Open Road

Hi Guys,

I want to change the soft lines for the SS braided ones but almost everything is seized at the hard line "T".
I want to change the hard lines too, but both the left and main one (from the front) are seized at the "T". The right one there is ok.
The oil you see is from the line at the top of the "T" (right side).
If I can get the left one out, that would be perfect. But is rounded a bit... :(
The last thing I want is to change the main line from the front...
Any trick to remove those line at the "T"?
Thanks in advance.

Induction heater.

https://boltbusterinc.com/

Get a proper 11mm flare wrench. Get the fitting smokin’. Brake fluid (no matter how much you drained) will shoot out the other end of the line, so consider that.

With the fitting smoking hot, use the flare wrench to “work” the fitting back and forth.

It may take 30+ minutes of heat, lather, rinse, repeat to get it free.

Counter hold the t-fitting.

You don’t want to mess up the supply line from the ABS pump (unless you have the motor out…)

Oh: *ventilate* you do not want to huff the fumes.

Thanks Dave.
I surely don't want to mess with the line from the ABS...
I'll take a good look at all your suggestions and get back with other questions if I have any.
Thanks again.

Bertrand Daoust wrote: ↑Thu Apr 18, 2024 7:45 pm Thanks Dave.
I surely don't want to mess with the line from the ABS...
I'll take a good look at all your suggestions and get back with other questions if I have any.
Thanks again.

There are, apparently, “Chineseium” induction heaters available from Harbor Freight if you don’t want The Real Deal.

To make sure, I need to open a bleeder nipple (or cut the line) before I heat anything, right?

I'm trying to find an induction heater near by from friends. I might end up buying a cheap one on Amazone or any where else. Any suggestion (link)?
Thanks again!

oh that looks like an ugly job Bertrand! Good luck with it.

Yes, not the easiest job I have done.
Should get through this one like others I have done in the past. At least, I hope! :)
Thanks Ed.

Bertrand Daoust wrote: ↑Fri Apr 19, 2024 9:49 am To make sure, I need to open a bleeder nipple (or cut the line) before I heat anything, right?

I figured you had your caliper and flexible line off already.

Having the caliper and line off is a prerequisite for using the induction heater on the t-junction fittings.

You can “unwind” the caliper from the flex line. If the flex-to-hardline junction is seized, you start there with the heater.

Whatever is “open” needs a catch bottle.

Bertrand Daoust wrote: ↑Fri Apr 19, 2024 9:49 am I'm trying to find an induction heater near by from friends. I might end up buying a cheap one on Amazone or any where else. Any suggestion (link)?

Sorry B. I posted my suggestion. I’ve no experience with the cheap knockoffs.

In other situations folks might suggest a propane torch. In that location I think that’s a recipe for disaster for melty bits.

You can try various ways to heat the fitting: high current soldering iron, contact heat transfer to the t-junction from something made red hot safely away from the melty bits, etc. Use your imagination.

Those will only work with a lot of luck. Induction heater acts directly on the steel of the fitting without as much direct effect on the hardline. The junction should be brass; it won’t heat as much. You need to “shock” the rust/corrosion on the threads and that between the fitting and the section of line about which the fitting must rotate. You need a lot of differential expansion, but in both vectors (expand away from line, contract in t-junction) of the fitting. Thus, why many cycles required.

And a reminder: use a proper flare/line wrench on the fitting when you are “working” it. Not an open-end wrench.

(I suppose you could slip, over the length of the hard line, a closed-end on it.)

Bought the flare/line wrench this morning.
Don't want to work there with open flame for sure. Thanks for reminder.
I can remove the soft line from the caliper without any problem.
Or simply cut it I guess.
I will go on with my search for an induction heater.
Thanks Dave (and all) for your help.
Appreciated.

worf wrote: ↑Thu Apr 18, 2024 7:38 pm Induction heater.

https://boltbusterinc.com/

Just watched a video on that tool...that's bad ass.. thanks for sharing.

checkmate1996 wrote: ↑Fri Apr 19, 2024 12:10 pm Just watched a video on that tool...that's bad ass.. thanks for sharing.

No fastener can withstand it :)

I did a 100% suspension/bushings/arms/brakes/knuckles/hub replacement on a ‘79 two years ago. Most of the fasteners hadn’t been touched since ‘79.

That tool got a workout and the job would have been almost impossible without it.

worf wrote: ↑Thu Apr 18, 2024 7:38 pm Induction heater.

https://boltbusterinc.com/

Get a proper 11mm flare wrench. Get the fitting smokin’. Brake fluid (no matter how much you drained) will shoot out the other end of the line, so consider that.

