Home  |  Forums  |  914 Info  |  Blogs
 
914World.com - The fastest growing online 914 community!
 
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG. This site is not affiliated with Porsche in any way.
Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners.
 

Welcome Guest ( Log In | Register )

 
Reply to this topicStart new topic
> Any Tips, Tricks, Old School Methods, etc. to loosen stubborn brake line fittings?
914rrr
post Aug 10 2026, 10:04 PM
Post #1


Advanced Member
****

Group: Members
Posts: 2,097
Joined: 1-July 03
From: McMinnville, TN
Member No.: 874
Region Association: South East States



Working on my brakes and installing new soft lines in the rear. Used PB Blaster to baptise both soft line fittings to hard lines that to go the proportioning valve. Re-applied each day for a few days.

Went to remove the drivers side soft line and the fitting rounded off before the hard line snapped of just above the fitting. Had a crummy made in India flare wrench laying around that spread right away and was quickly useless. Tried again with an 11 mm Proto combo wrench on the hard line barrel and a 17 mm Indian flare on the bottom soft line. Thought I was making progress until the line broke off just above the fitting (IMG:style_emoticons/default/headbang.gif)

Now, I have to replace the drivers side hard line that goes on TOP of the proportioning valve, and possibly the other twin line going to the passenger side. How do you remove THAT fitting on top without pulling the engine?

I could barely get an 11 mm stubby combo wrench on it, but have almost zero room to twist it. I'm in need of solutions, ideas, old timer trick, tips if anybody has any.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
bdstone914
post Aug 10 2026, 11:22 PM
Post #2


bdstone914
*****

Group: Members
Posts: 5,374
Joined: 8-November 03
From: Riverside CA
Member No.: 1,319



QUOTE(914rrr @ Aug 10 2026, 09:04 PM) *

Working on my brakes and installing new soft lines in the rear. Used PB Blaster to baptise both soft line fittings to hard lines that to go the proportioning valve. Re-applied each day for a few days.

Went to remove the drivers side soft line and the fitting rounded off before the hard line snapped of just above the fitting. Had a crummy made in India flare wrench laying around that spread right away and was quickly useless. Tried again with an 11 mm Proto combo wrench on the hard line barrel and a 17 mm Indian flare on the bottom soft line. Thought I was making progress until the line broke off just above the fitting (IMG:style_emoticons/default/headbang.gif)

Now, I have to replace the drivers side hard line that goes on TOP of the proportioning valve, and possibly the other twin line going to the passenger side. How do you remove THAT fitting on top without pulling the engine?

I could barely get an 11 mm stubby combo wrench on it, but have almost zero room to twist it. I'm in need of solutions, ideas, old timer trick, tips if anybody has any.


I use a pair of Knipex plyers. Thry have jaws shaped to fit the hex. They do not kick back from the pressurevof trying to open them. Everest makes a similar pair. I descovered them in Saab tool kits. They work on hev nuts from 10-27mm. I have removed rear shock nuts with them.


Attached thumbnail(s)
Attached Image
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
bdstone914
post Aug 10 2026, 11:31 PM
Post #3


bdstone914
*****

Group: Members
Posts: 5,374
Joined: 8-November 03
From: Riverside CA
Member No.: 1,319



Do you use a torch to heat the fitting. I rdid that recently. Used tust penetrent then heat. Gave it a good amount of heat then walked away. Heard a bang. The rubber hose was blown off the flex line. And the system was open on that end. Did not make sence but it happened.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Jack Standz
post Aug 10 2026, 11:41 PM
Post #4


Senior Member
***

Group: Members
Posts: 915
Joined: 15-November 19
From: Happy Place (& surrounding area)
Member No.: 23,644
Region Association: None



Somebody recommended these ratcheting flare wrenches, but haven't pulled the trigger yet to buy them, so can't offer any personal experience with them:

https://www.amazon.com/gp/product/B0CCZTQX43?psc=1&th=1

Amazon.com sells them as individual wrenches too, if you're not up to get the whole set.

