Rear Brake Line Failed

[MAC]

After I finished replacing the sway bar bushings I decided to manually bleed the front breaks. While depressing the brake pedal it suddenly went to the floor. I could hear what sounded like an air leak and thought I might have blew a master cylinder seal. Well, I pumped on the pedal hoping it was all just a bad dream, but no such luck. So after looking underneath the left rear wheel I could see brake fluid on the ground--it squirted under pressure all the way to the right wheel. I took the left rear tire off and while inspecting I noticed the metal crossover pipe blew a leak. It looks like there are two crossover pipes. The one that blew runs through/on crossover frame support to the right side.

I would appreciate input as to how to fix this problem. Can I buy pre-made brake pipe or do I have to make my own?

[BodybyFisher]

As a matter of fact, I discussed this a few years ago, and have yet to replace it.... not looking forward to it

http://caddyinfo.ipbhost.com/index.php?showtopic=7452

[JimD]

MAC, I would approach this repair carefully.

If your model has four wheel ABS (and I'm betting it does), that means each brake caliper cylinder is independently plumbed all the way back to the ABS module. If one of those lines has corroded that badly, you have to be suspicious of all the brake plumbing.

Sorry I can't help you with the material spec's or the splicing techniques. But you will be dealing with ISO bubble flared fittings.

Make haste slowly.

[MAC]

Thanks for the info. BBF!

Based on what I read from the thread you provided it looks like I might be able to have my local Meineke make the brake line. I'll contact Meineke to find out. Otherwise, maybe I'll just bring the car over to them and have them take care of it. I'll have to make a temp repair to the line so I can get the car over there. If they can replace it for $100 or less then I would rather they deal with it.

[MAC]

MAC, I would approach this repair carefully.

If your model has four wheel ABS (and I'm betting it does), that means each brake caliper cylinder is independently plumbed all the way back to the ABS module. If one of those lines has corroded that badly, you have to be suspicious of all the brake plumbing.

Sorry I can't help you with the material spec's or the splicing techniques. But you will be dealing with ISO bubble flared fittings.

Make haste slowly.

You're right on it, Jim. After inspecting the line from front to rear, it all looks pretty bad. I'm going to see what Meineke says about replacing all of it. I could buy the flaring tool and brake pipe and do it myself, but this would be my first time dealing with this type of job so it's probably best to have the pros handle it. I'm confident that I could do the job but I'm sure it's going to be a P.I.A. for me, plus whatever possible complications I might run into.

[adallak]

MAC, I would approach this repair carefully.

If your model has four wheel ABS (and I'm betting it does), that means each brake caliper cylinder is independently plumbed all the way back to the ABS module. If one of those lines has corroded that badly, you have to be suspicious of all the brake plumbing.

Sorry I can't help you with the material spec's or the splicing techniques. But you will be dealing with ISO bubble flared fittings.

Make haste slowly.

You're right on it, Jim. After inspecting the line from front to rear, it all looks pretty bad. I'm going to see what Meineke says about replacing all of it. I could buy the flaring tool and brake pipe and do it myself, but this would be my first time dealing with this type of job so it's probably best to have the pros handle it. I'm confident that I could do the job but I'm sure it's going to be a P.I.A. for me, plus whatever possible complications I might run into.

I was about to chime in with advice to replace ALL the brake lines right away, but Jim said it already. My brake lines failed one after another within days. When you fix a failed one, the other becomes a weak link in the chain. I would steer clear of Miniken or whatever else. They will charge you alot and will probably insist on unnecessary replacements as well. You better stick with a reputable local mechanic. Just my 0.02.

[MAC]

I'm considering all my options and was wondering if I can use any ISO flaring tool to make the bubble flares? GM's Factory Service Manual calls for a specific ISO flaring tool but I would imagine that any ISO tool will do the job. The tool recommended by the Manual is over $250.

Also, is the rear crossover line 3/16"? I just want to make sure in case the Meineke option doesn't happen.

[MAC]

I was about to chime in with advice to replace ALL the brake lines right away, but Jim said it already. My brake lines failed one after another within days. When you fix a failed one, the other becomes a weak link in the chain. I would steer clear of Miniken or whatever else. They will charge you alot and will probably insist on unnecessary replacements as well. You better stick with a reputable local mechanic. Just my 0.02.

I figure you're right about Meineke. I don't know any local shop that will do this work. I'm going to have to make some phone calls. I'm trying to gather all the info regarding doing the job myself because all the piping from front to rear needs to be replaced.

