Brakes Brake line flaring for Proportioning valve question?

derek1993

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Sep 13, 2020
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So the lines were going into the union where the Prop valve will go were seized, ended up having to cut them to get it out. Prop valve is 3/8-24, specific brake fitting that is needed when going into that prop valve? line size is 3/16?
put new ends on (have flared lines in the past, but been a minute) or would it be better to get new hard lines up front (albeit more expensive) from classic tube?
they seem to be seized up going into the distribution block as well (underside)
Trick to getting those things to break loose? i don't want to torque on them that hard and tweak the line.


Thanks.
 
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Mustang5L5

Put lubricant all over the balls
Mod Dude
Feb 18, 2001
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Brake line size is 3/16". At some point in the SN95 run, this changed to 6mm tubing.

If you can properly flare the lines, you can just go that route. If your build it one that focuses on looks, the SS tubing from classic tube is nice (i went that route) and does stand out nicely in the engine bay, which lookls great if the bay is detained and attractive. Some guys just want function, so really the decision is up to you.

PB blaster and a good brake line wrench will get them out. Don't use a regular wrench. Despite this, I've usually rounded them off, which means vice grips or channel locks get called out next.
 
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7991LXnSHO

wanna catch the space herp
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Sep 1, 2010
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A quality set of line wrenches is a good use of tool money while doing brake or fuel line work. Cheap ones are worse than a loose crescent wrench as they will round off six corners at a time instead of two.
 

Rdub6

So while I wait to figure out my rear end issues
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A quality set of line wrenches is a good use of tool money while doing brake or fuel line work. Cheap ones are worse than a loose crescent wrench as they will round off six corners at a time instead of two.
Add Duralast (from Autozone) flare wrenches to the “not so good”. Work fine on lines that are in good shape, but did exactly as you describe on ones that were a little rusted!
 

derek1993

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Thanks all, i have SAE and Metric Craftsman line wrenches, have worked in most cases including stubborn fittings.. haven't come across ones being as stubborn as these to be honest.. probably going after function for now.. when engine work comes into play (i.e. it comes out of the bay) i might update..
 

7991LXnSHO

wanna catch the space herp
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Sep 1, 2010
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Thanks all, i have SAE and Metric Craftsman line wrenches, have worked in most cases including stubborn fittings.. haven't come across ones being as stubborn as these to be honest.. probably going after function for now.. when engine work comes into play (i.e. it comes out of the bay) i might update..
The Craftsman line wrenches I got 3? years ago are like Rocket Science tools compared to the pre-HFT tool truck ones I was given as a gift. I should have bought the K-T set when I first started at NAPA.
Do you also have a tubing bender that has a grooved spool to keep kinks from happening when you make close turns?
 

derek1993

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Sep 13, 2020
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The Craftsman line wrenches I got 3? years ago are like Rocket Science tools compared to the pre-HFT tool truck ones I was given as a gift. I should have bought the K-T set when I first started at NAPA.
Do you also have a tubing bender that has a grooved spool to keep kinks from happening when you make close turns?
i don't, but not bending lines currently so don't have a need for a tubing bender.. the two areas where i need to flare i should just be able to cut and flare the straight lines that are intact.
 
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derek1993

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Sep 13, 2020
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received a flaring tool (capri) last night, bought a steel line @ 3/16" to practice with, have had good results so far. little more practice and i'll take the plunge.
at the area where the brake line union exists (where the prop valve will go).. should those be bubble flares or double flares? anyone know the fitting type that is used there? looks like it is one without a shoulder, but wanting to ensure i have the right ones.. otherwise will take what i have and match up based on size and known thread pitch, etc.
 

derek1993

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Sep 13, 2020
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Double flare was the type, impressed by that little flare tool. With proper prep (file and debur) the ends came out well (at least I thought). Will see how well I did when fliud goes through. Fighting with the distribution block at the moment. One free, cut and remaking the other. Getting my money's worth on the flare tool.
Stopped for the night, different fitting size on the back of the block.

Tool - Amazon productView: https://www.amazon.com/dp/B0859QMSNX?ref=ppx_pop_mob_ap_share


Amazon productView: https://www.amazon.com/dp/B000LDGNCU?ref=ppx_pop_mob_ap_share
 

HemiRick

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in my many years of experience, if the fitting are rusted, a flare nut nut wrench won't get them and you just need to move on to the small vice grips, they never fail.
 
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derek1993

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Sep 13, 2020
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so far so good, brakes bled today and checked all fittings. everything seems tight and dry at this point. but man, i must say that was some nasty brake fluid coming out of those lines..
 
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