Brake problem.Over heating fluid??!!!!

[3R titanium]

Hi
after solution. after a small blast in the car I have really poor brakes. I can only describe it as a really long brake pedal. It starts as normal then as things heat up, the pedal travel is noticably longer than when I started. I'm thinkin onlong the lines of boiling brake fluid?
I have put new front pads in, mintex race.
Any suggestions welcome

Simon

[joust]

Sounds like your fluid has water in it. The Noble system isn't exactly 100% air tight, and hence brake fluid, being very hydroscopic, ages quickly.

Get it fully flushed.

J

[Ash M400]

Agree with J.

Go for DOT5, it is not hdroscopic, or however you spell it.

[alex s]

Ash M400 said:

Agree with J.

Go for DOT5, it is not hdroscopic, or however you spell it.

Dont Noble say not to use Dot 5...I could be wrong, best to check first.

[saucyboy]

That's weird I got the same problems recently and will be bleeding the brakes this week.

James

[joust]

Ash M400 said:

Agree with J.
Go for DOT5, it is not hdroscopic, or however you spell it.

Err - don't do that! Use 5.1. which is actually totally unrelated to DOT5 (confusing isn't it...)

If you use a non hygroscopic one (e.g. Glycol DOT 5), as moisture enters the system it is not absorbed by the fluid, and results in beads of moisture moving through the brake line eventually collecting in the calipers. Once that happens the water will boil under excessive use and result in vapour lock and potentially totally fail the system.

DOT 5 is also high compressible and foams a lot, resulting in even further pedal travel. DOT 5 should really only be used for show car applications or stored classic cars where non-corrosion is important.

J

[Ash M400]

joust said:

Ash M400 said:

Agree with J.
Go for DOT5, it is not hdroscopic, or however you spell it.

Err - don't do that! Use 5.1. which is actually totally unrelated to DOT5 (confusing isn't it...)

If you use a non hygroscopic one (e.g. Glycol DOT 5), as moisture enters the system it is not absorbed by the fluid, and results in beads of moisture moving through the brake line eventually collecting in the calipers. Once that happens the water will boil under excessive use and result in vapour lock and potentially totally fail the system.

DOT 5 is also high compressible and foams a lot, resulting in even further pedal travel. DOT 5 should really only be used for show car applications or stored classic cars where non-corrosion is important.

J

Thanks J

What a great source this site is.

I would never have known that.

Back to the manual for the correct fluid then.

[ajg31]

Why does it say DOT 4 in the handbook? Was this another typo?

[GreenV8S]

ajg31 said:

Why does it say DOT 4 in the handbook? Was this another typo?

DOT4 and DOT5.1 are very similar, DOT5.1 is a slightly higher specification.