Brake Fluid boil over ?

[nicksm3]

Has anyone been dealing with this issue?.
I recently swapped out Castrol SRF fluid because I got wind from certain race cars and race series stopped using the fluid because they had brake failure because of the fluid.
I ran SRF in my E36 race car and same thing ….I was getting boil over everywhere. never happened in the past of all my years of tracking.
Open till the week ago, I swapped over to Motul RBF 700 and still getting boil over. Yesterday at Limerock after first session I check everything as usual and walla…it’s back. I’m stumped. Is the system on its last leg of failure ? Brakes are brand new… Stoptech ST40 Trophy with PFC Race Pads stock rear calipers with PFC race pads with upgraded rotors and braided lines.

With my E36 race car I just swapped out the SRF and put in endless 650 fluid as I’ve heard great things. I’ll keep whoever is interested posted.

[Ximian]

What level did you fill the fluid in the reservoir? I do it an inch or so below the maximum to avoid venting. It looks like it's on right but I always double check to make sure the two pieces of the cap are on tight.

[nicksm3]

Originally Posted by Ximian

What level did you fill the fluid in the reservoir? I do it an inch or so below the maximum to avoid venting. It looks like it's on right but I always double check to make sure the two pieces of the cap are on tight.

The level was actually right at the marker, what I’ve been doing for years.
After really thinking about this. I was on PFC BBK front and rear prior to this braking system I currently have. For me…I felt the PFC BBK was a bit over kill for my driving style. I do drive hard and I feel now the system is working alittle harder to compensate. Make sense? Maybe ? I’m dumb

[Redd]

Are you getting total brake loss when this happens? If the fluid is really boiling, you should have zero braking power.

[JohnnyBeagle]

I think you overfilled it

[roastbeef]

it doesn't "boil over" at the reservoir. you may have overfilled it and it is spraying out as it sloshes around venting off a litte pressure.
a more likely scenario is you overfilled it, then changed brake pads, and it pushed all the pistons back in the calipers, which pushed fluid out of the top.

[spammysammich]

Beware the vacuum pressure sensor.

[MPower7]

Originally Posted by nicksm3

I got wind from certain race cars and race series stopped using the fluid because they had brake failure because of the fluid.

Sorry what? Can you provide sources for this statement?

[Ximian]

Originally Posted by MPower7

Sorry what? Can you provide sources for this statement?

Plenty of posts on the internet about SRF corroding seals and things like that. I found tiny dark chunks in my brake fluid after a year of using SRF that wasn't there before or seen since switching to Endless or Motul.

Castrol SRF is nothing special and I'm pretty sure you can find similar posts about other brake fluids.

[nicksm3]

Originally Posted by Ximian

Plenty of posts on the internet about SRF corroding seals and things like that. I found tiny dark chunks in my brake fluid after a year of using SRF that wasn't there before or seen since switching to Endless or Motul.

Castrol SRF is nothing special and I'm pretty sure you can find similar posts about other brake fluids.

Precisely…found the same in my experience using srf

[M3SQRD]

I’m glad I never jumped on the SRF bandwagon. AP Racing and PFC for decades without an issue. I’d be concerned a major seal might fail if I had routinely used SRF.

[M3SQRD]

nicksm3

Did you calculate the front and rear caliper torque output and brake bias for the new StopTech brake kit and your PFC z54/z45 brake kit?

BTW, there’s no braking style that the PFC z54/z45 brake kits would not improve when using the PFC kits The z54/z45 kits can easily survive 45 min sessions without even coming remotely close to a softening pedal. PFC brake kits + PFC rotors + PFC pads, especially the 29 mm-thick pads, last forever! Rotors can survive 40 track days and the 29 mm-thick pads, depending on pad compound and track, can last 30-40 track days (< 1 mm of wear per day).

[nicksm3]

[QUOTE=M3SQRD;31468267]nicksm3

Did you calculate the front and rear caliper torque output and brake bias for the new StopTech brake kit and your PFC z54/z45 brake kit?

BTW, there’s no braking style that the PFC z54/z45 brake kits would not improve when using the PFC kits The z54/z45 kits can easily survive 45 min sessions without even coming remotely close to a softening pedal. PFC brake kits + PFC rotors + PFC pads, especially the 29 mm-thick pads, last forever! Rotors can survive 40 track days and the 29 mm-thick pads, depending on pad compound and track, can last 30-40 track days (