just replaced all my brake lines .....never again!

[xxxscimitarxxx]

last year l was poking around (always a bad thing to do) and saw some corrosion on the brake pipes as they entered the ABS pump box behind the drivers seat....one touch and the fluid started running....then another pipe....then another place...they were rotten through in all the little hard to see places

so first l replaced rotors, pads, flexible rubber with braided....l was basically trying to avoid ripping out the brake plumbing but eventually had to do it

cuts cursing and more cuts and a lot more cursing !, l think l bled more out of my hands spannering at the ABS pump than plunging them into a bucket of broken bottles. eventually got the rusted bolts off the ABS pan and dropped it down. then every unuion on the ABS was frozen on of course....that and every union on the whole brake system of course

eventually l got the main drivers side pipe bunch out after grinding off the plastic clips that hold the 6 pipes in place under the rocker

then there were the brake pipe cross overs....grrrrrrrrr

obviously when the car was made the crossover and corner brake piping was put on the frame with the body off. then the body goes on making a sandwich of the whole affair which is never intended to come out ....how the hell was l going to thread stainless preformed pipes around the tiny chassis spaces and to all the corners

so dumped the stainless idea and went with Cupronickel 'kunifer' brake pipe...thank god for that stuff....if its good enough for aston martin its good enough for me and was a whole lot simpler to bend, flare, and route to all the corners and across the car. Even if it wasnt identically bent to the pieces l took off it was functional and worked

so the end result was a lot easier than lt first looked but still a bitch ...l wouldnt want do it again unless someone paid me for it

however end result was that by poking about and doing the job was that l probably saved my life from some certain disaster when the rotten brake piping would have given out at a life altering moment

A whole brake line job is not for those who want a little weekend project...though lots of beer will help calm frayed hands and nerves

[Scrrem]

Yeah, that's the job I think I fear the most...trying to duplicate all those bends is damn near impossible. They without a doubt bent all the lines, installed them, then built the rest of the car around them. Mine are starting to look a little ratty but seem to be sound for the moment.
Rich

[xxxscimitarxxx]

The hardest part is stripping the old stuff out. The fear bit is thinking you have to replicate all the bends exactly. Just the main runs down the rocker from ABS pump to front are doable and then only approximately...at the end of the day it doesnt matter where they go unles you are some kind of concours purist and without doubt dont go stainless. Its a PITA to work with and cupronikel/kunifer works just as well. With cupro you can virtually bend everything with finger and thumb except for some tight radii. Plus the cupronikel flares easy using a cheap flaring kit. At the end of the day if the brake pipes end up running somewhere thats just convenient and clamped down with a cable tie...dont worry about it....l got rid of a few pointless bends that way

[Blue Flame Restorations]

Corvette Central offers pre-bent lines for most C4 years. I plan to order the closest year and use what I can and bend up what I'm forced to.

Glad to hear you got it done!!

[gbrtng]

The hardest part is stripping the old stuff out. The fear bit is thinking you have to replicate all the bends exactly. Just the main runs down the rocker from ABS pump to front are doable and then only approximately...at the end of the day it doesnt matter where they go unles you are some kind of concours purist and without doubt dont go stainless. Its a PITA to work with and cupronikel/kunifer works just as well. With cupro you can virtually bend everything with finger and thumb except for some tight radii. Plus the cupronikel flares easy using a cheap flaring kit. At the end of the day if the brake pipes end up running somewhere thats just convenient and clamped down with a cable tie...dont worry about it....l got rid of a few pointless bends that way

Was the corrosion from the outside or inside?
Did this vehicle have regular fluid flushes?

[tomtom72]

Oh man what a job! My hat's off to you on that one. :thumbsup:

Now I have another thing to check this winter. I rarely even look at the ABS pump. I'm afraid I'll give it some bad ideas if I start looking.

Hey, wait a minute. If our lines are s/s, how the heck did they rust thru in the first place? They have to be some cheap alloy or pure steel? Real s/s doesn't rust if it is at least 18/8 or better.

How did you bleed the ABS pump? Did you have a TECH1 or 1A?

:cheers:
Tom

[xxxscimitarxxx]

In order of questions....

I think the 5 prebents from ABS to front will be ok to install except as you go up to the front passenger side brake crossover pipe as it crosses the engine bay area, and driver side a bit easier. Two front and rear brake main supply pipes from rez to ABS connect to braided pipe coming from the reservoir (at least on my car) and low down near footwell so not so bad, and one 1/4" has a jubilee connect to rez rubber return (again at least on my car it is) also low down. Then each rear wheel seems to have especially complicated pipe bends which if supplied as bent l cannot see how you can thread it through the frame route without removing a lot of parts. Then theres the rear cross over which goes between batwing support and body, runs along rear chassis frame rail connector (two clips hold pipe) also a PITA to route if prebent....Im sure its possible to gently bend the stainles for a while but it will work harden at some point if manipulated too much

I think if l was in the US l would have ordered the stainless prebents as well and used what l could but as car is in UK the cost of shipping is stupid

