Porsche_nuts

Do you have to remove some brake fluid from the master reservoir and leave the cap open when using a brake pad spreader to open the pistons when changing brake pads?

Sidvicious7

It all depends on your current level of brake fluid in your reservoir. I removed just a small amount when I replaced my brake pads to avoid an over flow last year.

008

No, they wouldn't fit when new then. Unless it was grossly overfilled.

StormRune

I agree with Sid. If it is at max you'll want to remove some in any case since the new pads should put you above max. Below that you'll need to keep an eye on it to make sure it doesn't overflow. I'd recommend each time you finish a caliper, you pump the pedal to push the pistons back out on the the new pads. That will bring the fluid in the master back down some so it is less likely to overflow on the next one. If you spread the pistons on all of the brakes before you pump the pedal to seat them you're more likely overflow the master.

BradB

I change pads and flush fluid on my 991 brakes several times a year (track days) and never pull any fluid out of the master cylinder reservoir prior to pushing back the pistons. I can take out thin dead pads, push back the pistons, replace with all new pads and not have an issue. At least that's my experience every time.

991carreradriver

+1

Porsche_nuts

Thanks for all the replies. Very helpful.