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extended rubber brake lines?

Posted: Tue Mar 31, 2009 7:21 pm
by 60_series_united
hey guy made my rear brake line longer today just joined another one into it (i know its illegal) and now the brake peddle is alot softer ? is it just because of the rubber expanding? there is no air in the system.
thanks tyson

Re: extended rubber brake lines?

Posted: Tue Mar 31, 2009 7:35 pm
by bogged
Get a braided line made up, will be 100.. will be legal and wont fuck up and kill someone.

Re: extended rubber brake lines?

Posted: Tue Mar 31, 2009 7:47 pm
by 60_series_united
bogged wrote:Get a braided line made up, will be 100.. will be legal and wont . up and kill someone.
not worried about legal nothing else is, how would i kill someone there is no more pressure in the line

Re: extended rubber brake lines?

Posted: Tue Mar 31, 2009 7:56 pm
by Gwagensteve
*ahem*
peddle is alot softer ?
That's why.


A soft pedal will mean you will run out of pedal travel before the SAME pressure is reached in the system.

You now have less effective brakes. That's why you need to sort the problem out.

Steve.

Posted: Tue Mar 31, 2009 7:59 pm
by Rhett
one line shouldn't have softened up the pedle you must have air in it still.

Re: extended rubber brake lines?

Posted: Tue Mar 31, 2009 8:07 pm
by 60_series_united
Gwagensteve wrote:*ahem*
peddle is alot softer ?
That's why.


A soft pedal will mean you will run out of pedal travel before the SAME pressure is reached in the system.

You now have less effective brakes. That's why you need to sort the problem out.

Steve.
they still work fine, i dont need to pump them or anything like that they still lock up
one line shouldn't have softened up the pedle you must have air in it still.
there is no air in it.

Posted: Tue Mar 31, 2009 8:38 pm
by mike_nofx
It would probably be too long, instead of adding a few inches you have doubled its length... Get one made up.
I got 3 made up at a brake shop for $45 each.

Posted: Tue Mar 31, 2009 8:51 pm
by 60_series_united
mike_nofx wrote:It would probably be too long, instead of adding a few inches you have doubled its length... Get one made up.
I got 3 made up at a brake shop for $45 each.
thanks mate ill look into it, once i get the suspension done ill get something the length i need

Re: extended rubber brake lines?

Posted: Tue Mar 31, 2009 9:00 pm
by bogged
60_series_united wrote:
bogged wrote:Get a braided line made up, will be 100.. will be legal and wont . up and kill someone.
not worried about legal nothing else is, how would i kill someone there is no more pressure in the line
Theres a difference in "nothing legal" with oversized tires, and brakes shitting themselves and you killing someone.

Re: extended rubber brake lines?

Posted: Tue Mar 31, 2009 9:16 pm
by 60_series_united
[[/quote]Theres a difference in "nothing legal" with oversized tires, and brakes shitting themselves and you killing someone.[/quote] my brake arnt goin to f**k up they work just as well as they did before i was just wondering if it was the rubber line expanding that is causing my pedal to be softer

Posted: Tue Mar 31, 2009 9:42 pm
by Gwagensteve
I really don't want to harp on this, but a soft pedal means less available braking force. They might still lock up, they might still work, but they are just not working as well.

Assuming you made NO other changes when the extension was fitted, you either have air in the system, ( which apparently is impossible) or you have a significant amount of hose expansion.

Sorry, that's a problem.

If you don't think it is a problem, you're wrong. I've fitted all sorts of extended lines to all sorts of cars and haven't had a problem with long lines causing a soft pedal.

If you don't care, then that's fine, but don't blame us for trying to tell you.

Steve.

Re: extended rubber brake lines?

Posted: Tue Mar 31, 2009 9:43 pm
by Shadow
bogged wrote:
60_series_united wrote:
bogged wrote:Get a braided line made up, will be 100.. will be legal and wont . up and kill someone.
not worried about legal nothing else is, how would i kill someone there is no more pressure in the line
Theres a difference in "nothing legal" with oversized tires, and brakes shitting themselves and you killing someone.
if the lines are both in good condition i cannot see it being a point of failure.

yes, more pedal travel is required, but if he still has pedal travel available, and enough pressure to lock up his brakes, i cant see it being dangerouse.