As for how corrosion...definately outside .....car came from florida so that could have had something to do with it....that and coming to UK didnt help it with our weather and use of road salts in winter (mine is no trailer queen and gets driven as often as possible) the corrosion l found worst was as all 7 pipes go through an innocent rubber strip as it enters the ABS box. A lot of crap can get kicked up there and it will hold water

As for stainless on our cars.....they didnt come from factory with stainless l dont think, just hardened steel

As for bleeding......no luxury of Tech 1/1A lm afraid....just power bled all four corners and then the ABS bleed. It seems to have done the job and pedal is firm

However, did all this when l was last back in UK and havent hooked up the ABS elec bits and havent driven it yet. Brakes are now firm and seem to work fine with car on four axle stands But lm sure its going to throw up faults and codes....cross that bridge when l come to it

And a question from me

One strange thing l noticed while working on it.....l was able to start the car with all ABS disconnected but it wouldnt rev and would trigger a very low rev limiter if l tried......is this some kind of safety mode that ensure you dont have power if you have no ABS hooked up

[gbrtng]

And a question from me

One strange thing l noticed while working on it.....l was able to start the car with all ABS disconnected but it wouldnt rev and would trigger a very low rev limiter if l tried......is this some kind of safety mode that ensure you dont have power if you have no ABS hooked up
I have routinely disconnected the red power feed to the ABS unit and saw no indication other than a check ABS light in the DIC. Not sure what you mean by all ABS disconnected.

[xxxscimitarxxx]

ahhh....might have got that a genralized.....to get the ABS free to work on i disconnected all the wiring loom connections in the ABS box.....not sure that l was unplugging but l unplgged everything....and when started in that condition it wouldnt rev

added a pic of my tube plumbing

[TCurtner]

In order of questions....

I think the 5 prebents from ABS to front will be ok to install except as you go up to the front passenger side brake crossover pipe as it crosses the engine bay area, and driver side a bit easier. Two front and rear brake main supply pipes from rez to ABS connect to braided pipe coming from the reservoir (at least on my car) and low down near footwell so not so bad, and one 1/4" has a jubilee connect to rez rubber return (again at least on my car it is) also low down. Then each rear wheel seems to have especially complicated pipe bends which if supplied as bent l cannot see how you can thread it through the frame route without removing a lot of parts. Then theres the rear cross over which goes between batwing support and body, runs along rear chassis frame rail connector (two clips hold pipe) also a PITA to route if prebent....Im sure its possible to gently bend the stainles for a while but it will work harden at some point if manipulated too much

I think if l was in the US l would have ordered the stainless prebents as well and used what l could but as car is in UK the cost of shipping is stupid

As for how corrosion...definately outside .....car came from florida so that could have had something to do with it....that and coming to UK didnt help it with our weather and use of road salts in winter (mine is no trailer queen and gets driven as often as possible) the corrosion l found worst was as all 7 pipes go through an innocent rubber strip as it enters the ABS box. A lot of crap can get kicked up there and it will hold water

As for stainless on our cars.....they didnt come from factory with stainless l dont think, just hardened steel

As for bleeding......no luxury of Tech 1/1A lm afraid....just power bled all four corners and then the ABS bleed. It seems to have done the job and pedal is firm

However, did all this when l was last back in UK and havent hooked up the ABS elec bits and havent driven it yet. Brakes are now firm and seem to work fine with car on four axle stands But lm sure its going to throw up faults and codes....cross that bridge when l come to it

And a question from me

One strange thing l noticed while working on it.....l was able to start the car with all ABS disconnected but it wouldnt rev and would trigger a very low rev limiter if l tried......is this some kind of safety mode that ensure you dont have power if you have no ABS hooked up


How did you (does one) bleed the ABS unit? I see no bleeder valve - is it hidden? :handshak:

[tomtom72]

How did you (does one) bleed the ABS unit? I see no bleeder valve - is it hidden? :handshak:

I know that the 90 ABS pump has no bleeder.:) I also am fairly sure that some where along the production run the ABS pumps did grow a bleeder. I just don't know when that happened, 92 on up maybe?

The 90 FSM says to use a TECH1 or 1A with the ABS cartridge to activate the valves while a P-bleeder is attached to the master cylinder. I bleed the system, took it out for a test and using my foot activated the ABS several times. Back up on stands and re-bleed; back out & stomp the brakes & back again to bleed again. I did that 5 or 6 times and it seems to have worked. I suppose I could have bleed the pump at the lines inside the tub, but that would have been a major mess & working alone not too easily accomplished.

:cheers:
Tom

[xxxscimitarxxx]

The pic is of the ABS is on its side so top is facing you .....if you look closely you can see that just up and right of dead center of pic is a rusted bleed screw.....so basicallly if you were looking in the box from behind the car the bleed is on the right vertical side of the ABS.....mine was just rusted to hell

If l read right from what you are saying tom its sounding like the bleeding isnt goint to be a one time job.....sounds like several.....oh well l will take it out and stomp it and bleed it as neccessary untill happy....but l can get a vaccum bleeder on that bleed screw without too much problem now lve got the hang of working in that environment

[mike100]

seems like you could bleed the car as normal and maybe find a wet road to activate the unit, then rebleed again.

[xxxscimitarxxx]

HAHA.....Yes of course its the UK....wet roads are the norm