Here's a set with flexible heads that might help with that stubborn one on top of the brake pressure regulator.

https://www.amazon.com/PRIDE-CRAFT-Flex-hea...164&sr=8-11
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
porschetub
post Aug 11 2026, 12:12 AM
Post #5


914 Guru
*****

Group: Members
Posts: 5,166
Joined: 25-July 15
From: New Zealand
Member No.: 18,995
Region Association: None



QUOTE(914rrr @ Aug 11 2026, 04:04 PM) *

Working on my brakes and installing new soft lines in the rear. Used PB Blaster to baptise both soft line fittings to hard lines that to go the proportioning valve. Re-applied each day for a few days.

Went to remove the drivers side soft line and the fitting rounded off before the hard line snapped of just above the fitting. Had a crummy made in India flare wrench laying around that spread right away and was quickly useless. Tried again with an 11 mm Proto combo wrench on the hard line barrel and a 17 mm Indian flare on the bottom soft line. Thought I was making progress until the line broke off just above the fitting (IMG:style_emoticons/default/headbang.gif)

Now, I have to replace the drivers side hard line that goes on TOP of the proportioning valve, and possibly the other twin line going to the passenger side. How do you remove THAT fitting on top without pulling the engine?

I could barely get an 11 mm stubby combo wrench on it, but have almost zero room to twist it. I'm in need of solutions, ideas, old timer trick, tips if anybody has any.

Bugger that's a whole world of trouble ,buy/loan a flaring tool and use VW jointers which are used on 80s and 90s Golfs ,they are normally used on the engine side of the firewall ,chop them out of a pick and pull wreak.
Use a bit of heat on the bad fitting and get yourself some decent brake line spanners ,good luck ,cheers.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
BillC
post Aug 11 2026, 08:16 AM
Post #6


Senior Member
***

Group: Members
Posts: 748
Joined: 24-April 15
From: Silver Spring, MD
Member No.: 18,667
Region Association: MidAtlantic Region



If you are replacing the line (hard or soft) anyway, just cut the line and use a box-end wrench or socket to loosen the fitting.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
brant
post Aug 11 2026, 08:29 AM
Post #7


914 Wizard
**********

Group: Members
Posts: 12,272
Joined: 30-December 02
From: Colorado
Member No.: 47
Region Association: Rocky Mountains



Try aero kroil
I find it much better than pb
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
emerygt350
post Aug 11 2026, 09:45 AM
Post #8


Advanced Member
****

Group: Members
Posts: 3,720
Joined: 20-July 21
From: Upstate, NY
Member No.: 25,740
Region Association: North East States



Watch any episode of vice grip garage....
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Chris H.
post Aug 11 2026, 10:59 AM
Post #9


Senior Member
****

Group: Members
Posts: 4,106
Joined: 2-January 03
From: Chicago 'burbs
Member No.: 73
Region Association: Upper MidWest



QUOTE(emerygt350 @ Aug 11 2026, 10:45 AM) *

Watch any episode of vice grip garage....

LOL exactly! He always says "heat, juice, juice, heat, heat, juice, heat...repeat..." using some sort of penetrant like kroil or PB Blaster

He also tries to tighten the nuts as well as loosen them and has a wrench on both sides to try to prevent snapping an ancient hard line.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
VaccaRabite
post Aug 11 2026, 11:13 AM
Post #10


En Garde!
**********

Group: Admin
Posts: 13,912
Joined: 15-December 03
From: Dallastown, PA
Member No.: 1,435
Region Association: MidAtlantic Region



I usually just accept that I'm going to break a 50 year old hard line when I try to remove it - no matter what I do. And have new lines waiting to go.

But, yeah. heat and juice. I prefer my hope brew (50%ATF, 50%acetone) but PB works.

