Compression fitting on brake lines

I have a 1992 5.7 l chevy conversion van. Last year during my inspection the mechanic said that I needed to have some brake lines replaced as the old ones had rusted out. I paid the guy 300 and he replaced 3 brake lines.

Just this past month I was replacing my rotors and while inspecting the brake lines I noticed the work that had been done and it concerns me. Not only did they not remove the damaged brake lines (they just cut off the ends and left them in place) but all of the new brake lines are connected with compression fittings - presumably because they didn’t have a double flare tool.

I worry because this van is so heavy and the brakes are already boarderline for it’s weight. Are these going to blow out on me someday when I’m going downhill with a full load? I’ve had warnings from other mechanics that this is dangerous and I’m ready to have the lines replaced. I still have the original reciept for the work as well as the failed inspection report. Is it reasonable for me to either demand my money back, or insist they re-do the brake lines they’d installed? or Is this an acceptable way to replace brake lines?

Yes! This is very dangerous! Compression fittings aren’t designed to handle the hydraulic pressure a brake system is imposses. That is why all brake fittings are flare type fittings. So the line can’t blow out of the fitting.

Go back and demand your money back. But don’t let them touch your vehicle. Because only an idiot would attempt to repair a brake line using compression fittings. But don’t wait to get this repaired the proper way. Because those lines could blow out at any time.


Yeah, yeehaw, man, that’d be fun when you get your brakes nice and warm, need to make a stop, squash down on the pedal and blow those suckers apart. Like Tester said, go find the dude that did this and beat him about the head and shoulders.

Brakes will always fail with a full load going downhill, that’s why brake failure is always so…exciting.

I wouldn’t even drive that van. Full stop.

I would call my attorney tomorrow morning though, that van is a death trap.

They owe you all of your money back and an apology to boot, followed by your never having them touch any vehicle that belongs to you ever again.

They may balk at giving you your money back but if you take them to small claims court they should be toast if you have the receipt and print out some technical info to take along; such as state laws in regards to this.
You mentioned “inspection”. Does this mean inspect the vehicle or a state licensed inspection station? If the latter, wow.

Ditto what they said. Compression fittings are a no-no on a braking system. I don’t think I would let them work on your van again unless the original work was done by a helper and the owner/chief mechanic is willing to do it himself the correct way (at no charge). And only if he is ASE certified in Brakes.

If they laugh at you and don’t offer a refund or repair, I’d report them to your local licensing authorities or similar. Too many hacks and quacks out there that need to be exposed and excized.

And this “mechanic” is a State Vehicle Inspector??? He will of course swear he never installed the compression fittings.

Did he strip the flare fitting retaining nuts (round them off) and then resort to cutting the lines and using the compression fittings to cover his incompetence?

yes, they are a Massachusetts state licensed inspection station! The owner and his partner (brother I think) both worked on my van together while I waited across the street.

What about all of the other cars these guys have worked on? Am I morally obligated to make sure they don’t keep fixing brake lines this way? Who should I go to to report this?

About this time last year this guy inspected my van and failed me and told me I had to have 3 brake lines replaced and insisted it wasn’t safe to drive. So I paid him, he replaced my brake lines, and passed me. Then, a couple weeks ago, I went down and asked him if he could make me up a short piece that I had to replace and was surprised when he said he didn’t have a double flare tool. I think he uses lengths of pre made double flared steel pipes and cuts them in the middle to make up the right lengths. I will post a photo of that short piece he made me (charged me $35 too!). I Don’t even think he was using a pipe bending tool as it had some sharp curves to it. When I got back… even just looking at the thing as an untrained mechanic, I decided it couldn’t be safe and began to investigate the work he’d done 10 months prior. That’s when I first saw all the compression fittings, but it wasn’t until the strong warning from another mechanic and subsequently looking around online that I realized just how dangerous it really was. I’m concerned because he is a licensed state inspector and I wonder about all of the other brake work he’s done on other vehicles. Also I gave him 300 dollars and still need to replace my brake lines.

I would contact whoever in your state supervises the inspection program and inform them of this. This person needs to go back to Grease Monkey where he belongs…

Installing compression fittings on brake lines is not permissible, that’s all there is to it. I’m retired now, but I held 5 ASE certifications, including brakes, so I’m not just making this up… I’m somewhat surprised the guy was able to find compression fittings that could be used on steel brake tubing. The O.D. of brake tubing usually prevents it.

Does this guy work alone? Other mechanics in his shop should have clued this guy in…

Here’s a good place to start:

First, check the “Information Page” link and then “Auto repair”

Then go back to the original page and scroll down to section 4 and click on the link for “Licensing Page” to see where to file a complaint against a licensed professional.

I would definitely push this and try to get your money back first. If these guys did this to your car then who knows what unsafe things they’ve done to other vehicles, and not just brake lines either.
Suspension parts such as ball joint stud nuts pinned, if at all, with a paper clip or a high pressure fuel line replaced with a “normal” piece of low pressure gas hose. (I’ve seen several examples of both, so it can happen.)

Let’s hold off here a minute.

Are you sure what you’re seeing aren’t compression fittings, but in fact flare fitting couplers? They do look alike. And are perfectly fine for brake line repair.


Yes, I’m pretty sure they are compression fittings, though I guess I can’t know for sure until I disassemble them. This is based off of the fact that I know the mechinic doesn’t have a double flaring tool, and when they made up a short peice of brake line for me they did use a compression fitting that matches exactly what I saw used on my van. Also a real mechanic saw the fittings and was certain they were compression fittings.

they look just like this:

Page 98, last paragraph.,M1

The original inspection may have found a legitimate fault with the brake lines. My 1982 Chevy Van had only one wheel braking (Yeah. Suspence!). Road salts, etc, had rusted the brake lines through. I took the old brake lines off. Straightened them out, went to the auto parts store, and got pre-cut, pre-flared, pre-couplered brake lines off the rack, which were within a couple of inches, in length, of the originals. Put them on easily (no finite calculus involved). The van, then stopped, when I said, “Whoa, Nellie!”! // My question is, “$300 dollars for a cut-and-splice”? Why cobble up the lines, even if the joint couplers are acceptable?

Good “book review”. Good book, Caddyman. I think that every mechanic could use this book in their automotive repair bookcase, seriously.

Thats a compression fitting.

Yeah. That’s a compression fitting.