With the fitting smoking hot, use the flare wrench to “work” the fitting back and forth.

It may take 30+ minutes of heat, lather, rinse, repeat to get it free.

Counter hold the t-fitting.

You don’t want to mess up the supply line from the ABS pump (unless you have the motor out…)

Fwiw have had same issue. Oil soak plus heating with a soldering iron has done the trick for me. Yes to flare wrench! Tap around it. Then work back and forth for sure, and take your time.

Thanks for the tips Franke.
I'm waiting for parts right now.
I want to have everything in hand before doing anything else.
I have flare wrenches and an (cheap) induction tool in hand.
Thanks again.

My auto-shop teacher would slap the back of your head if he saw you touch a brake line with anything but a flare-nut wrench!

Hey Bertrand, are you re-using the rusted nuts you're trying to remove?
Are they going to hold the brake pressure or leak or are you installing new ones (this is my interest)

I see this repair in my future that's why I am so interested in this task.
Good luck

hessank wrote: ↑Sun Apr 28, 2024 9:06 am Hey Bertrand, are you re-using the rusted nuts you're trying to remove?
Are they going to hold the brake pressure or leak or are you installing new ones (this is my interest)

I see this repair in my future that's why I am so interested in this task.
Good luck

Once you get the hardline removed, as long as the hex-part of the fitting is in good shape you can ‘clean it up’, refinish it, and continue to use it.

If the fittings are too damaged for reuse then you have two practical choices:
- buy new lines from Porsche
- make your own lines from Cunifer and metric fittings with a flaring tool.

Replacing the fittings on the OE hardline is a practical impossibility unless you have access to a *big* hydraulic flaring tool.

Hi Fred,

I'm changing the two rear brake lines for new ones (from Porsche). Top and bottom ones at the "T".
My plan is to keep the "T" in place as I don't want to mess with the front line from the ABS. Left line on the "T".
I'm also changing all four soft lines.

Thanks gentlemen

A little update...
Both side rear hard lines are removed.
Induction heater, flare wrench, vise grip, cutter did the trick.
Now I will need to pass the new right line over the transmission... Hum...
There is two plastic holders. One is quite easy to reach but I had to cut the line to slide it out of the second one. Right over the transmission. The new line will not go through this one for sure... No, I'm not dropping the transmission to put it back there... :)
Thanks for your help.
Should have the parts this week. Hope to have everything done (for that job) by the end of this week.
More to follow...

Bertrand Daoust wrote: ↑Sun May 05, 2024 4:57 pm Now I will need to pass the new right line over the transmission... Hum...
There is two plastic holders. One is quite easy to reach but I had to cut the line to slide it out of the second one. Right over the transmission. The new line will not go through this one for sure... No, I'm not dropping the transmission to put it back there... :)

I have fitted new ones without dropping anything. I don’t recall any super special trick. Maybe I needed to loosen an axle shaft or something.

Stare at it a while and it’ll come to you.

Those OE lines are super tough. Don’t be afraid of bending it just a bit if you have to.

All the back is done.
New hard lines and SS soft line are installed.
Everything went well.
No problem at all installing the right hard line over the transmission.
The only thing is that it's clipped only on one of the two plastic support.
No way to get to the one over the transmission...
Next is the front.
Waiting for information on the banjo bolts. The ones supplied in the kit are too long.
While working on rear brake line, I removed the muffler from the cat and painted the 3 heat shields.
Everything is back in place.

Good work B.

So… what are the zip ties on the transaxle crossmember doing?

Thanks Dave.
I knew you would notice... :)
I don't remember exactly, but I think they're there to help to hold the parking brake cable on the other side of the cross member that was not tight enough for me. I did that job in 2010 if I remember well.

Hey Bertrand. I did a test on a set of the banjo bolts on an S4 caliper today and found the issue. It's not the length of the threaded portion but the depth of the bolt head on the new bolts. It's off by a bit less than a mm but that is preventing the crush on the washers. Roger is going to talk to the manufacturer about this. If you double up on the crush rings on the head side they will fit (not ideal) or re-use your old bolt and it will be fine.

Nice work Bertrand!

Thanks Ed.

The car is back on the road! :)

As usual Bertand, excellent work! You are giving me hope.

What is the red material at the joint? Is this some type of sealant?

There's hope for sure brother!
Just take your time and it will be fine.
Like many jobs on a 928, at least for me, you know when you start, but never know when you'll be done. :)
I would say that the red material is red Loctite. Or something similar.
That's why it's quite tight and needs heat to release the grip.

The red is a factory paint mark for torque.

Those union nuts have torque values.

When you heat these brake line fittings, hot brake fluid is going to squirt out any opening in the system.

