brake fluid flush

[The Radium King]

got a question. if i bleed my brakes approx 5 times per year and run 500 mL of RBF600 through each time, you think there is any need for an annual flush?

[thstone]

The typical brake flush uses ~2 liters of brake fluid. Since you're replacing 1/2 liter x 5 times per year (~2.5 liters), you are more than flushing the whole system over the course of a year and can probably skip the yearly flush.

[Mark_T]

Why do you bleed your brakes so frequently? Not saying you shouldn't, or being critical in any way, just curious.

[Homeboy981]

Track Days. You do a lot of track days, right?
Jealous!

[san rensho]

Just a suggestion. You really should flush, not bleed the brakes before each track day because brake fluid, and even more so, race fluid,absorbs water. You need to get new fluid into the entire system. I use a little less than a litre to flush the entire system. If you alternate between ATE blue and gold, you know exactly when you have gotten the old fluid out.

[The Radium King]

yes i should. i swear by the motul after cooking ate, but do understand that the same qualities that make it a higher temp fluid also make it like water more. where i live, however, i gotta ship it in by the 1/2 litre and it is expensive. also, never quite know when i am done a flush - they should make it in two colours like ate.

i should just suck it up and flush instead of bleed after every track event - same amount of work (as long as i don't do the clutch - ug).

[san rensho]

You cooked the ATE? Its not the best fluid but its not bad. I've only used Ate on the track with my stock car and never had a brake fluid problem. Did your brake go to the floor on the track? Motul is great fluid but you might want to try a flush with ATE blue, so you are sure the system is completely flushed.

[The Radium King]

didn't loose the brakes (i tend to loose third before i lose the brakes - gotta get a transmission cooler going) but the fluid was obviously cooked when i bled them afterwards. put motul in and never a problem since. i'm going to run a full litre through on my subsequent bleeds, ignore the clutch, and call it good.

[stephen wilson]

Have you had brake problems with your current procedure? If not, there's no real reason to change, and use more fluid than necessary.

[thstone]

Interesting. I do ~25 track days a year and heat the brakes to the point of smoking on a somewhat regular basis yet only do a fluid flush every year and never have a problem.

Occasionally, I experience "pad fade" where I have to exert much more pressure than normal to get the car to slow down but the braking performance recovers to normal after the brakes have cooled. What symptoms are you experiencing that points to boiled brake fluid?

[Flavor 987S]

Originally Posted by thstone

Interesting. I do ~25 track days a year and heat the brakes to the point of smoking on a somewhat regular basis yet only do a fluid flush every year and never have a problem.

Interesting.

Are these PCA events?

How do you properly pass tech inspection, with only a yearly brake fluid flush? I know our Chicago Region PCA requires a brake fluid flush between track events to properly pass tech inspection and the form that is signed by the driver.

[jb92563]

Brake fluid absorbs water but with only the small surface of the Brake fluid reservoir and capped at that, where could all this water be coming from that the fluid is absorbing?

Just asking. I always thought that air bubbles were the culprit of a soft pedal.

Boiling the fluid is another matter and I thought those antisqueel pads served dual purpose of insulating the pistons from the source of heat (Brake Pads) and hence prevent boiling the fluid.

A good supply of cooling air could also help that situation which I read can be improved by installing the Carrera 4 front brake air directors.