Brake lines replacement

[mutley]

Hi All,

Now, I know there are many places that do replacement brake line flexi-hoses, but can any one advise what is best for replacing the hard lines? any particular material ( e.g. copper) or which diameter of pipe etc?

Cheers
Jim

[britlude]

brake lines are a standard size 3/16", just go for Kunifer pipe, it'a a copper/nickel alloy that's less prone to cracking (apparently) than straight copper....

that's if you don't want to go OEM of course


and get a decent flaring tool!

[Kaz-kzukNA1]

Jim, bit more info or photo of which section to be dealt with would help.

For example, entire section of Front Right corner between the fitting inside wheel arch and the one at the ABS or is it something that can be repaired by replacing small part of the hard line?


Kaz

[mutley]

This is the corroded part, but as I am doing quite a bit of work to the car, I thought it would be best to replace as much as I can.

Cheers,
Jim

[Kaz-kzukNA1]

That's the Rear Left corner and based on the state of the suspension spring and the bracket for the wheel speed sensor, you may also want considering replacing the brake hose together with the pipe/hard line.

OEM brake hose is long lasting reliable parts but there were enough reports of hose splitting at the metal fitting or the hose bracket where the edge of the crimped section ends.

For the Rear side hard line, both has a joint inside the eng bay.
For the Rear Right, I normally replace entire section while the eng is out of the bay.
For the Rear Left, probably manageable if removed surrounding parts.

If doing lots of DIY pipe job, as Jonathan mentioned, Kunifer is the one to go.
As it's already widely used, I 'think' there is no regulation against the use of copper or Kunifier in UK.
In Japan, the regulation allows the use of it but many are applying extra protection such as heat shrink tube, coating, etc against the stone/sand chip if installed in such environment.

If just a few pipes, check the price of OEM ones or take the removed pipes and get estimate who already has the tools and the materials.
Or, normally people just replace the section of the pipe affected as long as the rest of the pipe is healthy.

Kaz

[mutley]

That's the Rear Left corner and based on the state of the suspension spring and the bracket for the wheel speed sensor, you may also want considering replacing the brake hose together with the pipe/hard line.

OEM brake hose is long lasting reliable parts but there were enough reports of hose splitting at the metal fitting or the hose bracket where the edge of the crimped section ends.

For the Rear side hard line, both has a joint inside the eng bay.
For the Rear Right, I normally replace entire section while the eng is out of the bay.
For the Rear Left, probably manageable if removed surrounding parts.

If doing lots of DIY pipe job, as Jonathan mentioned, Kunifer is the one to go.
As it's already widely used, I 'think' there is no regulation against the use of copper or Kunifier in UK.
In Japan, the regulation allows the use of it but many are applying extra protection such as heat shrink tube, coating, etc against the stone/sand chip if installed in such environment.

If just a few pipes, check the price of OEM ones or take the removed pipes and get estimate who already has the tools and the materials.
Or, normally people just replace the section of the pipe affected as long as the rest of the pipe is healthy.

Kaz

Hi Kaz,

As always, you are the font of all knowledge on this. (yes you noted the condition of the springs...... they are going too). Due to the age of the car and spent most of it's life outside, i'm just trying to replace as many components as I can.

Cheers
Jim

[mutley]

brake lines are a standard size 3/16", just go for Kunifer pipe, it'a a copper/nickel alloy that's less prone to cracking (apparently) than straight copper....

that's if you don't want to go OEM of course


and get a decent flaring tool!

The garage that's doing the rest of the work will be doing this, so that'm more parts replaced!

Cheers
Jim

[Old guy]

A bit late to the party. You can find hard lines in 3 materials; steel (various grades with or without galvanizing), stainless steel and copper/nickel/ iron. In North America copper/nickel/iron is generically referred to as Cunifer (Cu Ni Fer). Kunifer might be the term in GB or a particular trade name. I believe Cunifer / Kunifer orginated in Europe years ago.

If you were doing it yourself (I have done it - not on the NSX) I would say Cunifer is the hands down winner. Not only is it corrosion resistant, it bends nicely and accepts fairly tight radius bends. Stainless steel looks nice; but, is the absolute worst to work with. Since you are having a shop do the line replacement for you, I expect that Cunifer will probably be their default material just because it is so much easier to work with (time is money!). From personal experience the biggest contributor to a successful job is the quality of the flares on the tube ends. Be aware that there is a difference between the flare angles on JIS and none JIS metric fittings (Kaz can probably elaborate). If you go to a brake specialist or Asian car specialist they are probably aware and have the proper flares. If you go to a European car specialist - might want to confirm that they know about all the flare variations.

Reusing the fittings is OK. However, if the flats on the nut have been rounded off in removal you might want to plan for new nuts (which have to go on before the tube is flared). That may or may not be a problem depending on the shop's inventory of the correct JIS fittings.