Even if you think you’ve drained the system.

You do not want your face in that stream of hot brake fluid.

You also don’t want it shooting out across the shop onto a painted or otherwise damageable surface unnoticed.

Figure out from where the hot fluid will be squirted and take appropriate measures.

worf wrote: ↑Tue Mar 11, 2025 2:54 pm The red is a factory paint mark for torque.

Those union nuts have torque values.

It's German.

EVERYTHING has a torque value.

This is kicking my ass! I have the Induction Heater from Otto. I first tried the connection from the hard line to the soft line where I rounded the nut. I wasn't making any headway. Then I figured since I am replacing the small hard line anyways, I should just disconnect at the T. Been working on it for two hours. NO SUCCESS.

Heating it then PB blasting ( also ATF/Acetone) try and turn. Over and over. Maybe this is "feel" thing that I can't grasp. Should I be trying to turn quickly or a steady pressure turning?

I had to walk away. That's why I'm posting this.

How hot are you getting it?

WyattsRide wrote: ↑Sat Mar 15, 2025 2:22 pm This is kicking my ass! I have the Induction Heater from Otto. I first tried …

Take a picture of the induction heater in position such that if you were to activate it, it would be doing what you think it should be doing.

IOW, based upon the picture you just sent you would not be able to use my Bolt Buster, yet. Maybe Otto’s is different?

I need to see the heating element and the line junction in position.

WyattsRide wrote: ↑Sat Mar 15, 2025 2:22 pm This is kicking my ass! I have the Induction Heater from Otto. I first tried the connection from the hard line to the soft line where I rounded the nut. I wasn't making any headway. Then I figured since I am replacing the small hard line anyways, I should just disconnect at the T. Been working on it for two hours. NO SUCCESS.

Heating it then PB blasting ( also ATF/Acetone) try and turn. Over and over. Maybe this is "feel" thing that I can't grasp. Should I be trying to turn quickly or a steady pressure turning?

I had to walk away. That's why I'm posting this.

Rick - are you replacing that line? If so, cut it off at both ends, then fit a dep socket over the nut and take it off that way. Also, try vice grips on the rounded one.

linderpat wrote: ↑Sun Mar 16, 2025 12:05 am Rick - are you replacing that line? If so, cut it off at both ends, then fit a dep socket over the nut and take it off that way. Also, try vice grips on the rounded one.

That’s how he got into this mess in the first place.

Rick, send me a picture of the business end of the induction heater as described above.

worf wrote: ↑Sat Mar 15, 2025 3:48 pm

WyattsRide wrote: ↑Sat Mar 15, 2025 2:22 pm This is kicking my ass! I have the Induction Heater from Otto. I first tried …

Take a picture of the induction heater in position such that if you were to activate it, it would be doing what you think it should be doing.

IOW, based upon the picture you just sent you would not be able to use my Bolt Buster, yet. Maybe Otto’s is different?

I need to see the heating element and the line junction in position.

I'll do that today. I'm pretty sure it's getting hot. The PB blaster starts smoking and sizzling.

linderpat wrote: ↑Sun Mar 16, 2025 12:05 am Rick - are you replacing that line? If so, cut it off at both ends, then fit a dep socket over the nut and take it off that way. Also, try vice grips on the rounded one.

The rounded nut connection to the soft line is not even a concern anymore, since below. The only reason I tried there first with the Induction Heater was for practice. But, I then figured I was wasting time on it.

Yes, I planned on replacing that small hard line because I've already rounded that connection nut to the soft line. Your suggestion was already my next action. I figured I could cut the line close to the nut at the T, remove the rest of the line at the bracket and use a socket on the nut at the T. This would also get me in a better position for leverage. There is very little room for the line wrench to turn.

The only reason I didn't try that yet, was my concern for all the brake fluid that would come out. Right now I have the cut, soft line clamped, so no BF is leaking out all over the place. If it wasn't clamped, will ALL the BF leak out of the whole system?

worf wrote: ↑Sun Mar 16, 2025 7:03 am

linderpat wrote: ↑Sun Mar 16, 2025 12:05 am Rick - are you replacing that line? If so, cut it off at both ends, then fit a dep socket over the nut and take it off that way. Also, try vice grips on the rounded one.

That’s how he got into this mess in the first place.

Rick, send me a picture of the business end of the induction heater as described above.

Dave, wouldn't a socket have better/more contact points for gripping the nut, than even a line wrench?

Rick, was the PB you put smoking when you were heating the connection?
It should come red or close and smoking like Dave said.
If there was no smoke, it was probably not warm enough.