I also wonder what makes joining two rubber hoses together illegal. They are both hydraulic hoses rated for the job.

Re: extended rubber brake lines?

Posted: Tue Mar 31, 2009 9:50 pm
by Gwagensteve
Shadow wrote: but if he still has pedal travel available,
I wasn't making a comment about legality or whether it was dangerous, but that's my concern. Potentially having the pedal hit the firewall because there was more pedal travel before the required pressure was achieved is a concern and shouldn't be the case with the addition of ONE longer brake line.

To me that indicates a fault, regardless of whether it's currently dangerous or not.

Steve.

Posted: Tue Mar 31, 2009 10:53 pm
by BlueSuzy
got 2 made up for $35 Each.

Shop around dude. Theres alot of things that are more pricey on a 4wd. But this is money well spent and cheap.

Re: extended rubber brake lines?

Posted: Wed Apr 01, 2009 6:58 am
by GU_247
60_series_united wrote:
bogged wrote:Get a braided line made up, will be 100.. will be legal and wont . up and kill someone.
not worried about legal nothing else is, how would i kill someone there is no more pressure in the line
Another f@#$wit that doesnt care about giving everyone else in the 4wd scene a bad name. why dont you spend the extra dollars and make it safer. Also extended lines should be braided to eliminate expansion that causes the softer pedal.Its not under normal braking you should be woried about. Its in an emergency one your fluid is starting to get heated up

Re: extended rubber brake lines?

Posted: Wed Apr 01, 2009 7:40 pm
by 60_series_united
Gwagensteve wrote:
Shadow wrote: but if he still has pedal travel available,
Potentially having the pedal hit the firewall because there was more pedal travel..
its not goin to hit the firewall, drove to work today its good, i didnt notice any difference while driving it. the pedal is still hard i just have to push it bout 1" or so further

Re: extended rubber brake lines?

Posted: Wed Apr 01, 2009 7:54 pm
by 60_series_united
Another f@#$wit that doesnt care about giving everyone else in the 4wd scene a bad name.
im not giving anyone a bad name its people that bitch about others modifying there cars

Posted: Wed Apr 01, 2009 8:00 pm
by Gwagensteve
I give up.


Your brakes are even better now than they were before. Make the hose even longer. It will stop even better.

Steve

Posted: Wed Apr 01, 2009 8:07 pm
by hudson44
Is it proper hydraulic braided brake hose you have used or is it some dodgy non rated hose with a couple of hose clamps type back yard repair? If the brake line is "bulging" then this is an issue. Yes, at the moment the pedal is fine. But what happens when the hose becomes fatigued from expanding and starts to leak, running your reservoir down and when you're on your way to work and the Sunday driver in front of you hits their brakes to have a look at the pretty houses and because you have no fluid left the pedal hits the floor. You would be quite surprised how much hydraulic pressure is in those lines in an emergency!

Plain and simple, a descent brake line should not flex or bulge. Hydraulic pressure is equal in all directions, so you could have a flexible hose that runs the length of your car and providing its rated there will be the same amount of force applied at the caliper or wheel cylinder.

Posted: Thu Apr 02, 2009 5:59 am
by KiwiBacon
BlueSuzy wrote:got 2 made up for $35 Each.

Shop around dude. Theres alot of things that are more pricey on a 4wd. But this is money well spent and cheap.
I got some made up for roughly the same price (adjust for the NZ peso and it's right there). Comes in a bag stating they meet the SAE standards etc, have a plastic coil around them to ward off chaffing.
As for "braided line", you'll find all brake lines are braided. Some just have a rubber cover so the braids aren't exposed.