Zach
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
914rrr
post Aug 11 2026, 11:27 AM
Post #11


Advanced Member
****

Group: Members
Posts: 2,097
Joined: 1-July 03
From: McMinnville, TN
Member No.: 874
Region Association: South East States



Thanks everyone! I was told by another member here that rubber brakes lines can exploded when heated sometimes. Never knew that before.

Speaking of heat, is it OK to apply heat to the proportioning valve?
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Cvrguy
post Aug 14 2026, 03:17 PM
Post #12


Newbie
*

Group: Members
Posts: 42
Joined: 18-September 25
From: Los Angeles
Member No.: 28,995
Region Association: None



I did what BillC did, cut the old rubber hose just above the fitting a use a socket. I shot mine with PB Blaster and let it sit overnight. Mine were original lines from 1973 and the came off easily this way.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
emerygt350
post Aug 14 2026, 04:25 PM
Post #13


Advanced Member
****

Group: Members
Posts: 3,720
Joined: 20-July 21
From: Upstate, NY
Member No.: 25,740
Region Association: North East States



That's the other vgg bit of advice. Sacrifice the rubber hose. You are replacing it anyway. You want to protect the steel line. Cut the rubber, use a socket, clamp the steel line. Heat, juice heat juice...
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
914rrr
post Aug 18 2026, 09:45 PM
Post #14


Advanced Member
****

Group: Members
Posts: 2,097
Joined: 1-July 03
From: McMinnville, TN
Member No.: 874
Region Association: South East States



Success!! I was able to remove the passenger side hard line flare nut from the soft line AND the top flare nut on the broken drivers side hard line without damaging either! (IMG:style_emoticons/default/dancinnanner.gif)

I bought one of the cheap flare nut crows foot wrench sets from Walmart and a 3/8" flexible ratcheting T-Bar from Harbor Freight.

These made removing and reinstalling the driver's side hard line's top flare nut on the proportioning valve possible. I honestly don't think I could have removed that top flare nut or reinstalled the new one without them!

I also used my trusty vintage 3" C-Jaw Vice Grips (favorite tool in my tool box!) to hold / brace the passenger side rubber hose fitting and the 11 mm flare nut crows foot on the hard line fitting with a 3/8 swivel head ratchet and a long 3/8 extension.

Attached Image

Attached Image

Attached Image

Attached Image

Attached Image
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
rgalla9146
post Aug 19 2026, 06:09 AM
Post #15


Advanced Member
****

Group: Members
Posts: 4,996
Joined: 23-November 05
From: Paramus NJ
Member No.: 5,176
Region Association: None




Ancient brake hoses swell inside.
When this happens that caliper remains pressurised. It's also impossible to bleed.
If you heat the fitting with the hose attached you risk explosion.
Cut the hose off at the fitting.
Hold the steel tube fitting however you can in its present position to prevent
twisting, Turn the old rubber hose end piece off the tube fitting.
If the steel tubing is still in excellent condition with just the end fitting stuck,
heat the fitting only. It will free up easily.
This method is especially useful on 914 rear hoses just below the engine
shelf.
Use a brake adjusting tool and/or a vicegrip to lever the clip off the chassis
mount.


User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Root_Werks
post Aug 21 2026, 10:39 AM
Post #16


Village Idiot
*****

Group: Members
Posts: 9,053
Joined: 25-May 04
From: About 15NM from Canada
Member No.: 2,105
Region Association: Pacific Northwest



QUOTE(Chris H. @ Aug 11 2026, 09:59 AM) *

QUOTE(emerygt350 @ Aug 11 2026, 10:45 AM) *

Watch any episode of vice grip garage....

LOL exactly! He always says "heat, juice, juice, heat, heat, juice, heat...repeat..." using some sort of penetrant like kroil or PB Blaster

He also tries to tighten the nuts as well as loosen them and has a wrench on both sides to try to prevent snapping an ancient hard line.


(IMG:style_emoticons/default/agree.gif)

Just went through this on some crusty fittings. It works.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post

Reply to this topicStart new topic
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:

 



- Lo-Fi Version Time is now: 9th September 2026 - 10:46 PM
...