Leaking Brake fluid Reservoir cap??

[danc5]

My 1998 A4 with 38000 miles on it has brake fluid that leaked out of the reservoir cap. The level is 1 1/2 " from the top. I have never opened the cap and it has never leaked until today. I don't understand how the fluid went up to leak??? Does the ABS pump fluid into the plastic reservoir? Thanks for any help. Why did it do this now after 5 yrs? It leaked a lot all around the seam of the plastic tank.

 

[c4c5specialist]

Cap seal???

Hi there,
I would suggest that you have the cap seal checked for leakage.
I have seen more than one leak slightly, giving seepage around the master cylinder.
Its not expensive for the cap, and is cheap to fix.
The ABS will not be an issue, as it recirculates the fluid inside the ABS control unit, and does NOT recycle the fluid back up into the master cylinder.
Please keep us posted, c4c5

 

[danc5]

Thank - You C4-C5 Specialist! Then It has been exposed to air also and needs the fluid changed. How did the fluid go up, to leak out? Is there any other preventaive matinance that should be done to prevent future expence?

 

[c4c5specialist]

Hi there,
While a brake fluid flush every 2 years is something good to do, most owners do not.
As for why it happened, many theorys could apply, hard cornering, brake fluid heating which forces a little out, cap not seated completely. I really can just speculate on the cause.
Nothing really can be done to prevent it, simply repair your cause now, and monitor the condition to see if it reappears.
Allthebest, c4c5