Bleeding brakes: Impossible due to system design??

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As article I posted says, moisture gets through microscopic holes in braking hoses. In Europe any vehicle with brake fluid older than two years or moisture level above 2% cannot pass inspection. There is a reason for that. Not to mention cooper levels in fluid.
So a brake hose that is required to withstand 4K PSI will allow moisture to weep in but no signs of fluid escaping?
**** that’s magic! That’s why cars should only be driven on sunny dry days! I am indeed enlightened. Pass me the Koolaid please. Thanks!
 
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So a brake hose that is required to withstand 4K PSI will allow moisture to weep in but no signs of fluid escaping?
**** that’s magic! That’s why cars should only be driven on sunny dry days! I am indeed enlightened. Pass me the Koolaid please. Thanks!
Assumption is mother of all screw ups.
Considering level of your “knowledge,” I have no doubt that ATE, TMD, Akebono, etc. are going to offer you huge money to work for them. You would resolve problem that plagues vehicles since brake fluid is used.

But, here is some basic reading. I mean, it is only OE supplier of brake fluid:
 
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So a brake hose that is required to withstand 4K PSI will allow moisture to weep in but no signs of fluid escaping?
**** that’s magic! That’s why cars should only be driven on sunny dry days! I am indeed enlightened. Pass me the Koolaid please. Thanks!
Again read how gortex works. Water in vapor form is something like the second or third smallest molecule. H20 is tiny. Because it is so polar it is attracted to itself and in liquid form behaves like a much larger molecule. It’s pretty easy to keep out liquid H2O and impossible or nearly impossible to keep out H20 in vapor form.
 
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Again read how vortex works. Water in vapor form is something like the second or third smallest molecule. H20 is tiny. Because it is so polar it is attracted to itself and in liquid form behaves like a much larger molecule. It’s pretty easy to keep out liquid H2O and impossible or nearly impossible to keep out H20 in vapor form.
If I had a nickle for every mechanic that know better than engineers that design vehicles.
 

JHZR2

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I’ve always flushed until the color changes. I don’t deny that the calipers hold a lot of fluid. If streamlines occur through the caliper body and don’t remove all the fluid, that’s a shame, and a poor design. I can see how it might happen on a fixed caliper where the hose and bleeder are on one side and the second piston is just a path… however I haven’t cracked enough calipers to know. I have rebuilt enough calipers to appreciate the reservoir inside, and the junk that is in there even if flushed and maintained.

I’m not a huge believer in the theory that the entire brake fluid network is mixing and dispersing moisture via brownian motion or whatnot, but it will happen locally, and will certainly happen in the caliper, which is good reason for why two year flushes are prudent.
 
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Since the manufacturer of brake fluid advises you to change your fluid every two years (wonder why) then you should. Let’s step in to discuss the moisture vapor molecules that enter your brake system… My advise is you should also purge and replace your Freon in your AC system every two years. After all, there is a low pressure-suction side that is drawing in those moisture vapor molecules that are entering your brake system also. In the spirit of safety I think you should be purging and replacing your power steering fluid every two years. Can you imagine how many of those moisture vapor molecules are being drawn into the return side of that system? To be totally safe and satisfied any Firestone store can perform these critical fluid and Freon exchanges. Be vigilant and safe. All these vehicles that crash everyday on our nations roads are because of moisture vapor molecules entering brake systems causing brake failures. Probably a large percentage is due to power steering failures. We are lemmings hurling to our deaths if we don’t visit a Firestone store and get these critical flushes done immediately. Edit: Why not also use a motor oil formulated for marine engines? Supposedly there are additives that help with moisture in your engine. If we buy in to this moisture vapor molecule invasion we might as well. Then there is marine gear oil that’s formulated to suspend moisture that could possibly enter the lower unit on outdrives. That would be a really smart investment in differentials and manual transmissions to fight off the moisture vapor molecule invasion and contamination. Also use marine based grease for suspension lube. So purging the old will be difficult but absolutely necessary. I’ve talked myself into completely switching over my vehicles. Living in the South with this heavy humid moisture vapor molecule laden air my cars are prime victims of this moisture invasion that results in all these catastrophic failures. I’m heading to West Marine to get my oil and grease.
 
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No offence but the more you post makes it look like the less you know, you sound more like a parts changer with little knowledge of basic automotive and fluid technology. I am just an old wrench turner but even I learned that in trade school.
A/C systems may contain Pag oil which is hygroscopic others (mostly older vehicles) may use mineral oil or ester based oils which are not, all have their issues.

As the charge lowers in the system over time (all will eventually) moisture ingress from atmospheric air is inevitable, to combat this a desiccant bag is used in the used in the system in the receiver/dryer to capture the moisture and prevent it damaging the system. For that reason any time the system is opened a new dryer is advised and the system vacuumed down, vacuuming actually boils the moisture so it can be drawn out by the vacuum pump.
Other fluids like PS fluid, engine oil diff and transmission fluids are not hygroscopic so moisture is not attracted to them.
 
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No offence but the more you post makes it look like the less you know, you sound more like a parts changer with little knowledge of basic automotive and fluid technology. I am just an old wrench turner but even I learned that in trade school.
A/C systems may contain Pag oil which is hygroscopic others (mostly older vehicles) may use mineral oil or ester based oils which are not, all have their issues.

