brake line rust

Cite? My understanding is that rustoleum is simply regular paint with a dose of fish oil and other ingredients designed to make the paint waterproof - NOT to convert any of the various iron oxides to something else. Or were you referring to their "Rust Reformer" and not to their paint and/or "Rusty Metal Primer?"

nate

That particular test says some brake fluids failed the storage test and some didn't.

"there was no discernable pattern regarding commonality of

failure under these test conditions"

In other words they had no specific explanation for the failures.

More like there was no certainty.

In other words, it said nothing at all about how brake

lines might corrode internally.

I have not seen any brake fluid reservoirs that were designed to be open to the atmosphere.

The study made no claim that water was getting into stored brake fluid. To test the effects of water on

fluid that had been stored for 5 years they had to first add water.

Usually the customer would pay ford for fluid changes.

They quantified the amount of water and it was well below the point that brake fluid can tolerate without being harmful.

Second owners have exactly the same warranty rights for the duration of the warranty that remains from the time they purchase the vehicle.

It's about 50/50 in my experience. Some (mostly older vehicles) have a vent hole, some have the little rubber diaphragm thing that supposedly separates the top of the fluid from the atmosphere. The latter isn't a perfect solution, but it's nice to see someone making an effort.

nate

Vented master cylinders are legion and easy to find, and yet he confidently and (ultimately embarrassingly, should he possess that capacity) proudly proclaims never having witnessed so much as a single application bearing one. His unfamiliarity with them only serves to provide even further proof that he clearly doesn't begin to have a clue as to what he's talking about. Of course, the below again won't change his mind an iota, as there's precious little chance that he will understand what he is reading or viewing this time either.

You still have nothing but hand-waving innuendo. You haven't shown any evidence water plays any role to cause the corrosion that occurs wherever sediments settle inside brake systems.

And yes now that you mention it, I do remember seeing single piston master cylinders from the 50's with no diaphragm under the lid. The lid of course always needs a vent. The diaphragm wouldn't work if the cap above it wasn't vented.

-jim

Her>

I live in the desert and I've never had a brake line rust out even on

I read an article where they interviewed a Ford engineer about brake fluid and changing it and he said that the regular brake fluid will relatively quickly (in about a year) absorb up to 2 to 3% water but after that unless you are always opening up the system for some reason it won't absorb much more. He said he didn't think there was any reason to worry about it and to just do the flush that should be done whenever you have new pads/shoes put on.

Seems to me that what some people keep ignoring is that in the real world, very very few people seem to be having problems related to water in the brake fluid. That experience base combined with manufactures research suggests that absent some unusual operating conditions for your vehicle, there is really no reason to bother with "maintenance" fluid flushes.

That's because you live in the desert.

Here in salt country they rust from the outside in. Every time I've looked into why a brake line failed it was in a spot hidden from view where dirt and salt could build up or was inside a wheel well where it got blasted with salt and dirt. And usually those lines didn't fail until I had to take a wrench to them for another reason. Bottom of the line, top of the line, low point in the system higher up in the system... didn't matter.

However, lines last surprisingly long after they start looking bad.

Most people never have the brake fluid flushed. Ever. Do they get optimal performance? Probably not. Do they have any greater instance of stuck calipers etc? Hard to say.

Yup, the salt, dirt and water LOVE steel. I replace a lot of lines that are rotted through. Most vehicles have spots where the lines and a body mount or similar are close. On the GM S/T P/Us and Blazer styles for instance the worst spot is right in the drivers side wheel well, The fuel and brake lines come together there and the frame has a bend along with a body mount and a suspension mount all in that spot. I go in there every wash and clean it out.

If you really want to prolong the life of most vehicles it's a great idea to put them on a lift, then thoroughly clean the entire underside with either a pressure washer or a steam cleaner. Then spray it with something like a good undercoating or POR. Then do inside the body cavities as well.

I've never flushed my brake fluid (other than what happens when pads/shoes get changed) and have never had anything "rust out". Of the personal cars I've had since they were new and that I drove to at least 125,000 miles I've never had to replace any part of the brake system except pads/shoes and rotors and one master cylinder at

I don't doubt that at all. Certainly one of the advantages of living in a desert is that you don't have corrosion issues like you do in the snow belt.

My 92 explorer was coated from the factory with some kind of black gooey stuff all over the frame. Just a very thin but sticky coat that never became dry. It's still there in some areas. I presume it was a form of rust protection. I would think that for used vehicles a spray of that sort would be better then paint as it would not trap water like dried paint would. But I've never seen such a spray for retail use.

Sounds like what I've heard "krown" described as but apparently that's a Canadian thing.

nate

reading comprehension fail. i said "copper/nickel", not just "copper". it's a solid solution [if you know what that is] that can have great mechanical properties. and the one in question did.

as for "work hardening [1], fatigue[2], and cracking[3]", you're wrong because:

1. any cold drawn tube is highly work hardened. work hardening increases strength - a desirable property.
2. any corrosion causes pitting and this causes stress concentrations that initiate fatigue. materials that resist pitting and corrosion are typically much superior in real world fatigue applications because there are no initiators.
3. see #2. if you mean "stress corrosion", see "copper/nickel" above.