White smoke after hard braking...??

[Adambbyrd]

Alright, so here's the whole rundown.. For the past few months ie been having to add brake fluid because of some phantom that was stealing it from my system, well I discovered that my phantom was a bad seal around the plunger on my master cylinder, so I replaced it, along with wheel cyinders. Along with the fluid loss, occasionally when i hit the brakes hard to really hard, when i start to go, some to a lot of white smoke would come out of the tailpipe, usually the amount of smoke correlated with the agressiveness of the stop. SO, when I took off the old cylinder, a bunch of nice, fresh, clean brake fluid pours out of my brake booster. I wiggle the little shaft around and get as much to drain out as I can, but obviously I couldn't get it all. Now, I'm bleeding all of my lines out with my girlfriend in the car pumping the brakes, and I'm in the process of bleeding the back passenger wheel, when she complains about it being hard to press the brakes, so she cranks the car and we carry on the process, when all of a sudden after about the third pump-hold-pump a plume of white smoke starts pouring out of the tailpipe (and into my lungs...) the smoke is white but not steam (it's too thick and the head gasket isn't blown, I've done all the checks, short of a leak down test.) an smells... funky. So we turn the car off and just finish bleeding them the old fashioned way. So my question is: has anyone else had something similar happen? Could it be that my booster is so full of fluid that the vacuum line is just sucking up brake fluid? If so, how bad could that be for my engine?

[Jblair]

Sounds like that is whats happening. Brake fluid isnt designed to be in the engine. If you fixed the.problem with the master cylinder is should stop. Brake fluidis.hydroscopic, that means it loves moisture, its gathering in the exhaust because water vaper is a by product of.combustion, brake fluid is not good in patrolium based liquids, you dont want it to continue.

[1chrisapple]

Just take the booster off and flip it up so all the fluid will drain out the vaccum port hole.bc if left in it.it will eat the rubber away in the booster.and the engine will never suck it all out.whats happeneing is its about half full of fluid and when u brake hard it forces the fluid up agianst the front of boost and the engine sucks some in through vaccum hose on booster and smokey is what u get.good luck. You could just swap in a aspire booster instead of gettin fluid out.

[Larry Hampton]

You'll likely need a new (to you) booster too

[zoom zoom]

There's a check valve in the vacuum line too.

[Pu241]

Brake fluidis.hydroscopic, that means it loves moisture, its gathering in the exhaust because water vaper is a by product of.combustion, brake fluid is not good in patrolium based liquids, you dont want it to continue.

Ok, lets get some clairification.
It is true DOT 3 brake fluid is hydrospopic, DOT 4 less so, DOT 5(silicon oil) is not hydroscopic.

The brake fluild is NOT "gathering in the exhaust because water vapor is a by product of combustion"!
It is true that water vaper is a by product of combustion.

The brake fluid is being partially burned in the the engine and is no longer brake fluid.
It is creating white smoke because of the partial combustion.
The engine does not have enough oxygen, to completely burn the brake fluid under the conditions the engine is operating at.

If in fact if "its gathering in the exhaust because water vaper is a by product of.combustion", couldn't the OP just open the port on the vacuum booster on a humid day and the brake fluid would just magically come out to join its friend water vapor?

[navdoc101]

It does ! I've personally seen them partying on the front bumper!

[1chrisapple]

Ok, lets get some clairification.
It is true DOT 3 brake fluid is hydrospopic, DOT 4 less so, DOT 5(silicon oil) is not hydroscopic.

The brake fluild is NOT "gathering in the exhaust because water vapor is a by product of combustion"!
It is true that water vaper is a by product of combustion.

The brake fluid is being partially burned in the the engine and is no longer brake fluid.
It is creating white smoke because of the partial combustion.
The engine does not have enough oxygen, to completely burn the brake fluid under the conditions the engine is operating at.

If in fact if "its gathering in the exhaust because water vaper is a by product of.combustion", couldn't the OP just open the port on the vacuum booster on a humid day and the brake fluid would just magically come out to join its friend water vapor?

tooo funny lol

[Adambbyrd]

Alright, I'll take the booster off, as much as I'm not looking forward to it. I'm 6'3" and have sausage fingers, so under the dash work is a pain, especially on the itty bitty festy.. Ill probably just make my girlfriend do it.. But this hasn't been going on for too terribly long, so hopefully I won't need a new booster, but I probably will.. Brake fluid seems to eat anything it touches..

[Adambbyrd]

If in fact if "its gathering in the exhaust because water vaper is a by product of.combustion", couldn't the OP just open the port on the vacuum booster on a humid day and the brake fluid would just magically come out to join its friend water vapor?

Haha I tried that already. I think they're on bad speaking terms right now..

[Adambbyrd]

You could just swap in a aspire booster instead of gettin fluid out.

What would be the benefits of the swap? Are they better, or just easier to find?

[nitrofarm]

What would be the benefits of the swap? Are they better, or just easier to find?

Get the ATX Aspire booster not the MTX (Its larger).The benefit is larger surface area inside booster = more force applied to the plunger. Same amount of pedal input will yield MORE force applied to your brakes.

[Damkid]

^^i have a protege booster on mine, probably bigger then the aspire one

[Adambbyrd]

Get the ATX Aspire booster not the MTX (Its larger).The benefit is larger surface area inside booster = more force applied to the plunger. Same amount of pedal input will yield MORE force applied to your brakes.

Nice! Ill keep an eye out for one at the junkyard next time I'm there.

[nitrofarm]

Nice! Ill keep an eye out for one at the junkyard next time I'm there.

I wouldnt delay replacing it to long. Depending on the brake fluid used,the diaphram may start to break down from the oil. :thumbs_up: