TheClairvoyant

I'm planning on replacing my original brake lines with new stainless steel lines.

I was all set to do it today. I couldn't find any suitable angle using a conventional wrench to turn the 17 mm nut on the on end where the brake line joins the hard line. The only way I could see would be to drop the exhaust which would free up room by getting the muffler & heat shield out of the way.

Would I be able to use a crowfoot wrench with a ratchet and long extension to avoid the headache of removing the exhaust or other items? I think it should work, but I wanted to ask on here first, since I've never actually used a crowfoot. If it should work, I'll go out an buy a set.

It looks like a pretty simple job if not for the tight working conditions...much like many 928 jobs.

Mrmerlin

a crow foot may round off the small line nut ..
best approach is to remove the wheel then spray the connection with PB blaster then heat with a heat gun then loosen the connection

borland

Tom,

No. Use only metric flare nut wrenches. They are designed to be used on tubing connector nuts. Open ended wrenches will distort the nut making it difficult to remove and replace.

There are better wrenches than these, but these might work..

http://www.harborfreight.com/hand-to...set-99993.html

There are some crowsfoot flare nut wrench sets, but they are not suitable for brake lines.

TheClairvoyant

Thanks for the responses.

jon928se

I might be wrong but doesn't the 17mm nut not actually turn - the only bit that moves relative to the chassis is the tube nut on the hard line ? Where the fitting passes through the bracket on the body the fitting is keyed to the hole in the chassis bracket.

GlenL

Be very careful with this. On an old car, and all 928s are old, the flare nut will often be corroded to the line. The fitting comes apart but the line gets twisted and, worst case, it gets twisted off. 2-3-4 turns and it's toast.

The safe approach is to remove the line from the caliper first. Then loosen the fitting. Counter hold both sides and only apply force by squeezing the two wrenches together. Once the fitting a loose then turn the brake hose around to unscrew it.

Don't forget the clip that holds the bake hose to the bracket. Pull that out with a pliers.

Once the hose is off you'll be able to see if the flare nut on the hard line is turning. take the time to get it turning easily. When it does, you'll be able to thread the new lines on and be sure the fitting isn't being cross threaded. If the nut needs a tool to be turned then you can't tell if it's going on straight.

If the nut is tight on the line work it free carefully. I use the line clamp part of a flaring tool to clamp the line tightly and right behind the nut. Work the nut back-forth until it is free. Apply penetrating oil. Use some heat if needed.

And enjoy!

TheClairvoyant

I thought it was the 17mm nut that turns and the small nut on the hard line was just to counterhold.

Is it actually the smaller nut on the hard line that turns? It would would be good to know so I don't try turning something that shouldn't turn and break it.

GlenL

Small nut is the "flare" nut and is supposed to turn.

In assembly, the line goes to the caliper first, then is attached to the hardline by threading in the flare nut. The hard line is "flared" at the end to make the sealing surface.

Mrmerlin

after you get the lines off use some anti seize on the connections so the flare nut has anti seize on its ID so it will slide on the line

TheClairvoyant

Thanks again for the responses. I'm going to be very careful with this. Seems like it could be very easy to wreck the hard line.

brianrheffron

Just a random thought about tools.
Since you always need two flare nut wrenches of the same size
to counterhold and then release flare nuts wouldn't it be more
logical to sell them in matching pairs. To get a pair of 17mms
I had to buy 10 wrenches (two sets of 5) leaving me with a bunch
of flare wrenches from 6mm to 22mm that will probably never use.
Same goes for ring spanners, open ended spanners and even ratchets
and sockets. You so often need two of the same size.

Mrmerlin

the key with the lines coming apart is to use a heat gun and the PB blaster HF has a good gun for about 29.00 it will work for this.
use 2 line wrenches the 17mm is the one thats not gonna move and the 10 or11 flare nut is what you have to turn

WallyP

I don't ever remember needing two flare wrenches the same size. The usual reason for flare wrenches is to avoid distorting the flare nut on a line. There usually aren't two flare nuts - instead there is usually a larger fitting (where you can use an open-end wrench) with a flare nut on the line.

The minimum wrench supply for serious work is a full open-end set, a full box-end set (ring spanners) and a full combination set. Then you get into long sets, stubby sets, offsets, crowfoot, etc., etc.

NEVER buy cheap flare wrenches...

brianrheffron

Wally, you are right about the differing sizes of the flare nuts.
I must have been thinking of the thin nuts that clamp the larger
fitting into the usually flimsy and rusted locating brackets.
More than once trying to free these I have twisted and
wrecked the brake hard line.

TheClairvoyant

I never expected so many replies to this thread. Thanks again. My original question was aimed merely at addressing the issue of limited working space. With all the answers, I've learned what a flare wrench is for and also pitfalls to watch out for when doing this job. That's what's great about Rennlist.

I'm off to buy a set of flare wrenches. In a few days I'll try to get around to replacing the lines (very carefully). Hopefully, it will be a success. Otherwise, I'll post a new thread titled "Help! I mangled my hard brake line."