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14 year old insights and rusted brake and gas lines

54K views 174 replies 64 participants last post by  joeaax1j 
#1 ·
My green 2000 lost its brakes yesterday. Went to the town hall to pay the taxes, and as I came to the final stop in the parking spot, the brakes went to the floor.
The silver 2000 did the same thing last year, at the end of my driveway. In both cases there was no brakes at all, except for the emergency brake.
As our fleet of cars gets close to 15 years old, this sudden loss of brakes could be very dangerous. I am ordering a set of factory brake lines from Majestic Honda, and was thinking of installing them during the meet.
Since I still have 2 more 14 year old Insights that could use brake lines and possibly gas line replacement, I was wondering if making up stainless lines and fittings would be a better option.
Has anyone explored this?
This is a serious safety issue, as the lines just let go, and the brakes just stop working.
Would not want this to happen on the highway or when a sudden stop is required, and it seems that this is a problem that will continue to get more likely as our cars get older.
I want my Insights to last at least another 10-15 years if possible.
 
#3 ·
Nope, it was the steel line that had lost the integrety of the plastic break line covering in both cars. The green one was on the passenger rear, and the silver one was right at the clamp that supports the steel line to the rear of the passenger front tire. Looks like sand gets kicked up on the lines and clamps, and vibration of the sand covered clamp abrades the outer plastic until a path for moisture develops.
Have not got under it yet to take any photos.
 
#4 ·
Just done mine last year as they came up as advisorys on the MoT and then this year failed due to excessive corrosion. Garage replaced the runs with copper lines.

MoT = Ministry of Transport test all cars have every year in the UK (onces its more than 3 years old). Guess this is a perfect example of why they are useful.

Always seems to be where the clips are.
 
#5 ·
copper lines sound like a good fix, much easier to bend then Stainless.
The problem I ran into last year when the other car lost a line was to find the end fittings.
I ended up cutting the line where it was broken, and put a splice fitting. It has been holding up, but Now that I have lost my brakes twice, I am looking for a better fix that I can trust for another 14 years.
Found this
Thread Identification for Brake Lines
Does anyone know what the correct fitting is, and a source?
 
#63 ·
Does anyone know what the correct fitting is, and a source?
Yes. It's a bit of a bastard. Metric M10 x 1.0 threads, but threaded all the way to the end of the nut for a SAE double flare. Standard ISO bubble flare nuts with the same thread will work, but you will need to grind off the unthreaded lead.

They can be purchased here:

3/16"/4.75mm Metric thread brake line nuts and fittings

Either the #18 or #22 Nut Pack will work. The only difference between the two is the length of the nuts (16 mm vs 21 mm).
 
#6 · (Edited)
I presume the copper mentioned is for the gas lines. I use stainless for my brakes whenever I refurb a car. Its really not bad to work with. A small tubing bender works well. You do want to use double walled tubing though as well as double flare all the fittings (this applies to steel as well). Line psi can reach into the 1000s of psi (not a typo). The one little thing you dont want to over look is isolating the stainless from any metal brackets. I use small rubber bushings and slide them on the line and clamp around that bushing. Stainless lines can look like artwork if you take your time bending them-i love em!
As far as threads, IIRC most stuff is Metric fine thread now. Older stuff was NPF thread. I dont think ive ever ran across imp thread.
The fittings can be found at any parts place. Bring a piece of line (for size) or the old fitting and they should have them in stock
 
#8 · (Edited)
wow! napa didnt have them, they would have been my first pick. If you have to, you could buy the smallest repair sections they have and cut those to scavange the fittings that way.
I just thought of this-regular fittings is what i was thinking of. If your looking for those to be in stainless as well then yeah, they prob dont have them. Ive got a book lying around here someplace that has them. Ill try to find that. You can use reg steel fittings though with the stainless. Ive had no issues doing that in the past.

here is a place I use often. Prob best to callfor exactly what you need but they have loads of stuff in stainless http://www.classictube.com/index.php
 
#9 ·
..... In both cases there was no brakes at all, except for the emergency brake......
Mike,

I'm glad your OK. That sounds scary to say the least.

I thought that all cars had a "primary" and "secondary" side to the master cylinder, such if you lost fluid pressure to the front brakes (primary side) that the rear brakes would still work (secondary side).

Puzzled? :(

Jim.
 
#10 ·
Every time it rains my brakes seem to get a slight surface rust on them, impacts my MPG a few MPG or so. Once the roads are dry I roll to a stop, then at a few MPG stomp on the brakes, and only when there is no cross traffic coming. Hopefully continuing to do that will cause the brake line to pop then and not somewhere else when it counts. Normally I brake early and lightly to get as much regen as possible. I hate it when I actually start using the brake pads to stop.....

Like 3 wheeler said, I thought there was two halves to your brakes and you could lose the front or rear and still stop....
 
#11 · (Edited)
Ditto on the "glad you're ok". That could've ended much differently.

biododge makes a very good point about pressure. In an emergency stop, stomping on a pedal runs hydraulic pressure up pretty high (even with abs). Pressure rating and wall thickness is a big consideration. I don't know what the pressure rating is for copper, but being a 'soft metal' , I don't think it's high enough for hydraulic brakes, especially if it's thin wall, to withstand sudden high pressure. And after bending, the 'outside radius' of a bend will be even thinner and weaker.

I'd go with stainless with a high pressure rating.

another 2 cents worth.
 