N_Jay wrote: ↑Sat Mar 15, 2025 3:41 pm How hot are you getting it?

I thought hot enough. Maybe not. IDK

Bertrand Daoust wrote: ↑Sun Mar 16, 2025 8:39 am Rick, was the PB you put smoking when you were heating the connection?
It should come red or close and smoking like Dave said.
If there was no smoke, it was probably not warm enough.

Yes it was smoking.

Here's pics of the Induction Heater and the coil in place around the nut.



Here's how I try to get the coil around the nut.

WyattsRide wrote: ↑Sun Mar 16, 2025 10:14 am Here's how I try to get the coil around the nut.

Ok. That's what I figured based upon the original picture... and it's not gonna work very well.

The loops of the induction heater need to loop around the objective. Not loop around the air in the vicinity. That's why it isn't getting hot. And, in your current situation you have no way to "thread" the induction heater loops over the union nut.


Here's what you need to do:

1) Cut the hard line.

Yes. All the brake fluid is going to drain out of the system. That ship has sailed. And even more will squirt out once you heat up the lines. (You were going to have to do a pressure bleed anyway. So, worrying about more fluid loss isn't "a thing.")

Once the hard line is in two pieces you can pull the retainer for the outboard union and withdraw the soft line and the part of the hard line to which it is attached.

2) Slip some hose, tubing, something over the open end of the hard line and direct the output to a bucket. (Have the bucket and hose ready to deploy before you cut the hard line.) You want enough hose to direct the fluid spray but no so much that it's hard to thread and unthread the heater's coil.

3) Rewind the loops of the induction heater so that they look like the picture below. (You don't need all three coils shown. Two will do.)

4) The nut is very unlikely to simply break free in one go. You will need to break it loose in stages.

This is the process:

- thread the induction heater's coil around the hose and the remainder of the line until the coils are around the union nut. The coils must never touch the fastener (or anything else) for any non-near-instantaneous amount of time.

- heat until it's smokey. Hot brake fluid will shoot out of the line into you bucket.

- withdraw the heater

- counter-hold the t-junction with smooth jaw pliers

- work the nut back and forth with the flare wrench. Use moderate pressure. More than "wrist" pressure. Less than "full arm" pressure. Make sure you aren't transferring more than little force on the t-junction. Put some "loosening" pressure on it. Then some "tightening" pressure. Obviously you want to use a lot of pressure but not nearly so much that you round off the nut. Repeat this back and forth for a few minutes until the joint's cooled off a bit.

- Spray the joint with your preferred "stuff" (You can do this after you heat too, but, it's nasty...)

- Put the tools down and do something else for 10 minutes or so.

- go back to the "thread the induction heater's coil" step.

Repeat this process until it comes loose.

*** It may take three or four repeats before you get a hint of movement. ***

You will get a feel for how hot to make the union. Hotter is better.

Pay attention that you aren't burning anything. The hard lines and junctions will get hot. The may transfer heat to other parts. Don't go crazy. You probably won't be able to make the union nut "red" hot.

5 to 10 seconds of the induction heater should result is some serious smoke. You might want a fan blowing on your face. That "smoke" will be toxic.

@linderpat

Yes, a socket will give you more purchase but, the union nut needs to be "worked" back and forth which is hard to do with a socket unless you have an offset t-handle adapter for it.

It's also important to observe the junction during the process.

And, hot brake fluid will be dripping on you since you can't use both a t-handle adapter and a hose.

After the fifth or sixth repeat, dripping hot brake fluid will probably be done.

Thanks Dave. I'm going back in.........

I cut the hard line and removed the remaining from the bracket. Then I did this test.

Rounded nut connection in the vice. Put the Induction Heater coil over the nut as it should be. Heated, PB Blaster X 2. Third time getting the nut RED Hot, a little twist and out it turned. So I know it can be done (in a nice controlled environment of a vice)







Been doing the real nut at the T, the same way several cycles now.......Still not budging.

I GOT YOU M-Fer!!!!



I used a closed ratcheting wrench and a pipe at the end for leverage. I was ecstatic when it broke free!!

I'm done for the day. Next weekend the Right side Hard Line/Soft Line connection.

WyattsRide wrote: ↑Sun Mar 16, 2025 5:03 pm I GOT YOU M-Fer!!!!

Excellent.

WyattsRide wrote: ↑Sun Mar 16, 2025 5:03 pm I'm done for the day. Next weekend the Right side Hard Line/Soft Line connection.

Given how easy the left side was, I’d use the induction heater straight away on the right side.

Turn the caliper off the soft line. Widen out the heater coils. Thread coils over soft line to the union.

Might not have to replace the right-side branch hard line.