[adallak]

Any parts store sells flaring tools which usually do all the types of flaring. The tool is about $30.00. Believe me the flaring is probably the easiest part of the job...

[KHE]

I'm considering all my options and was wondering if I can use any ISO flaring tool to make the bubble flares? GM's Factory Service Manual calls for a specific ISO flaring tool but I would imagine that any ISO tool will do the job. The tool recommended by the Manual is over $250.

Also, is the rear crossover line 3/16"? I just want to make sure in case the Meineke option doesn't happen.

I believe any ISO flaring tool will produce the same flare as the tool in the GM shop manual. The tools specified in the shop manuals are all distributed by Kent-Moore. They are HORRIBLY expensive - one such example is the pulley puller for the waterpump pulley that is mounted on the end of the front cam. The Kent-Moore tool was well over $100 but it was identical to a power steering pulley puller that I bought for $20 at the local auto parts store...

[joeb]

the line for the driver side rear wheel rusted thru on my grand prix and the previous owner had some type of pressure compensating device put in. its only on one wheel so i can't see it being some type of proportioning valve. Its the size of a bic lighter and has threaded connections on each end. is it supposed to even be there? i might check the boneyard for similar aged cars and see what those lines look like. might find a non-rusted line.

[PAUL T]

I had replaced some lines on my 94 Deville as well as numerous other vehicles and it is not a big deal. What I did is just take the old line out and measure it, then go buy a line at the parts place that is closest to the size and length you need. They come pre made with fittings on both ends, then bend it by hand to a shape that is similar to the old line and re-attach and bleed. The biggest problem will be getting the old fittings loose. A little WD40 or equivalent will help. Also a good set of line wrenches help. If you are afraid of kinking the line by hand, the tube benders are pretty cheap. If it is a little long a few extra bends will not hurt anything. Now some of you all will think that is terrible if you don't have it looking just like the old line but as long as you get it in about the same shape it will not make a difference. Unless you are planning on showing it in a car show where you are judged on the undercarriage no one will notice.

[Ranger]

The tools specified in the shop manuals are all distributed by Kent-Moore. They are HORRIBLY expensive

AKA Spent-More.

Glad you where not driving it at the time this happened.

[MAC]

Thanks for the input KHE & Paul T. Upon further inspection I found that it's the line from the engine compartment that popped a hole. I located the hole and I'm in the process of patching it until I can order a role of 3/16 flex tube, which I believe should do the job. I also need to order brake line nuts. I found a 25-foot roll of corrosion proof brake line being sold by Federal Hill Trading Company in MA.

I take it the nuts are Metric since it's 12mm--at least I use a 12mm wrench?

[Ranger]

Mac, I cannot imagine any patch you could put on it that would withstand the pressure when you step on the brake pedal. I would not recommend driving it like that. Imagine stepping on the brakes and having the pedal go to the floor. Talk about a "sinking" feeling. (Pun intended)

[WarrenJ]

Mac, I cannot imagine any patch you could put on it that would withstand the pressure when you step on the brake pedal. I would not recommend driving it like that. Imagine stepping on the brakes and having the pedal go to the floor. Talk about a "sinking" feeling. (Pun intended)

It was probably a third of a century ago I lost the brakes on my '71 TR-6. I was doing 50 mph on the local turnpike (Hempstead Tnpk. in Uniondale for BbF). PANIC!!

I yanked the Emergency Brake lever in the console and promptly locked up the rear wheels!

Now you can't do that today. Maybe that's why what we once knew as "Emergency Brakes" are now called "Parking Brakes."

Regards,

Warren

[adallak]

Mac, I cannot imagine any patch you could put on it that would withstand the pressure when you step on the brake pedal. I would not recommend driving it like that. Imagine stepping on the brakes and having the pedal go to the floor. Talk about a "sinking" feeling. (Pun intended)

It was probably a third of a century ago I lost the brakes on my '71 TR-6. I was doing 50 mph on the local turnpike (Hempstead Tnpk. in Uniondale for BbF). PANIC!!

I yanked the Emergency Brake lever in the console and promptly locked up the rear wheels!

Now you can't do that today. Maybe that's why what we once knew as "Emergency Brakes" are now called "Parking Brakes."

Regards,

Warren

You can do that, but you have to shift to neutral. Do not ask how I have learned that...

[steve6]

I'm considering all my options and was wondering if I can use any ISO flaring tool to make the bubble flares? GM's Factory Service Manual calls for a specific ISO flaring tool but I would imagine that any ISO tool will do the job. The tool recommended by the Manual is over $250.

