Brake hose fluid gone "Milky"?

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Brake hose fluid gone "Milky"?
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flag benplatt
FL
Posted: Dec 5, 2008 at 12:25 Quote
My bike is in for service at the moment at my lbs as I asked them to fit a new hose and levers to my Formula K18s.
The guy rang me up and said he had successfully fitted them, however, when he took the rear hose off, the fluid came out white and milky?
Its not urgent but out of pure curiosity, how could this have happened?
The brakes came ready bled and I haven't done anything to them since then. I've tried to ask around about it but no-one will take me seriously and people just make sexual innuendos about my rear end having milky fluids in it!lol
Any ideas?
flag mr-wilson
Posted: Dec 5, 2008 at 12:32 Quote
As far as I know (may not be much) milky fluid is a sign of water contamination.
flag MajesticMOOSE
Posted: Dec 5, 2008 at 13:09 Quote
I'm pretty sure that mixing DOT3, DOT4 and DOT5.1 with DOT 5 fluid creates a milky precipitate inside the lines. Maybe your mechanic didn't properly bleed out the old fluid before adding the new fluid.
flag mr-wilson
Posted: Dec 5, 2008 at 13:10 Quote
Though never ever run DOT5 eats through seals like nothing, just ruins your brakes.
flag odin333
Posted: Dec 5, 2008 at 13:12 Quote
pretty sure that a milky hydraulic fluid happens when mineral oil has been worn out. not entirely sure what fluid formula uses, but that might be the problem.
flag MajesticMOOSE
Posted: Dec 5, 2008 at 13:20 Quote
mr-wilson wrote:
Though never ever run DOT5 eats through seals like nothing, just ruins your brakes.

I should have known that...
flag thecorporatemachine
Posted: Dec 5, 2008 at 13:21 Quote
LAWL

dot 5.1 ftw, is the good stuff lol.

tho yeah, dont cum in your hose!
flag jackterry123
Posted: Dec 5, 2008 at 13:26 Quote
Where did you buy them from?
flag jonbikes
Posted: Dec 5, 2008 at 18:39 Quote
mr-wilson wrote:
As far as I know (may not be much) milky fluid is a sign of water contamination.

I too believe that water is the cause of this milky appearance.
flag happysumo
Posted: Dec 5, 2008 at 21:45 Quote
Well obviously- It's Jizz.


Bet you haven't heard that yet
flag lcstay10
Posted: Dec 5, 2008 at 21:57 Quote
im pretty sure one of the mechs was having too much fun..
but jokes on him becsause he could fit in the tube.
flag benplatt
FL
Posted: Dec 6, 2008 at 5:49 Quote
odin333 wrote:
pretty sure that a milky hydraulic fluid happens when mineral oil has been worn out. not entirely sure what fluid formula uses, but that might be the problem.
Formulas use dot 4.
Got my bike back from the shop and the rear brake is really weak and the contact point is quite far out, so i just adjusted the lever reach and its all sorted!
flag irritatedmuppet
Posted: Dec 6, 2008 at 9:23 Quote
MOISTURE IN THE BRAKE SYSTEM
Water/moisture can be found in nearly all brake systems. Moisture enters the brake system in several ways. One of the more common ways is from using old or pre-opened fluid. Keep in mind, that brake fluid draws in moisture from the surrounding air. Tightly sealing brake fluid bottles and not storing them for long periods of time will help keep moisture out. When changing or bleeding brake fluid always replace master cylinder caps as soon as possible to prevent moisture from entering into the master cylinder. Condensation, (small moisture droplets) can form in lines and calipers. As caliper and line temperatures heat up and then cool repeatedly, condensation occurs, leaving behind an increase in moisture/water. Over time the moisture becomes trapped in the internal sections of calipers, lines, master cylinders, etc. When this water reaches 212º F the water turns to steam. Many times air in the brake system is a result of water that has turned to steam. The build up of steam will create air pressure in the system, sometimes to the point that enough pressure is created to push caliper pistons into the brake pad. This will create brake drag as the rotor and pads make contact and can also create more heat in the system. Diffusion is another way in that water/moisture may enter the system.

Diffusion occurs when over time moisture enters through rubber brake hoses. The use of hoses made from EPDM materials (Ethlene-Propylene-Diene-Materials) will reduce the amount of diffusion OR use steel braided brake hose with a non-rubber sleeve (usually Teflon) to greatly reduce the diffusion process
flag jonbikes
Posted: Dec 6, 2008 at 12:09 Quote
irritatedmuppet wrote:
MOISTURE IN THE BRAKE SYSTEM
Water/moisture can be found in nearly all brake systems. Moisture enters the brake system in several ways. One of the more common ways is from using old or pre-opened fluid. Keep in mind, that brake fluid draws in moisture from the surrounding air. Tightly sealing brake fluid bottles and not storing them for long periods of time will help keep moisture out. When changing or bleeding brake fluid always replace master cylinder caps as soon as possible to prevent moisture from entering into the master cylinder. Condensation, (small moisture droplets) can form in lines and calipers. As caliper and line temperatures heat up and then cool repeatedly, condensation occurs, leaving behind an increase in moisture/water. Over time the moisture becomes trapped in the internal sections of calipers, lines, master cylinders, etc. When this water reaches 212º F the water turns to steam. Many times air in the brake system is a result of water that has turned to steam. The build up of steam will create air pressure in the system, sometimes to the point that enough pressure is created to push caliper pistons into the brake pad. This will create brake drag as the rotor and pads make contact and can also create more heat in the system. Diffusion is another way in that water/moisture may enter the system.

Diffusion occurs when over time moisture enters through rubber brake hoses. The use of hoses made from EPDM materials (Ethlene-Propylene-Diene-Materials) will reduce the amount of diffusion OR use steel braided brake hose with a non-rubber sleeve (usually Teflon) to greatly reduce the diffusion process

Wait a sec, it's the weekend I'm not supposed to be in any science class!?!?

That is quite the explanation, I did not know about the diffusion bit, however it does make sense to some degree.
flag StevePrice
Posted: Dec 6, 2008 at 12:10 Quote
possibly youve gotz milk in it
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