Brake fluid shelf life

[kurquhart]

In prepration for Streets, I bled my brakes today. A complete flush consumed about 0.75 litre from a can (ATE gold) that I just opened today (purchased about 9 months ago).

Am I correct in assuming that the remaining 0.25 litre is of little value for a track car, as it will begin absorb water right away?

[kary]

Yes, but it all depends upon how much you boil your brakes. I usually do not have to bleed brakes for a few events with the exception of the speedway!

[Steve Grosekemper]

Kris,
The stuff in the can will last only marginally longer than the stuff in the car as the master cylinder reservoir is open to moisture and the can is only exposed to the moisture that entered when you opened it.

I usually just flush an entire liter through just so I feel I have not wasted anything and who heard of fluid that was too clean??

That and I have more space on my bench where that almost empty can would be.

I usually change the fluid on a tracked car every 3 months unless there are problems or you are going to Fontana!!!!
That place is just brutal on brakes.

My 914-6 once went through a new set of Pagid Oranges in one day with 2 drivers!
Ya, I could have gotten of the gas sooner.... but what's the point in that...

[kurquhart]

Thanks for the fluid info, guys.

I would not have guessed that Fontana would be so hard on brakes. Don't they get a chance to cool down on the oval?

[Steve Grosekemper]

Oh, they cool down great on the oval!
Then you bend the brake pedal trying to brake at the very last second from 135+ down to 35 for the entrance to the infield.
Then full gas for a few seconds and brake!
Now do this several more times before you get back to the oval and all that cool high speed air.

The problem is you build up all this heat coming into the infield and there is not much speed for cooling and several quick gas-brake sections.

You just build up more heat than you can take away until you get back to the oval.

Come with near new front brake pads and brand new fluid.

Great track to drive, just brutal on brakes...

[ttweed]

Kris,
The stuff in the can will last only marginally longer than the stuff in the car as the master cylinder reservoir is open to moisture and the can is only exposed to the moisture that entered when you opened it...

Being a thrifty Scot by heritage, I always save the leftover 1/4-can (tightly capped) in my trailer, for emergency topping off of the master cylinder reservoir in the future. If you have to do a quick bleeding at the track because of fade, you usually don't need to do another full flush, you just need to pump out the few bubbles that have accumulated in the caliper, so having a small amount of replacement fluid to top off can be useful. It will still be fresher than what is in the system, and you won't have to open a new can just to bring the reservoir back up to full.

If I haven't used the leftovers by the next time I flush the brake system, it gets disposed of with the dirty fluid and the next can takes its place. Since going to 930 brakes on my early car, with good cooling, I have never once had to do any emergency bleeding at the track again, but my old habits persist.

TT

[Dan Chambers]

Kris:

I don't know about the ATE Gold, but the Super Blue seems to last okay in the can. I seem to recall that Super Blue absorbs less moisture from atmosphere than other brake-fluid compounds ..... Is that correct, Steve G.?

As a rule I completely bleed my brake system every January with 1.5 to 2X the fluid volume of the system (usually a full can of Super Blue). Then, every 3 AX's or before a TT I'll do a real quick (maybe a couple of ounces out of each caliper) bleed when checking pads and prepping the car for the big track. That means 2 Super Blue cans every January: 1 for complete bleed and 1 for "kwickie bleed" throughout the year. Cost: about $25 to $30. Value and peace of mind .... priceless.

BTW: with a power-bleeder or similar device bleeding is a snap, and not messy at all.

Good luck with that. Also, I'll have my Power Bleeder at Streets in case you need it (although Streets is a different story than Fontana...)

See you this weekend?

[kurquhart]

Being a thrifty Scot by heritage, I always save the leftover 1/4-can (tightly capped) in my trailer, for emergency topping off of the master cylinder reservoir in the future. If you have to do a quick bleeding at the track because of fade, you usually don't need to do another full flush, you just need to pump out the few bubbles that have accumulated in the caliper, so having a small amount of replacement fluid to top off can be useful. It will still be fresher than what is in the system, and you won't have to open a new can just to bring the reservoir back up to full.

If I haven't used the leftovers by the next time I flush the brake system, it gets disposed of with the dirty fluid and the next can takes its place. Since going to 930 brakes on my early car, with good cooling, I have never once had to do any emergency bleeding at the track again, but my old habits persist.

TT

That sounds like a good plan, thanks!

[kurquhart]

Kris:

I don't know about the ATE Gold, but the Super Blue seems to last okay in the can. I seem to recall that Super Blue absorbs less moisture from atmosphere than other brake-fluid compounds ..... Is that correct, Steve G.?

As a rule I completely bleed my brake system every January with 1.5 to 2X the fluid volume of the system (usually a full can of Super Blue). Then, every 3 AX's or before a TT I'll do a real quick (maybe a couple of ounces out of each caliper) bleed when checking pads and prepping the car for the big track. That means 2 Super Blue cans every January: 1 for complete bleed and 1 for "kwickie bleed" throughout the year. Cost: about $25 to $30. Value and peace of mind .... priceless.

BTW: with a power-bleeder or similar device bleeding is a snap, and not messy at all.

Good luck with that. Also, I'll have my Power Bleeder at Streets in case you need it (although Streets is a different story than Fontana...)

See you this weekend?

From what I have read on the internet (gotta be true, right?), the blue and gold are exactly the same except for the color. By alternating between them, you can better tell when you have flushed all the old fluid out of the system.

I did use a power bleeder. I do have to admit to 30 minutes of bewilderment until I realized that there was a vent tube off the reservior that needed to be plugged.

Yes, I will be at Streets. Vivian will be accompanying me again, but one look should tell you why she isn't driving.

[Jad]

Yes, I will be at Streets. Vivian will be accompanying me again, but one look should tell you why she isn't driving.

Yes, she does look too smart to risk life and loads of money driving in silly circles

Congratulations!

PS. It was nice knowing you

[kurquhart]

Yes, I will be at Streets. Vivian will be accompanying me again, but one look should tell you why she isn't driving.

Yes, she does look too smart to risk life and loads of money driving in silly circles

Congratulations!

PS. It was nice knowing you

[Dan Chambers]

Yes, I will be at Streets. Vivian will be accompanying me again, but one look should tell you why she isn't driving.

Monica and I look forward to seeing both of you at Streets. And it sounds like congratulations are in order.

[kurquhart]

Yes, I will be at Streets. Vivian will be accompanying me again, but one look should tell you why she isn't driving.

Monica and I look forward to seeing both of you at Streets. And it sounds like congratulations are in order.

Thanks! We will see you there; just look for the white EZ-UP.