Brake Fluid Leaking from Fill Reservoir

[pinchvalve]

I have been noticing a pretty steady amount of brake fluid on the fuse box cover, just below the reservoir where you fill the brake fluid. Performance of the brakes has not suffered any, but how long can that last, right?

I had the brake fluid flushed and replaced with high-temp fluid by the Ford dealer, and this is when I noticed the issue. Dealers in my area are pretty horrible, so it may be that they messed it up. It could also be that the higher-temp fluid is somehow thinner and getting past the seal on the cap? m

The other factor that could be affecting it is the Koni dampers. To get to the adjuster, you have to move the reservoir out of the way, which I do often because I autocross the car. I don't see any leaks when doing this, but after a race, there is fresh fluid on the cover. WTF? Could it be from hard application of the brakes? Maybe there is a pinhole in a line that only leaks when racing?

Anyone else experiencing a leak from the fill reservoir area?

 

[M-Sport fan]

Did you already check the clamps on the hoses at the bottom of the reservoir?
(Dealer could have effed up when re-installing them after flush, why I am reluctant to let them do this, even though they may be my only choice. )

Is the reservoir even slightly over-filled?

 

[Plainrt]

I get the same thing time to time on mine. I just wipe it up and suck it up as it comes with driving a fiesta.

 

[Quisp]

Are you filling to the top ? Fluid expansion from heat possibly. Seal might be damaged from frequent movement. You definitely don't want brake fluid on painted parts. I would flush with a hose until leak is stopped .

 

[kivnul]

Old thread but I have some data to share. Last couple autocrosses I have noticed brake fluid on the fuse box. I paid better attention yesterday and the fluid is definitely coming out from the cap (even had a drip hanging from it). I checked my son's FiST and it happens to him as well. Brakes feel fine during use and the reservoirs were filled to spec. Both cars are on stock fluid, mine is 2 years old, his could be up to 4. I think I'll flush the lines with fresh fluid before the next autox weekend and see if it makes a difference. I do wonder if steel brake lines could make a difference.

 

[TyphoonFiST]

Brake Fluid is hygroscopic...translation.... it sucks the moisture out of the air when subjected to air and not sealed properly then changes the peddle feel.Food for thought to all those with this issue...keep us up to date with a fix or a how to!

 

[Intuit]

The most simple explanation is the most likely. They were overfilled. If you've topped off or have done a fluid change with less than brand new pads on all four corners, then you've likely overfilled. However the overfilling won't become evident until you replace some pads.

 

[kivnul]

[MENTION=5184]Intuit[/MENTION] - Most of the time I would agree with you but this is something I have been monitoring for a while. I can with 100% certainty say that prior to this weekend my reservoir was below the high mark. My sons fluid level as of 1.5 months ago was also below the full mark (and I do not believe he has added any in the interm.)

 

[kivnul]

Brake Fluid is hygroscopic...translation.... it sucks the moisture out of the air when subjected to air and not sealed properly then changes the peddle feel.Food for thought to all those with this issue...keep us up to date with a fix or a how to!

I flushed my brake fluid with fresh Motocraft just prior to this weekends AutoX. I did not see any new leaking from the cap but this weekend's course setups were relatively brake friendly. My son was not there this weekend so no data from him. This weekend was a wakeup call for tires though; my back two were practically melting. Was hoping to get 2 seasons out of the set but from the looks of it I need to take them to a tire shop to get them swapped left to right to get a few more sessions out of them. (I am not running near enough camber)

 

[chance]

This is a very old thread, but did anyone find anything causing this? My fill cap seems to leak too.

 

[pinchvalve]

Over 7 years, I’ve flushed and filled, changed pads, added SS lines, swapped caps…ST brake reservoirs leak. Add more fluid at the beginning of the season.

 

[kivnul]

Just something I live with. May someday cut up a sock to put around the cap to catch any fluid.

 

[ST-eph]

I have an AP racing big brake kit, and the only times I have had a leak from the brake fluid filler cap is when I reach the end of the pads' life. The liquid should boil more easily and after a circuit session, I can have it all over the engine compartment.