#15 · (Edited)
Ditto on the "glad you're ok". That could've ended much differently.

biododge makes a very good point about pressure. In an emergency stop, stomping on a pedal runs hydraulic pressure up pretty high (even with abs). Pressure rating and wall thickness is a big consideration. I don't know what the pressure rating is for copper, but being a 'soft metal' , I don't think it's high enough for hydraulic brakes, especially if it's thin wall, to withstand sudden high pressure. And after bending, the 'outside radius' of a bend will be even thinner and weaker.

I'd go with stainless with a high pressure rating.

another 2 cents worth.
This site is a crazy place sometimes - stuff like that above cited as fact. Try bending one of those 2 cents you have next time you use them?

Copper nickel has been used by OEMs since the start of time for automotive brake systems - certainly in Europe, painted steel has taken over purely due to its cost benefit as obviously the poorer corrosion. The fact its 'soft' works for you when forming swages and getting the pipe to actually seal!

Never seen a stainless brake kit part tbh, copper IS the auto standard. Stainless is just racer/ricer bling.
 
#12 ·
most systems are a 2 sided design. They use a 'X" configuration. to control 1 front brake and 1 rear (to maintain stability). These are split (kind of) in the master. The issue lies inside the master where both cup seals need psi from each other to keep brakes functional. Once 1 side looses psi (after a few pumps) they both stop working. The real kicker is the combo valve is supposed to shut off the leaky side to maintain psi (internal sliding valve) but ive never had one work correctly...Ever.
 
#13 ·
I was surprised that the brakes failed completely as I assumed it should have redundancy.
Bottom line, I think we should put all the insights on a lift and inspect the brake lines at the up coming NE Hybrid meet since Paul is generous enough to let us have access to his lift we could have an assembly line, take off the covers, inspect lines, and reinstall the covers, or the new aluminum covers.
The brake parts I intend to order are ~ $200 and this is most of the lines and flex hoses. Probably should just get new hangers as well.
I will know what the availability i when I order them, and may order more than one set?


Most of the corrosion is right at the clamps, or on the end fitting area, where the steel is exposed, so with a new line, one could paint those areas with an undercoating to prevent rust of the bare steel, and the lines may last much longer?
 
#14 ·
I was just under my car a month ago and the lines are totally covered in exposed, flaking rust (like old iron pipes). Weird as everything else underneath looks great. Once you get the parts could you post the PN's and price needed to change them out.
 
#16 ·
I am not too concerned with the cost of the new factory lines, and if corrosion protected with some undercoating or paint while still new, should go another 14 years.
Small diameter copper tube is used for refrigeration, and can withstand lots of internal pressure, but then I would need to deal with the double flange and finding fittings.
 
#18 ·
Hybrid brake line

In the past I have purchased the shortest steel unpainted brake lines at a parts store and cut off the fitting ends about 2" long and telescoped into soft copper refrigerator tubing about 1" and soft (lead/tin) soldered in place being sure that the steel brake tubing was well tinned before assembly. I have never pressure tested this type of assembly but have seen no problems after over ten years of use. The copper tubing needs to be supported at shorter intervals than the OEM steel tubing.

It is my understanding that steel brake lines are in cross section a coil of copper brazed steel and are not cold drawn seamless tubing. It is this construction of two dissimilar metals that produces galvanic action that leads to more rapid corrosion than would be expected.
 
#19 ·
Fittings

Hi Mike,

Were you able to resolve what the fitting dimensions were? Or is your plan now to simply go with stock lines from Majestic?

I'm assuming their standard metric brake line fittings like I've had on other Honda cars historically.

If nobody has figured this out, I plan on doing so in Sept when I have time off.



Greg
 
#20 ·
I have 3 - 2000 insights, and after having two of them fail for the same thing.
Was lucky I was going very slow both times, or things could have been much different.
I figure I will start with a complete set of new lines, identify the fittings, measure and document the bends and lengths of each piece on a CAD drawing so we will have it captured.After doing it once, I can decide what to do with the other 2 Insights.

From what I have seen so far, the tube is fine as long as the outer plastic sheath is intact. The ends have about 3/8 " right before the fitting where there is bare metal, and that is where the major corrosion is taking place,as well as in the clips where the outer plastic has been compromised. We are hitting the fittings with PB blaster or WD40, every day to try to free them up before we try and remove them.
I should have the parts by Saturday.
 
#21 ·
Brake line wrench

There is a special kind of wrench made for brake line work. It is a thick six sided open end wrench where the open end is reduced to a slot just wide enough to slip over the tubing which is where the extra sixth side grip is located. If you attempt to break loose badly corroded fittings using a conventional open end wrench, you may round away the fragile corners of a corroded fitting and wind up having to use vise grips or worse.

Avoid the grief and be prepared with the right tool.
 
#25 ·
I also have a 2000 Insight but I live in Southern California where there is very little ice/snow (Yes I've seen some frost in the Winter with Climate change) where I live. Do you expect this to be a problem with Insights in areas devoid of snow and the salt that's used to deice the roadways? Since you believe it's the sand that lead to the corrosion, would a simple application of
underbody coating applied to the brake and gas lines protect them from possible corrosion in mild climate areas like Southern California. Or do you think it's wise to just replace the lines with stainless steel to be on the safe side?
 
#26 ·
As much as I love the stainless, for your area it would be overkill. I would just inspect, and repair (repaint/epoxy ect) any bad spots. The reason i use stainless is from all the salt used here. Ive a old plow truck that would get eaten alive every few yrs. After a bout 5 diff times of the trans or brakes rupturing I switched to SS and have yet to touch them. The lines on my dads ol truck are 20yrs old and still look (almost) new and its a headache ill never have again repair wise.
 
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