brakes.

4) What order should the brakes be bleed?
Typically its farthest wheel to closest, remembering that you need to bleed both sides of each front caliper (there are two bleeder screws). Left Rear, Right Rear, Left Front (both), Right Front (both). I haven't checked to see if the rear brakes actually share any line, they may be separate lines from the ABS unit, which sort of makes bleeding in any particular order not so important.

 

[texasboy21]

1) Is it normal for the stock pads to loose their initial bite so quickly?
Yes. Mine lost that wonderful initial bite pretty quickly also. I believe that bite goes away once the pads wear down a bit, and I don't think its related at all to brake fluid getting old (but it could be), since I've bled mine probably 4 times since I got the car and the initial bite never really came back.

2) What pressure is recommended for the power bleeder?
I wish I knew.

3) Does the clutch line share the same fluid/reservoir as the brakes?
The main reservoir feeds both the brake master cylinder and the clutch system, but the brakes and clutch are not one single pressurized system. You can see the clutch feed line visible on the lower driver's side of the reservoir. Its about 7" long and goes down to the firewall. (There is a whole thread on that line because on a lot of cars it looks like its about to fall off!) You only need to bleed the clutch if you want to bleed the clutch. Its not required to bleed the brakes.

4) What order should the brakes be bleed?
Typically its farthest wheel to closest, remembering that you need to bleed both sides of each front caliper (there are two bleeder screws). Left Rear, Right Rear, Left Front (both), Right Front (both). I haven't checked to see if the rear brakes actually share any line, they may be separate lines from the ABS unit, which sort of makes bleeding in any particular order not so important.

Great information, thank you nightmare! If the loss of bite is normal I will hold off on fluid, and stick with my usual annual flush.

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