It amazes me how people will happily spend thousands on wheels and tyres and begrudge anything they have to spend on brakes. :roll:

Posted: Thu Apr 02, 2009 7:22 am
by Shadow
hudson44 wrote:Is it proper hydraulic braided brake hose you have used or is it some dodgy non rated hose with a couple of hose clamps type back yard repair? If the brake line is "bulging" then this is an issue. Yes, at the moment the pedal is fine. But what happens when the hose becomes fatigued from expanding and starts to leak, running your reservoir down and when you're on your way to work and the Sunday driver in front of you hits their brakes to have a look at the pretty houses and because you have no fluid left the pedal hits the floor. You would be quite surprised how much hydraulic pressure is in those lines in an emergency!

Plain and simple, a descent brake line should not flex or bulge. Hydraulic pressure is equal in all directions, so you could have a flexible hose that runs the length of your car and providing its rated there will be the same amount of force applied at the caliper or wheel cylinder.
if you read what he wrote, he used 2 standard brake lines, screwed them together, and used them (they have a male thread one end, female thread the other).

So yes, they are rated brake lines, rated for the use in an automotive brake system and will employ a nylon braid inside the rubber.

Yes, you could have flexible hose 100m long, and if you put 100ft/lb's of pressure at the master cylinder, youd get 100ft/lb's of pressure at the brake cylinders.

That is not the issue at all. The issue is, that a flexible brake line has a small amount of expansion, this is an unfortunate part of being flexible. So the longer the flexible hose, the more Fluid that must be moved to achieve said pressure, as the tube expands, more fluid flows etc. Thus, eventually your master is too small, and you run out of stroke.

Alot of people are being anal in this thread and I think either havent read the thread, or just want an excuse to have a go at someone.

There are much more dodgy things done on modified 4wd's than using 2 rated brake lines instead of one. Theres photos on here of people who have welded steering shafts, and used fencing wire for steering so they could get home (pity if the wire gave way on the way home and you just happened to crash through a preschool).

A softer pedal does not mean its not safe. If the hoses are rated for use in a brake system, which they are, the hoses are in good condition, and he can still achieve "sufficient pressure" at all brake cylinders, then I see no problem with what he has done, nor do I see how what he has done is illegal, anyone care to point out what makes it illegal?

If it is simply that he has modified his brake system, that makies it illegal, then any extended brake line is in the same situation. Wether its 10mm longer or 10m longer.

"sufficent pressure" would mean what is deemed safe by the governing authorities. (or as specified in the factory service manual)

I just had a safety certificate done on a 100series which apparently got 76% braking capacity, (they probably just made that up IMO), but apparently that is safe.

Posted: Thu Apr 02, 2009 7:52 am
by KiwiBacon
Shadow wrote:if you read what he wrote, he used 2 standard brake lines, screwed them together, and used them (they have a male thread one end, female thread the other).

So yes, they are rated brake lines, rated for the use in an automotive brake system and will employ a nylon braid inside the rubber.

Yes, you could have flexible hose 100m long, and if you put 100ft/lb's of pressure at the master cylinder, youd get 100ft/lb's of pressure at the brake cylinders.

That is not the issue at all. The issue is, that a flexible brake line has a small amount of expansion, this is an unfortunate part of being flexible. So the longer the flexible hose, the more Fluid that must be moved to achieve said pressure, as the tube expands, more fluid flows etc. Thus, eventually your master is too small, and you run out of stroke.

Alot of people are being anal in this thread and I think either havent read the thread, or just want an excuse to have a go at someone.

There are much more dodgy things done on modified 4wd's than using 2 rated brake lines instead of one. Theres photos on here of people who have welded steering shafts, and used fencing wire for steering so they could get home (pity if the wire gave way on the way home and you just happened to crash through a preschool).

A softer pedal does not mean its not safe. If the hoses are rated for use in a brake system, which they are, the hoses are in good condition, and he can still achieve "sufficient pressure" at all brake cylinders, then I see no problem with what he has done, nor do I see how what he has done is illegal, anyone care to point out what makes it illegal?

