Need help wrapping up this disk brake conversion (brake line related)

[Artikgrau325is]

Hello everyone! I purchased a front disk brake conversion from Tomsclassics on Ebay, and so far everything has been a relatively painless install (we shall not talk about the days spent trying to separate ball joints).

I'm nearing the finish line, and I've got the booster/master/and prop valve mocked up to make sure everything fits. It was here that I hit a snag with my brake lines:



As many of you know, the stock lines (at least on a drum equipped 68 C10) came straight up underneath the prop valve. Now I need them to go to the front and rear.

Not to be a bugaboo, I commenced searching this very forum, as it usually answers the majority of my questions. Unfortunately I'm not getting very clear answers pertaining to my situation. Most of the disk brake conversions I've seen on here are from a 71-87 truck, not an aftermarket install. As for answers, folks seem to lean on the custom brake line setup.

After searching for a few hours I found some threads related to my issue, but they're quite old now and don't exactly have the precise answers I'm looking for. Perhaps there's some super easy adapter kit available now, I don't know.

http://67-72chevytrucks.com/vboard/s...d.php?t=221180



To be honest I want to finish this as painless as possible. I don't know how to bend custom tubing, I have no clue what size adapters/fittings I need, and I'm hoping that someone here could offer up a solution. Even something as simple as "all you need is front brake lines off a 71-72" would be awesome.

So far I've deduced that:

-I can plug the top fitting for the front wheels, and feed them both from the lower front, instead of running two separate lines for the front wheels.

-My stock brake line fittings right now are 9/16 to rear and 7/16 to front. That's the wrench size, not sure what size the fitting would be.

If anyone can help me out with this, it would be greatly, greatly appreciated. Thank you all for your time,

-Mike.

[davepl]

You'd have to measure the lines, not the nuts. Likely 1/4 and 3/16 OD.

Because you're not using a stock style prop valve, your only choice is to make your own lines or have someone make them for you. You don't have to do the whole truck, just from the prop valve to the front T and from the prop valve to the rear union (about where the heat riser is on the passenger side). About 3-4 feet each.

If your local auto parts store rents a hydraulic flaring tool like the Mastercool or its various re-brands, it makes flaring painless and simple. Can still be done with hand tools on the cheap though.

If you're at all worried, pay someone to do it. As I've said before, good brakes are cheap life insurance and you should save money elsewhere when in doubt.

[davepl]

Hey, if you're in the Seattle area, take it to Preston Automotive (just off the 202 in Redmond). They only do old vehicles, they have a cheap guy that will flatbed it for you, and I've seen their brake-line work many times. It'll look like stock, only nicer.

http://rpmdyno.com

As for Jim or Paul. Jim's the owner, and he'll make Paul do the lines :-)

[Artikgrau325is]

Originally Posted by davepl

You'd have to measure the lines, not the nuts. Likely 1/4 and 3/16 OD.

Because you're not using a stock style prop valve, your only choice is to make your own lines or have someone make them for you. You don't have to do the whole truck, just from the prop valve to the front T and from the prop valve to the rear union (about where the heat riser is on the passenger side). About 3-4 feet each.

If your local auto parts store rents a hydraulic flaring tool like the Mastercool or its various re-brands, it makes flaring painless and simple. Can still be done with hand tools on the cheap though.

If you're at all worried, pay someone to do it. As I've said before, good brakes are cheap life insurance and you should save money elsewhere when in doubt.

Ahhh, I didn't know that was how brake lines were measured, makes a lot more sense now (and shows that the kind auto part employees also don't know this either, heh.) I'm thinking I will get a bunch of line and practice on it, while it seems like a bear I'd rather spend $60 and gain a new skill than $200 for prebent lines and having to worry about things not lining up. My frame off build is getting everything new from the ground up so I suppose I would have run into this problem eventually.

At the very least, you have graciously pointed me in the right direction, I appreciate that very much.

Originally Posted by davepl

Hey, if you're in the Seattle area, take it to Preston Automotive (just off the 202 in Redmond). They only do old vehicles, they have a cheap guy that will flatbed it for you, and I've seen their brake-line work many times. It'll look like stock, only nicer.

http://rpmdyno.com

As for Jim or Paul. Jim's the owner, and he'll make Paul do the lines :-)

Hmmmm, you know I've been looking for a decent hotrod shop around here. I'd love to check them out and maybe learn a thing or three. Thank you for the reference bud!

[chevy72blu]

Originally Posted by davepl

\
If you're at all worried, pay someone to do it. As I've said before, good brakes are cheap life insurance and you should save money elsewhere when in doubt.

I 100% agree. For me that was having my front end re built by a reputable suspension shop. Had to swallow my pride a bit, but theres something to be said for the peace of mind in knowing its right at 70 MPH. Brakes and steering might not be as sexy as 20" billets, but they're without a doubt more important.

I also wish there was a shop like that near me!

[kwmech]

I could have that threaded into the block in less than a minute. Loosen things up and do a little tweeking. The lower lines you will have to cut back and splice in. You can install a plug in the upper port for the front line. Is that teflon I see at the master cylinder fittings

[ERASER5]

I think that is just shiny metal, but to be sure, NEVER EVER use teflon tape on brake lines. The threads are only holders. the seal is at the matching flares.

I think I would pull and bend those lower lines into place, unless they are too short. My luck, they would be 1/2" too short. As far as the lines from the MC to the block, push/pull, tweek and force it a little. Starting the thread straigh is paramount, if the tube is a bit crooked, it will flex into place. It's just the way it is. X2 on plugging the upper hole. The "T" at the frame will do exactly the same thing.

[davepl]

I once saw a guy use RTV on a brake line. It was the rubber flex line. It had an inch or so split in it, so he rubbed RTV on the outside.

It didn't hold. Something about thousands of PSI of hydraulic pressure.

To re-itterate what ERASER5 said, remember that any flared connection is just that: it's the interface between the flare and seat that seals. The threads do absolutely nothing but hold the two together. They could be luggage snaps instead. Putting a sealant on the threads does nothing. Nothing useful anyway. And there is literally no amount that would work. So I don't mean it doesn't work well, I mean it doesn't work.

[Artikgrau325is]

So I'm thinking to myself, this is either going to be successful, or a complete disaster. I brought my old lines in with the prop valve to the local Napa. An older gentleman there spent quite a bit of his time helping me find the right lines, fittings and adapters I needed. I bought two sets of lines just in case.



Turns out it was a whole lot easier than I thought, almost enjoyable even. I tried using tie wire to mock up bends under the vehicle to transfer to a new stick, but it was far too flimsy. It was a bear wrestling a 30" piece of tube and bending it underneath the truck. Better planning could have avoided this.

I also learned to tape the fittings at the end of the pipe. I probably bent things 3 times not realizing that the fitting had slid down and would not get around the bend anymore. Overall, good stuff. Not as scary as I thought.

Also, there's no Teflon tape on the fittings, so no worries there.

[chevy72blu]

finished product looks great