Using compression fittings in brake lines. Ilegal?

[The_Eric]

So, let me start off by saying that I know it's very ill advised to use a traditional compression style union in a brake line repair. It is not in question and not up for discussion.

What I'm after is, is it illegal by federal or maybe State of Iowa standards? I've done some searching on the web and found many references to it being shady, dangerous and also illegal, but no links pointing to a website saying as much. I have seen a few links to other states and a few federal standards governing heavy trucks stating that they'll fail inspection, but it's not quite what I'm after.

 

[robshelton]

I have thought about this very thing many times and while I didn't look very hard, I have not found a particular law that addresses it. However it's obvious if the compression fitting fails whoever installed it is going to be liable. So I'd tend to stay away except under some odd circumstance where it had to be done. And then only for temporary use. Probably not the answer you are seeking but... Good luck!

 

[Silk]

In what situation would you need to use a compression fitting rather than double flare in a brake pipe....unless you are being dodgy?

 

[pompadour]

if you farmer bodge together something so [censored], it should just be to drive it to the mechanic or to the parts store for a whole new brake line. on top of that, you should not let anyone other than yourself drive it while it is like that.

 

[The_Eric]

I should clarify a bit... A guy and I were having discussion on auto related topics when this type repair came up. He claimed he'd been doing this for many years with no troubles. I said that everything I'd read suggested not to do this. After the conversation I recapped the story to a friend who brought the legality of it into question.

 

[eljefino]

http://www.maine.gov/dps/msp/vehicles_inspections/documents/InspectionManual_000.pdf

page 45, illegal here. Not only do you not get a sticker but you can't modify your car after the fact against inspection rules.

 

[Maritime Storm]

It's illegal here in New Brunswick as well.

 

[mechtech2]

I have heard it is illegal. [brake line union fittings]
It is also illegal to repair/weld suspension parts, like control arms.

But have I done it? Sure!

[And they can be permanent and perfect.]

 

[sciphi]

Highly illegal. Automatic fail on a NYS inspection. If you didn't torque it down or it jars loose, there go the brakes. Going down a mile-long hill through somebody's house because your brakes just blew off the compression fitting isn't worth the time or money saved.

Gas lines, they don't care if it's black magic. Then again, a 45 PSI gas line under fairly constant load is very different from a brake line that goes from no pressure to lots in a second or less. Plus ABS doing its own pressure/depressure thing.

Besides, 3/16" brake line is easy enough to do. I don't get why somebody would do a compression fitting when a double flare isn't all that hard...

 

[Shannow]

I've used compression fittings (swagelok et al) on all sorts of applicatins.

3000psi hydrogen, 2600psi steam etc.

I would use them as a trail fix to get back home from 4 wheeling, but would NEVER install them as even a semi permanent fix on a road going vehicle.

I've also seen many many failures of these fittings (well technically the pipe) when subject to vibration in service.

The little "olive" is designed to bite into the pipe. It creates a notch, and also becomes the node for any vibrations of the pipe itself.

Maximum bending stress, at a notch, and the pipe WILL fail eventually. Sometimes it's a month, sometimes it's half a decade. You just don't know when.

 

[parimento1]

What is a flared fitting...just curious?

 

[eljefino]

Double flare on the left, bubble on the right.

Interfaces with the joiner or master/wheel cylinder. Gets crushed a bit when the nut is torqued down for that perfect fit.

 

[Steve S]

Originally Posted By: eljefino

Double flare on the left, bubble on the right.

Interfaces with the joiner or master/wheel cylinder. Gets crushed a bit when the nut is torqued down for that perfect fit.
The tools aren't super expensive to do the proper flares and are pretty eassy to do with minimal practice.

 

[The_Eric]

Yeah trust me, the point isn't lost on me. I'm a big proponent of flaring a line. But then again I love doing all sorts of things like that.

Like I said, the question is legality in the state of Iowa or is it a federal law? I called the Iowa dot and they were of no help.