Also, is the rear crossover line 3/16"? I just want to make sure in case the Meineke option doesn't happen.

Is this for your '94? any auto parts store will sell a barage of different lenghts and flares... Just take off the line from where it screws in at one and and the same at the other.. get the distance and take the ends with you and goto the Auto Parts store and match a couple pieces together so its near the right length, and you can get adapters for the flares if they dont have the right lines on the lines themselves... If you get a couple inches too long, make a couple loops.. whats the difference -its a 94 you'll probably be the last owner... Worried about doing the bends? use the box'd end of a wrech to make bends, helps pull the line easier than trying to do it with your hands.. just dont kink anything.

You do not need to get fancy on a 94.. I've replaced dozens of brake lines, never used a flaring tool....

[MAC]

I'm considering all my options and was wondering if I can use any ISO flaring tool to make the bubble flares? GM's Factory Service Manual calls for a specific ISO flaring tool but I would imagine that any ISO tool will do the job. The tool recommended by the Manual is over $250.

Also, is the rear crossover line 3/16"? I just want to make sure in case the Meineke option doesn't happen.

Is this for your '94? any auto parts store will sell a barage of different lenghts and flares... Just take off the line from where it screws in at one and and the same at the other.. get the distance and take the ends with you and goto the Auto Parts store and match a couple pieces together so its near the right length, and you can get adapters for the flares if they dont have the right lines on the lines themselves... If you get a couple inches too long, make a couple loops.. whats the difference -its a 94 you'll probably be the last owner... Worried about doing the bends? use the box'd end of a wrech to make bends, helps pull the line easier than trying to do it with your hands.. just dont kink anything.

You do not need to get fancy on a 94.. I've replaced dozens of brake lines, never used a flaring tool....

Today I bought a 25-foot roll of 3/16 brake line at Napa because the both lines are just too rusted to try to splice it. From right below the master cylinder where it's exposed to the underbody is where the rust begins.

It took me until 3:30 today to get all the parts together. The brake line nuts are metric for the ISO bubble flare--you can put a 12mm box wrench on the nut. Autozone had 4-foot lengths of exactly what I needed to splice into the line, but after it became apparent that no splicing could be done, I scrapped that idea. Actually, I bought two from Autozone because in case the splice didn't work I could always use the nuts with the 25-foot roll. I also bought a OTC 4504 - Stinger Bubble (I.S.O.) Flaring Tool Kit at Napa for $31. I made a practice flare and it does a nice job. I'm going to have to do this job during the week (if possible after work) and/or over this coming weekend. In the meantime, I'm renting a car, which I don't want to do, but I have to because I don't want to take another day off for a car problem. I'll suck it up to experience and go from there.

If I had known about the potential for this situation (I should have inspected my brake line more closely) I would have made sure I had all the tools and parts purchased ahead of time instead of scrambling to locate everything, which wasted a lot of valuable time. I'm not experienced with brake line replacement so I had to figure out which parts to buy and where to go to get them.

By the way, one of my concerns was the short rubber crossover hose, which is located on the left side rear with one end attached to a bracket with a metal line from the proportioning valve feeding into it and the other end attaches to the crossover pipe. Anyway, I went to buy it at a Cadillac dealership and was told by the parts person that I was not available. He then gave me a part number and claimed some company bought all of GM's parts and that I should call the phone number he gave me to see if it was available. So I left thinking whoever these people are they will probably charge me an arm and a leg for it. So, I checked out the possibility of having one custom made. Then I thought I would try another Cadillac dealership where I usually go to buy parts. Wouldn't you know it but the part was available for a mere $18. In fact, the guy was nice enough to make a call and get it to me this afternoon. So why was I given the run around by the other Cadillac dealership?

[MAC]

I finished replacing all the brake lines for the rear brakes. There are two lines going to the rear brakes. One of them I replaced from the engine compartment proportioning valve and the other I cut about a foot back from the fire wall and used a coupler to splice in new line. I used at least 20 feet of pipe.

It was a difficult job because I didn't have a lift and I'm a novice at doing this kind of repair. It was difficult to get the angles and room needed to get at brake line nuts. Also, the fuel line runs along with the brake line so I had to remove it all and then re-hang it like original. I wouldn't want to do this repair again without a lift. I had to bleed the brakes twice because the pedal still didn't feel right after the first bleed. After the second, the brakes are back to normal.

[Texas Jim]

Good job. Glad you got it all fixed up.