Dahlinboysracing: car and brake info (Page 1 of 2)

What kind of uneven wear were you seeing on the pads? Some types are normal, others might tell you that pads were sticking. You said you greased the slides, but if there was more buildup on the brackets than ususal from the car being outside more, or the new pads had backing plates that didn't fit as nicely, or a combination of both, the pads might have been sticking in the brackets and rubbing more than normal.

I highly doubt the Penzoil fluid has a boiling temp as high as more performance based fluids. I'm trying to find a spec sheet to confirm that. However, as that is more a street fluid, if you had pads that were wearing weird and indicating sticking, that could have contributed to more heat build up than normal.

When you say you bled the brakes before thompson, and again after practice, do you mean just bled where you check for no bubbles, or do you mean fully flushed where you tried to replace all fluid in the system? Did you use new previously unopened bottles of fluid each time?

Your ducts should be aimed at the rotor. The rotor is the main heat sink for heat generated during braking and most heat goes that way, not back to the caliper and fluid. You want air flow aimed at the center of the rotor so it can pull that through and cool between braking points. If you keep the rotor cooling properly that helps keep the pads cool and therefore everything upstream cool.

Lots of speculation in my post, just trying to give you things to investigate and think through.

Penzoil 4/3

https://prodepc.blob.core.windows.net/e … TDS_v1.pdf

One more post, about boiling fluid and why it's so scary. Boiling fluid doesn't come on like fading pads. Brake fade you can feel happen somewhat progressively. Fluid boiling is more like an on off switch. As the fluid heats up it will keep working more or less the same. And it won't boil mid braking point usually because of what happens when you pressurize a fluid. Boiling point increases as you pressurize a fluid. Same reason that water boils at a lower temp in the mountains because atmospheric pressure is lower. So under braking you pressurize the fluid, raise it's boil point, and if you have something weird going on with the brakes you can then push the fluid past the un-pressurized boiling temp while braking. Then when you release the pedal the pressure is reduced and the fluid, now over it's boiling temp, well boils and introduces bubbles. So next time you step on the pedal it's suddenly very soft, or basically nonexistent.

I can't say with 100% certainty that this is what happened to your car, because well I've never closely looked at the system or driven it. But the signs do point that way.

Never tried one, there are testers on amazon for $10.  Might be worth buying one and throwing in the tool box.

https://www.amazon.com/Brake-Fluid-Test … B005HVG4GQ

Sounds 100% like boiled fluid.

We boiled the fluid in our first Civic.  It was an 95 EX, so the same brake setup as the 95/96 Integra, minus the ABS.  Brakes work great until they don't.  Switched to Motul RBF600 and bleed it before every race.  Sometimes, depending on how much other stuff we are fixing, we will bleed for each race day as well.  Never had a bit of trouble with fluid since.

I was driving when we boiled fluid.  Turn 11 at CMP on the old short course (whatever corner number that would be).  Pedal didn't feel like it was there at all.  I can't recall if the pedal was coming up on each pump, or if it was stuck to the floor.  Drove straight off into the gravel/grass.  The pedal was back within a minute or two of stopping.  Speed was much lower and there was no traffic on the outside of 11 to avoid.  A lot less dramatic than your event.

What did the pedal feel like before the crash, does the driver remember?

Caliper temp strips: http://www.hrpworld.com/alc-ths0080x285-alcon-te.html

Also one quick google, and Crazy money for the crayons.

https://www.amazon.com/Tempstik-Test-Ki … B00Y95KCNM

Presumably the old ones were made entirely out of asbestos and uranium leavings.

You can buy individual sticks, but amazon and trying to find exact things = hate.

So you go here:
http://www.tempil.com/tempilstik/

and here:
https://www.amazon.com/Tempil/b/ref=bl_ … bin=Tempil

On the tempil site find the temp you want, look att he part number, then on the Amazon site search that part number at the top but stay in the Tempil search zone, don't search all of amazon.

Also it seems pricy, but 2oz of the paint will last a heck of a long time.

No I was able to find the individual ones and at $15 it's worth having a look, just not the whole big set.

+1 for what sounds like boil

Been using this stuff for years in our A car, full system flush every event,  perhaps overkill but @ the price it is no crime <$15 a qt
Shop around, looks like amazon is more expensive then shelf price @ my local parts store
Pentosin super dot 4
https://www.autozone.com/brake-and-powe … 579851_0_0
https://shop.advanceautoparts.com/p/pen … 10024311-P

Dry Boiling Point:    265°C/509°F
Color:    Yellow & Clear
Flash Point:    130°C/266°F
Melting Point:    >-50°C/>-58°F
pH Balanced:    8

All,

Thanks for the suggestion and ideas. To answer a few of the questions I keep seeing:

No leaks, bad lines were found, good pedal now.

No fluid boil over at master.

We have not bleed the brakes since we got home, nor looked at anything else.

Not a full flush on friday, not sure if any fluid was added, if it was it was form an open container.

I have ordered a brake fluid tester (the one linked from Amazon) it is supposed to be delivered Sat.

I will continue to update our findings.

Fritz

My take-away from all of this (because it did shake me to the core like many of us) is the following:

If, like us, you are sloppy about changing the brake fluid...stop.  It is an extra 15 minutes of bleeding for most of us.

Any, and my any, brake related weirdness means come in for us to check it out unless you have a driver so skilled they can slow the pace and try further diagnosis before just coming in (we have had that).

Newbie instructions should include a brake check before corners particularlly fast straight, tight corner combinations.  A side note on that is all newbies on our team have STRICT instructions if anything is wrong with the car, pull off adjacent the next corner station.  I doubt our recent new guys could have threaded that needle and I am not even sure I could have with 20+ races under my belt.

I always preach for new teams the mantra of: make it safe, make it reliable, make it brake, make it turn, then make it fast.  This holds true but keeping the first three up to date is so much more important that the last two.  We all are probably guilty of some version of letting those slide as we get "good" at Lemons.

Like I said, eye-openner for me and will change some of our habits.