As the charge lowers in the system over time (all will eventually) moisture ingress from atmospheric air is inevitable, to combat this a desiccant bag is used in the used in the system in the receiver/dryer to capture the moisture and prevent it damaging the system. For that reason any time the system is opened a new dryer is advised and the system vacuumed down, vacuuming actually boils the moisture so it can be drawn out by the vacuum pump.
Other fluids like PS fluid, engine oil diff and transmission fluids are not hygroscopic so moisture is not attracted to them.
I know. It was fun though!
 
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Since the manufacturer of brake fluid advises you to change your fluid every two years (wonder why) then you should. Let’s step in to discuss the moisture vapor molecules that enter your brake system… My advise is you should also purge and replace your Freon in your AC system every two years. After all, there is a low pressure-suction side that is drawing in those moisture vapor molecules that are entering your brake system also. In the spirit of safety I think you should be purging and replacing your power steering fluid every two years. Can you imagine how many of those moisture vapor molecules are being drawn into the return side of that system? To be totally safe and satisfied any Firestone store can perform these critical fluid and Freon exchanges. Be vigilant and safe. All these vehicles that crash everyday on our nations roads are because of moisture vapor molecules entering brake systems causing brake failures. Probably a large percentage is due to power steering failures. We are lemmings hurling to our deaths if we don’t visit a Firestone store and get these critical flushes done immediately. Edit: Why not also use a motor oil formulated for marine engines? Supposedly there are additives that help with moisture in your engine. If we buy in to this moisture vapor molecule invasion we might as well. Then there is marine gear oil that’s formulated to suspend moisture that could possibly enter the lower unit on outdrives. That would be a really smart investment in differentials and manual transmissions to fight off the moisture vapor molecule invasion and contamination. Also use marine based grease for suspension lube. So purging the old will be difficult but absolutely necessary. I’ve talked myself into completely switching over my vehicles. Living in the South with this heavy humid moisture vapor molecule laden air my cars are prime victims of this moisture invasion that results in all these catastrophic failures. I’m heading to West Marine to get my oil and grease.
Man, just stop.
Brake fluid actually attracts moisture! It is hygroscopic! And there is no way to get rid of ghat moisture. It is purposely designed that way.
You can use hydrophobic brake fluid, but ghat comes with other issues.
 
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Man, just stop.
Brake fluid actually attracts moisture! It is hygroscopic! And there is no way to get rid of ghat moisture. It is purposely designed that way.
You can use hydrophobic brake fluid, but ghat comes with other issues.
Ok. Sorry. Didn’t mean to upset you.
 
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Got it. I guess I speak from personal experiences, not so much from the written word. Just enjoy the debate. I kinda thought that’s what gearheads do??
 
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Got it. I guess I speak from personal experiences, not so much from the written word. Just enjoy the debate. I kinda thought that’s what gearheads do??
:*******: :*******: :*******:
How did you determine that moisture cannot go through microscopic pores in brake lines? Please, we are all ears, and I bet Bendix and Amsoil, among others, would like to know that.
 
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So a brake hose that is required to withstand 4K PSI will allow moisture to weep in but no signs of fluid escaping?
**** that’s magic!
That's the effects of diffusion and partial pressure.
This is why if you actually fill a tire with pure nitrogen, even though it is pressurized, oxygen will gradually find its way in from the outside air.
Besides, that brake hose on a typical passenger vehicle will be pressurized less than an hour a day.
The rest of the time moisture can drift inward with no opposing force, partial or otherwise.
When bleeding the fluid does not travel across this big compartment but the shortest distance close to the outer zone of said compartment. Almost NO fluid is drawn from the area furthest away from this entrance/exit zone. This is pure physics/fluid dynamics.
You're omitting some physics here: diffusion.
The moisture rich fluid will blend with the new fluid over time by way of thermal agitation, diluting the moisture.
Diffusion is fast in gases, slower in liquids, very slow in solids, (we wouldn't have transistors without it).
 
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Brake Fluid Liquid Tester, Auto Brake Diagnostic Testing Tool, Hydraulic Fluid Liquid Oil Moisture Analyzer with 5 LED Indicators, Auto Brake Diagnostic Testing Tool for DOT3 DOT4 Brake Fluid
Since I’ve shown my ignorance here and want to knock the hard crust off of my ancient attitude… Do y’all use a brake fluid moisture detector such as shown?
Wondering if this is an accurate way to detect moisture in brake fluid? I’d be curious to check mine at 5 years old and 72k. I won’t be ashamed to report my findings.
 
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Brake Fluid Liquid Tester, Auto Brake Diagnostic Testing Tool, Hydraulic Fluid Liquid Oil Moisture Analyzer with 5 LED Indicators, Auto Brake Diagnostic Testing Tool for DOT3 DOT4 Brake Fluid
Since I’ve shown my ignorance here and want to knock the hard crust off of my ancient attitude… Do y’all use a brake fluid moisture detector such as shown?
Wondering if this is an accurate way to detect moisture in brake fluid? I’d be curious to check mine at 5 years old and 72k. I won’t be ashamed to report my findings.
I have it. It is so so. A cheap device, so I would not trust it to be right on point.
I change the fluid in Tiguan every two years.
BMW? 2-3 times a year. I track that car. Small drop in dry boiling point and it can be a problem.
 
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