UKKid35

One of my brake lines has a hole worn in it. One of the PS hose unions was rubbing and now there is a hole about 4" from the ABS pump under the LH coil. The line in question seems to run from the brake master to the ABS pump via the firewall (this is a RHD car). I guess a similar route on a LHD car would be the line from ABS pump to the RH front wheel.

The problem with removing and replacing is that there is loads of plumbing in the way, most of which will be awkward but not impossible. However the fuel cooler looks like it's going to be a real SOAB. I've not tried to remove the old brake line yet as the car has yet to be recovered, but any suggestions or advice would be very welcome indeed.

I'm assuming its not possbile to repair the punctured brake line, but if you know differently please let me know.

Thanks in advance

GlenL

Perhaps not "repaired" but the line can be cut with a compression fitting put in across the damaged section. You could try flairing the ends which would be a better seal.

I've done this and it works but tends to leak. Not really an appropriate solution. Still sometimes...

UKKid35

Is it possible to braise the line? What are they made of?

SharkSkin

I would not recommend trying to repair a brake line unless you are stranded far from home and only intend to drive home that way -- carefully. Unless you know of a shop that has the equipment to properly remanufacture the brake line, replace it with new. IMHO if there is only one system on the car where you would never want to do anything half-assed, it's the brake system.

YMMV

UKKid35

The only reason I was even thinking about it was because I can't see how to get a new one fitted. I'm really at a loss. Can a new line be threaded behind the fuel cooler? How much can you bend it when fitting it before you risk damaging it?

GlenL

Getting a new one in is the "fun" part. As they run along the walls they are put in first. Bending it will ruin the fit.

Sometimes I know I shouldn't offer such poor advice as splicing a brake line. Frankly a terrible idea from a safety perspective. But...If the joint is well done, and you watch the brake fluid level, it should hold you until you get the line and have a chance to put it in.

Never heard of it being brazed. Kinda doubt a commercial shop would do such a thing. (Anyone?)

SharkSkin

It sounds like a real PITA, but I think it would be worth taking the time to do it right. I thought it would be near impossible to get my AC line out to get it remanufactured(pic below) but I just worked through it step by step and made it happen. Above all, be patient and move whatever you have to. Not sure where the idea of brazing came in... I was thinking of a steel line with a rubber part swaged in somewhere.... I guess I'm just not visualizing the part in question. When my car was built the ABS pump was still on the drawing board.

Garth S

Paul,
I just went through repairing a fractured brake line on my Toyota T100 4x4. It was a section entering a splitter block and rising vertically into a three coil 2.5" diameter ' shock absorber' , and on to the firewall. We cut the line at the firewall and removed the fitting at the splitter. Using ~ 2 ft. of standard mild steel brake line, a new coil was made by winding around a piece of pipe. Fittings were applied - and a DOUBLE FLARE was made to the three open ends.
This long story is to illustrate that,
a) it is repairable by fitting in a section
b) brake line material can easily be shaped
c) a double flare tool is the way to go! ( the pipe is turned inward on itself by the first die - and then formed into the correct flare.

This gives a safe seal that meets local code. Compression fittings are not used in this service, and single flares are not as strong - and not recommended.

UKKid35

One possibility I'm considering is using Unions with compression fittings and and Bundy tubing. Is this out of the question? Finding a double flare tool does not look to be too easy, and using correctly it is probably even harder.

http://www.indanc.com/t06.htm#bundy_tube
http://www.indanc.com/compression_fi...ss_steel_union

Garth S

Take a quick read http://volksweb.relitech.com/brakeln.htm .
I just checked a 928 MC fitting, and Porsche (like VW) use a 'bubble' flare at factory connections vs the 'double' flare used by many others ( my error in noting the 'double' for the 928 ) Any automotive store here sells brake lines in various lengths with none,one or both flares applied. One can then cut & paste to fit, generally starting at the nearest fitting so as to use only one union in the line: no idea what Bundy tube is, or if it can readily be formed like the correct steel brake line.

UKKid35

Thanks Garth, it was Tom's site that encouraged me to look at the possibility of compression fittings, but other sites mainly aimed at racing applications have been very dismissive, indeed many encouraged the replacement of anything in a brake system that wasn't an AN fitting (mainly because it was anticipated that they would be regularly disconnected and then reconnected). Brake line pressures I've seen quoted are 1000psi plus, not sure whether compression fittings are good for that.

UKKid35

I have had a new line made up by a parts store for about $30, the bubble flares didn't look brilliant but I'm no expert. The Porsche price on PET (which must be out of date anyway) was £80 - about $150 but even if it was preformed perfectly it would still be neccesary to bend it to fit, so can't really see the advantge.

I've now fitted the line, looks ok, but I've yet to refill the system and bleed, so I'm keeping my fingers crossed that it's sealed properly. I even bought a flare nut spanner to ensure I torqued it properly.

SharkSkin

Great Paul, keep us updated!

UKKid35

I used a lot of brake fluid before finding the lines with all the air, but now that's done everything is working fine. I do recommend checking to see if anything is rubbing on your lines because it really is annoying when they fail. I do mean annoying rather than dangerous, because there certainly was plenty of warning when they failed.