If it is simply that he has modified his brake system, that makies it illegal, then any extended brake line is in the same situation. Wether its 10mm longer or 10m longer.

"sufficent pressure" would mean what is deemed safe by the governing authorities. (or as specified in the factory service manual)

I just had a safety certificate done on a 100series which apparently got 76% braking capacity, (they probably just made that up IMO), but apparently that is safe.
The only time I have had a spongey brake pedal (when I know air is not the problem), it was traced to a damaged brake line. Swelling enough to feel spongey to the pedal.
Replaced it with new ones and bingo, hard pedal.

The original poster has spongey brakes after fitting an extra line, to me that suggests the line which was fitted has a problem and should be replaced.
Or, as has been suggested, air is in the system.

Either way, it's not really fit to be driven.

Posted: Thu Apr 02, 2009 11:18 am
by hudson44
Shadow wrote:if you read what he wrote, he used 2 standard brake lines, screwed them together, and used them (they have a male thread one end, female thread the other).
Thats why i asked the question as to how he went about the "modification" to the brake line as nowhere does he state that a rated hose was used or not. If there is no air in the system, as he strongly states and the pedal is worse then there is an issue. If the hose is bulging, as he stated then this is an issue and unroadworthy. The hose may be fine and the master may have sh!t itself while bleeding the system. Its very hard to comment on what the issue may be without seeing the vehicle and the "mod" to the brake line. My suggestion is to stop being a tight arse and take it to a qualified mechanic and have it repaired properly.

Posted: Thu Apr 02, 2009 12:28 pm
by TWISTY
My 40 has two std. lines joined both on the front and rear to extend them. Didn't notice any difference in braking or pedal pressure when done. Was done as a temp fix to get it drivable again after suspension mods but have never gotten around to getting new ones made. Will do someday. Cant see it being much of a problem either way but as some others have said.

If your pedel did get softer when adding the extra hose it's obvisouly got something wrong with it. Try swapping out the extra hose you put in for another and see if that fixes it.

Posted: Fri Apr 03, 2009 1:55 pm
by mavzilla
answer ,yes it will loose a small margin of pedal but still work fine, enjoy the chity chat

Posted: Sat Apr 04, 2009 1:52 pm
by 60_series_united
The original poster has spongey brakes after fitting an extra line, to me that suggests the line which was fitted has a problem and should be replaced.
Or, as has been suggested, air is in the system.

Either way, it's not really fit to be driven
i never said i had "spongey" breakes i just said the pedel was softer after fiting the line, it is still hard if i push right down on it, i bled the system and i am not getting any air so im sure there is none in the system

Posted: Sat Apr 04, 2009 1:54 pm
by 60_series_united
TWISTY wrote:My 40 has two std. lines joined both on the front and rear to extend them. Didn't notice any difference in braking or pedal pressure when done. Was done as a temp fix to get it drivable again after suspension mods but have never gotten around to getting new ones made. Will do someday. Cant see it being much of a problem either way but as some others have said.

If your pedel did get softer when adding the extra hose it's obvisouly got something wrong with it. Try swapping out the extra hose you put in for another and see if that fixes it.
yeah im only using this till i get my suspension done so i can get the right length line made i dont want to spend $100 on a line that is too short

Posted: Sun Apr 05, 2009 7:43 am
by GU_247
hudson44 wrote:
Plain and simple, a descent brake line should not flex or bulge. Hydraulic pressure is equal in all directions, so you could have a flexible hose that runs the length of your car and providing its rated there will be the same amount of force applied at the caliper or wheel cylinder.
To a degree this is correct but you do get a small difference when running thru flexible lines as the rubber in the lines will compress slightly against the braid...might not be much bit it definitely does. Hence why most extended lines are S.S braid with a teflon lining

Posted: Sun Apr 05, 2009 10:17 am
by ferrit
i paid $80 each for 700mm long, braided steel lines, with fully legal crimped on fittings.

brake lines

Posted: Sun Apr 05, 2009 7:37 pm
by 60_series_united
do anyone actually know why joining 2 lines is illegal?