Brake time, fluid expired?
Seasoned HDF Member
Joined: Jan 2011
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From: Michigan 15 Minutes East Of Hell
Taking into consideration "hygroscopic" factors ... yes you could "boil" ( use that term loosely ) fluid that had been compromised. Consider the moisture absorbed into the fluid. It is heavier than the fluid, hence would travel ( over time ) to the caliper area. It's boiling point is much lower than the brake fluid so consequently it would get hot and boil, thereby evaporating, giving you air ( where the fluid had boiled ) in the system.
Elite HDF Member
Joined: Sep 2012
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From: N Texas
I justed changed my brake fluid with a Mityvac, not too hard. The fluid that came out looked just like the fluid that went in....fluid was about 3 1/2 years old but looked fine - who knows how necessary but why not just change it every 2-3 years, I guess.
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From: NW Ohio
Taking into consideration "hygroscopic" factors ... yes you could "boil" ( use that term loosely ) fluid that had been compromised. Consider the moisture absorbed into the fluid. It is heavier than the fluid, hence would travel ( over time ) to the caliper area. It's boiling point is much lower than the brake fluid so consequently it would get hot and boil, thereby evaporating, giving you air ( where the fluid had boiled ) in the system.
Road Master
Joined: Jun 2013
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From: north of the south pole
Considering steam takes up 1600 times the volume of water, if water boiled in your brake lines there would be a huge expansion and your brakes would lock up. Also water under pressure has a higher boiling point than water at atmospheric pressure. So if the water boils it expands, the pressure goes up, it condenses back to the liquid state and you're good to go again. Just dump the brake fluid and refill with water.
Seasoned HDF Member
Joined: Jan 2011
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From: Michigan 15 Minutes East Of Hell
Considering steam takes up 1600 times the volume of water, if water boiled in your brake lines there would be a huge expansion and your brakes would lock up. Also water under pressure has a higher boiling point than water at atmospheric pressure. So if the water boils it expands, the pressure goes up, it condenses back to the liquid state and you're good to go again. Just dump the brake fluid and refill with water.
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From: Minnesota
You can't equate the expansion/compression ratio of steam and compare it to hydrolic fluids,, that's not comparing apples to oranges it's more like apples to the tree.
Completely different.
Seasoned HDF Member
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From: Michigan 15 Minutes East Of Hell
You put it much more eloquently than I did. :>)
Road Master
Joined: Jun 2013
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From: north of the south pole
Come on guys I was being facetious. We know moisture in brake lines is bad. Even if it doesn't get hot enuf to boil. Can we say sieze piston?
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Seasoned HDF Member
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From: Michigan 15 Minutes East Of Hell
Outstanding HDF Member
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From: Minnesota
I've seen rust and pit's caused by water sitting in master and slave cylinders when vehicles have been stored a long time.
I guess to add more here I had a rear brake switch go bad and replaced it last year, so I had to bleed the rear brake,, while I was doing that I flushed the front brake system too just to get clean fresh fluid in it.
It's easy maintenance that should be done every so often.
When I was a kid learning my way around a wrench, the old guy in the neighborhood that helped us drilled into our heads that ya need to be sure they stop before you make'm go. He was into racing stock cars and I think he lost a brother or Uncle because of bad brakes. His lessons have not been forgotten.
I guess to add more here I had a rear brake switch go bad and replaced it last year, so I had to bleed the rear brake,, while I was doing that I flushed the front brake system too just to get clean fresh fluid in it.
It's easy maintenance that should be done every so often.
When I was a kid learning my way around a wrench, the old guy in the neighborhood that helped us drilled into our heads that ya need to be sure they stop before you make'm go. He was into racing stock cars and I think he lost a brother or Uncle because of bad brakes. His lessons have not been forgotten.