brake line question

18 years ago

our '85 olds 88 runs like a champ and just turned 100k miles. I replaced the front brake pads yesterday as they were down to about 1/8", and the brakes are now more responsive. While changing them I noticed two cracks in the top of the rubber brake line where it connects to a metal line and disappears up into the engine area (only the 12 inches or so of the line closest to the caliper is rubber - I assume that is normal). The brakes have never leaked or lost fluid. Is this a problem? The crack appears to be on the outer housing of the line and there must be an inner line as well or surely they would have leaked long ago. Thanks.

Comments (2)

john_g
18 years ago
Once the outer housing cracks, the inner layers are exposed to the elements and will fail rather quickly, as well as the inner layers have lost the support that the outer layer is designed to give, which will promote more flexing at those points and increase the rate at which ths hose will fail.

So, a cracked outer layer on a brake hose means it is replacement time, right now! It is good that you noticed this, and asked the question. At the same time, this is one of the differences between doing something as simple as brakes yourself, or taking it to someone that does it for a living. Had you ignored this condition, it would eventually have resulted in a failure, and all bets would be off on what the outcome of that would have been.

Now for the bad news,,, a 1985? You will need to replace the steel lines all the way to the master cylinder in order to ensure the system has been restored completely. Left undisturbed, the steel lines may do their job indefinately. But the stress of replacing the brake hose will hasten their ultimate demise (If they even come apart in the first place). Good luck with this. I'd be cringing at the prospect of potentially having to replace every single line on the car (brake and fuel) simply because of watching leaks occur as they get manipulated during replacement of other lines in the car.
duanejack
18 years ago
I recommend by no special rules that rubber components (hoses) be changed every 10 years and metal components every 15 (lines) in this area. This comes from visual inspection only and inspecting many thousands of these things over the last 10 years in my area. There is a safety inspection here and the rubber hoses will usually fail between 10 and 12 years by default. If you are going to change more than one piece then I recommend bleeding each corner (individual wheel area) as you go. For example you change the rubber and metal on the left front first, then bleed it and do the right front last and bleed it. Without special equipment to insure a good job I recommend that you do it the ole fashioned way and keep it simple by doing them one at a time with a friend. If you plan on doing the rears then do them first. Yes this takes more bleeding but less of a chance of not being able to bleed at all with all four corners completely empty. Use what brake fluid you need and then properly dispose of the rest at your local hazardous drop station, dont keep an opened brake fluid jug on the shelf, it will go bad in time.

Have you heard of the umbrella trick between the seat and the brake pedal, keep the brake pedal depressed (past the internal vents) to keep the entire reservior from draining while you are working. Good luck

Duane in Japan
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brake line question

Comments (2)

john_g

duanejack

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