Flip top leaking bad

[player1up]

My 73 /6 duster with manual disc/drum setup is dumping brake fluid from the reservoir. It's sloshing out of the top when I come to a hard stop or take corners really hard. I've bent the clip to put more pressure on the lid and it's a pain to flip it closed now but it still leaks. I even thought it was because the top opening wasn't straight so I milled it a little more straight with a file. ( don't worry, I cleaned it all before putting it back together )

What am I missing??

 

[doktor_x]

If the rubber seal on the underside of the lid is intact, all I can think of is it being too full and return pressure is forcing it out. I'm having trouble visualizing how it could slosh out without pressure.

 

[player1up]

Now that you say that.... I made a run home for lunch and was driving...aggressively, and by the time I made it home ( 5 miles ) the front part of the reservoir was dripping and was almost empty ( reservoir for the rear brakes ). Could a stuck proportioning valve cause too much pressure?
I'm half tempted to put a huge hose clamp around the thing to see if it's really blowing out.

This may or may not be related but I've also noticed that the front rotors get a little blued/black when driving hard

 

[chasduster]

be careful with brake fluid that crap is like gas.........it will burn your car up not crapin ya....

 

[sst3193]

Sounds to me like you have something's stuck causing way too much heat and boiling the brake fluid. Front brake hoses don't last forever and they are double layer. What I mean is, I've had hoses go bad, they'll let fluid out to the brakes and then collapse internelly, not let the fluid return.
I'd jack up the car, you should be able to spin the front wheels very easily, if not, find out why. Brakes get hot, thats their job but, turning black and blue sounds scary to me!

 

[player1up]

be careful with brake fluid that crap is like gas.........it will burn your car up not crapin ya....

It's a good thing that there isn't a hole lot underneath the MC...cept maybe the exhaust... um I'll check

Sounds to me like you have something's stuck causing way too much heat and boiling the brake fluid. Front brake hoses don't last forever and they are double layer. What I mean is, I've had hoses go bad, they'll let fluid out to the brakes and then collapse internelly, not let the fluid return.
I'd jack up the car, you should be able to spin the front wheels very easily, if not, find out why. Brakes get hot, thats their job but, turning black and blue sounds scary to me!

I've seen that before too, creates a one way valve in the brake line and cooks the rotors,wheel bearings, pads even melted a hub cap ( ford escort ).
The front wheels spin freely by hand and the rotors look normal when I drive "normal" but they tend to look a little dark when I stomp on them.
The part of the MC that is leaking is the front part ( small reservoir for the rear brakes ) so I'm not worried about the front.

Maybe it's a bum MC.... never had a bad "new" part before....yeah right :angry7:

 

[RedFish]

Is there any brake fluid above the rubber seal, between it and the metal cap ?
I really dont think you could slosh all the fluid out of the resivoir. My best guess would be a leak under the car letting the rear brakes drain. If the front rotors turn blue they are running far too hot. Front doing all the braking, lines hooked up backward, wrong pad material or crystalized pads are common causes.

 

[player1up]

Red, I'm guessing that the front is doing all of the braking.
The front has new calipers rubber lines and pads ( couple of months old ) replaced because of some uneven/pull during braking

The rear has new wheel cyls ( about 6 months old ) replaced because one was leaking and figured I should do both.

New master cyl, again a couple of months old. Replaced because the old one was leaking at the plunger into the floorboard.

 

[player1up]

Well, I finally got fed up with putting fluid in every couple of days and decided to check things out. So with infrared thermometer in hand I checked the temp of the discs/drums after the ride home from work and this is what I found.

driver front disc - 141.2*
passenger front - 139.8*
Driver rear drum - 134.6*
passenger rear - 96.0*

After some investigation I found that the wheel cylinder was stuck, stuck bad...had to use a BFG to beat the pistons out ( no I did not reuse it I just wanted to see why it was stuck ) I looked like it had brown waxy build up inside. Not sure what that's all about but I'm hoping it was the assembly lube they used on the rebuilt cyl, and it's more like a year old ( not 6 months like I thought.. had the guy at the parts counter look it up for me ).
I don't normally mention parts places by name but autozone surprised me when they had 3 in stock...$9.99 (saved my butt on the daily duster)