[rickybobby]

I flushed my brake fluid with dot4 before my first track day. I am experienced at doing car maintenance and properly torqued all bleeder screws. I had a nice firm pedal and drove the car for a week in the street and everything felt great.

At my first track day at Laguna I noticed some brake fluid weeping out of some of the bleeder screws. I tightened them and it seemed to fix the problem. I had a bit of a soft pedal so I re-bled them when I got home just to be safe. I also cleaned and dried all fluid just to be sure.

Fast forward to track day #2 and #3 I am still getting some weeping out of one caliper. When I looked at it tonight I think it is because there is some red powder coating overspray on the bleeder screws from the factory that are preventing me from getting a good seal.

Has anyone experienced brake fluid leaking at the track? Also, can anyone confirm if their bleeder screws are red like mine?

I have to decide if in want to remove and clean my bleeder screws or just get new ones. Or take it to the dealer for warranty.

[Try2paz]

No leaking at the track... I’ve heard of guys melting the seals in the calipers from running track pads and the brakes getting to hot.

I’d replace the bleeder and flush the system

[R3ctivision]

This happens to me at every track day when brakes get hot after I've done a bleed or flush. Never had a performance issue or a failure. I believe that when you flush or bleed the brakes, there is a little bit of brake fluid left behind inside the bleeder nipple. When you get the brakes really hot, I think that fluid maybe expands and then seeps out onto the caliper. Only once did my bleeder screw need to be tightened at the track.

I think it's safe to make sure they are tight before you go on track, and check after every session when the brakes have cooled a bit. If you see any seepage, wipe it up IMO. I often do up to four track days before the next bleed or flush, and usually the seepage does not recur until the next time I've opened the screw.

[kaamacat]

Just checked mine...and yes a small bit of overspray on my bleeder upper threads. (After thinking about it, I guess better to have the bleeder in there and attempt a full cover vs leaving out when doing the color application).

As for weeping. None BUT, when I bleed/flush I so take a small corner of paper towel and put in the bleeder hole to get that small excess out so when the caliper heats up it will not overflow onto the caliper. (small amount that it is)

[PROMETHEUS]

I use to get seepage on my corvette during track days. I assumed it was the brake fluid expanding from the heat. Never had any issues with the brakes on the track.

[gotswap]

Swap em out for speed bleeders, I do this for every vehicle when I bleed the brakes.

[rickybobby]

Thanks for all the responses. I thoroughly cleaned and dried all of the bleeder screws after the 1st track day bleed, so I’m fairly confident that it isn’t residual fluid. Especially since I got a soft pedal.

Since I’m down to only one leaking caliper, I’ll just remove and clean the 2 bleeders in question and call it a day. Maybe my car was built on a Friday as I also had a bad exhaust weld (covered under warranty).

[Rams01]

Not to bump an old thread but on my first track day June 8th I experienced this as well after having the dealer flush out the factory dot 3 for brembo H64 Dot 4 fluid. Pedal felt good on the street and stopped well and did great for the first 2 20 minute sessions at MSR 3.1 but on the 3rd session of the day the temps were around 100F and the car was getting sluggish and brakes were fading and oil temps were up so cut it short 15 minutes in when the brakes began to "let go" or so i assumed.
Drive the car home and throw it in park and brake fluid low light came on and of course the disabling of all stabilitrak, TCS, etc. Check the driver side rear and sure enough, fluid all over the wheel well which I thought was residual fluid left from the GM tech bleeding the system and leaving a mess.
Was down half a pint of fluid, had a buddy push the pedal and sure enough, fluid spraying out of the top bleeder screw which explained the crappy pedal feel and poor performance.
Any idea what went wrong or if its flat out user error and something I should have had on my checklist of things to check after each session? I'm still new to track racing so not sure if this is a common issue but some quick research shows that I am not the only person that's experienced this.

