Brake Fluid Change

[Al D]

Planning on bleeding my brakes tomorrow following an excellent but quite harsh bank holiday session at Bedford GT circuit with Easytrack. Does anyone know how much brake fluid would be required for a complete fluid change rather than just a bleed? And are there any recommendations as to the order in which the callipers should be bled?

Many thanks,

Al

[joust]

All I know is you need to use a pressure bleed system that atuomatically tops up the fluid. Sure if you ring the factory in the morning they can tell you more.

J

[broad]

As long as you keep a constant eye on the fluid level you should be fine without a pressure system. An assistant would help here for that very purpose too.

Play on the safe side and get a litre of brake fluid in. Complete brake kits from the likes of AP usually only come with 1 litre of fluid and in practice you normally use much less.

As for order - always start at the caliper furthest away from the master cylinder (i.e. rear - diagonally opposite the master cyl) and work your way in.

HTH

G

[LaurenceFrost]

broad said:

As for order - always start at the caliper furthest away from the master cylinder (i.e. rear - diagonally opposite the master cyl) and work your way in.

This order is not always the case (although very likely).

It depends how the system is split. Best to check with the factory for the bleed order.

Also if the calipers have 2 bleed nipples, bleed the outside nipple first, then the inside, then move on to the next caliper.

[broad]

LaurenceFrost said:

Also if the calipers have 2 bleed nipples, bleed the outside nipple first, then the inside, then move on to the next caliper.

Also not always the case - although likely

G

[Al D]

Factory confirmed back left, back right, front left, front right. I have a dual bleed kit so I bled both sides of each calliper at the same time. Quite alot of air/bubbles in the old fluid so I was reasonably hopeful that the improvement in brake feel would be considerable. However, upon completion, brake pedal still feels too soft in my opinion (must be about 2 inches of travel under 'normal' braking force).

I phoned the factory again and spoke to a technician who told me that the AP callipers cannot be fully bled without first removing the pads, allowing the pistons to extend up to a 10mm piece of blocking wood, opening the bleed nipple and then pushing the pistons back in to the calliper! Apparently normal bleeding will not necessarily remove all of the trapped air? Looks like I'll be re-bleeding the whole system again at the weekend and another litre of 5.1 required!