[rickybobby]

Originally Posted by Rams01

Not to bump an old thread but on my first track day June 8th I experienced this as well after having the dealer flush out the factory dot 3 for brembo H64 Dot 4 fluid. Pedal felt good on the street and stopped well and did great for the first 2 20 minute sessions at MSR 3.1 but on the 3rd session of the day the temps were around 100F and the car was getting sluggish and brakes were fading and oil temps were up so cut it short 15 minutes in when the brakes began to "let go" or so i assumed.
Drive the car home and throw it in park and brake fluid low light came on and of course the disabling of all stabilitrak, TCS, etc. Check the driver side rear and sure enough, fluid all over the wheel well which I thought was residual fluid left from the GM tech bleeding the system and leaving a mess.
Was down half a pint of fluid, had a buddy push the pedal and sure enough, fluid spraying out of the top bleeder screw which explained the crappy pedal feel and poor performance.
Any idea what went wrong or if its flat out user error and something I should have had on my checklist of things to check after each session? I'm still new to track racing so not sure if this is a common issue but some quick research shows that I am not the only person that's experienced this.

This sounds to me like the dealer simply didn’t tighten the bleeder screw enough.
In my case, I think it was the powder coating and wearing in if my bleeder screw threads that caused my initial leaking. I cleaned all my bleeder screws and don’t have an issue any more. That is a bit of residual fluid running down after I bleed no matter how well I clean it up but, no performance or fluid loss like you are describing.

[Stephen12ZL1]

You should definitely check the bleeders after the bleeding procedure because you need a little extra torque...not crazy just a little. After heat cycling (because of the expansion/contraction of metals) sometimes a little bit of loosening occurs. Always check your bleeders after the calipers have cooled or before the next track day. Mine dribble a bit...no worries.

[Whitespeed]

It also can take a few cycles of loosening and tightening for the bleeder and the seat to conform to each other and seal properly on new calipers.



Nigel

[AZ_1LE]

Originally Posted by Rams01

Not to bump an old thread but on my first track day June 8th I experienced this as well after having the dealer flush out the factory dot 3 for brembo H64 Dot 4 fluid. Pedal felt good on the street and stopped well and did great for the first 2 20 minute sessions at MSR 3.1 but on the 3rd session of the day the temps were around 100F and the car was getting sluggish and brakes were fading and oil temps were up so cut it short 15 minutes in when the brakes began to "let go" or so i assumed.
Drive the car home and throw it in park and brake fluid low light came on and of course the disabling of all stabilitrak, TCS, etc. Check the driver side rear and sure enough, fluid all over the wheel well which I thought was residual fluid left from the GM tech bleeding the system and leaving a mess.
Was down half a pint of fluid, had a buddy push the pedal and sure enough, fluid spraying out of the top bleeder screw which explained the crappy pedal feel and poor performance.
Any idea what went wrong or if its flat out user error and something I should have had on my checklist of things to check after each session? I'm still new to track racing so not sure if this is a common issue but some quick research shows that I am not the only person that's experienced this.

Yea, just a loose bleeder. There's kind of a fine line between tightening it enough, and too much. On the race cars in the Pirelli World Challenge, Brembo and StopTech gave us pretty precise torque values to tighten them to, and we did this before every session the cars went out on track. The heating and cooling will work them loose if they're not torqued right. I wish I knew the tq value for ours.

Also, we always sprayed the bleeder out with brake cleaner every time we bled the brakes. Will be a little rougher on our calipers since they're painted and some brake parts cleaner will etch the finish.

[Grifka_Garage]

Originally Posted by AZ_1LE

Yea, just a loose bleeder. There's kind of a fine line between tightening it enough, and too much. On the race cars in the Pirelli World Challenge, Brembo and StopTech gave us pretty precise torque values to tighten them to, and we did this before every session the cars went out on track. The heating and cooling will work them loose if they're not torqued right. I wish I knew the tq value for ours.

Also, we always sprayed the bleeder out with brake cleaner every time we bled the brakes. Will be a little rougher on our calipers since they're painted and some brake parts cleaner will etch the finish.

17-20 Nm for the bleeders

[SFV1LE]

On a different but related topic, I did notice my fluid reservoir cap would "sweat" and dribble some fluid during track days using Motul 660, which is supposed to be great DOT 4 racing fluid. After I switched to Brembo Racing and Castrol SRF this stopped completely, I assume the Motul 660 was boiling over and the others do not.

Also, I recommend everyone switch to braided SS lines.