**FAQ** Braking System Component Install

[david58]

http://home.comcast.net/~southcross2/VW ... ersion.htm
The info you want is here I tried to steal the charts and post them but they got them locked down tighter than well you know............

[Leatherneck]

Just have to know how to get in.


Front Calipers:

10mm x 1.0mm thread (female)
Typical AN size for brake lines:
-3
Rear Calipers:

10mm x 1.0mm thread (female)
Typical AN size for brake lines:
-3
Bleeder Screws:

7mm x 1.0mm thread (female)
(while not an AN upgrade, good to change to speed bleeders)
Chassis Hard Line Fittings:

10mm x 1.0mm Metric Inverted Flare (male)
Fuel Hard Line Fittings:
Rear Chassis

Metric
Fuel Hard Line Fittings:
Engine Compartment

Metric
Common AN Sizes:

(increments of 1/16")
AN Size

Fraction

Decimal / Metric
-3 3/16" .1875" / 4.7625mm
-4 1/4" .250" / 6.350mm
-6 3/8" .375" / 9.525mm
-8 1/2" .500" / 12.700mm
-10 5/8" .625" / 15.875mm
-12 3/4" .750" / 19.050mm
-14 7/8" .875" / 22.225mm
-16 1" 1.00" / 25.400mm
Common Usages:
-3 Brakes
-6 Fuel Return Line
-8 Fuel Feed Line

[david58]

Here is a good site with a lot of info on fittings and adapters.
http://www.fittingsandadapters.com/metfitfincha.html

[DesertGuy]

Concerning the hardline... are most folks buying "pre-determined" lengths already flared, or is anyone making their own flares. If so, which tools are needed and which type of flare is it.

[Leatherneck]

With the big assortment of sizes I meausred and bought preflared . Also didn't have to go " oh dammit forgot the fitting"

You do have to make sure the flare matches the corresponding fitting or adapter though.

[bajaherbie]

i bought pre-made hard lines from the FLAPS store. got pretty lucky on the lengths being what i needed....

[Plam 1]

Wow,
Thanks for all the replies. Seems like a lot of people out there had the same question on their mind. So if I got this right, 10mm x 1.0 is the correct fitting into the wheel cylinder ( not the caliper ) and just get the an3 end to fit the stainless hose. Goes like this:

Wheel Cylinder adapter 10mm x 1.0 male to -an3 male
Hose -an 3 female both ends
Hard line adapter 10mm x 1.0 female with -an 3 female

Any additional sealing washers needed for this setup? I have read that the an fittings might leak if not seated properly. Is this only if you make your own lines?

A brake hose bender allows you to use the premade lines and make them look as if they were meant to be that way.

In the words of that Cable Guy " Correct me if I am wrong."

Thanks for the help and that pic of the lines attached to the beam sheds new light on how to run the lines. Only question was did he use a 45, 90 or straight fitting coming off the brake side? A pic would help.

[Skidmark]

When you look at the pic of my M/C's I think you can tell which way I went with that one...

I have a few friends that bought the tools to do their own flares, but I didn't want to go through the hassle... they had several leaks to redo before they got good making their own flares. Not sure which tooling is better, etc...

[DesertGuy]

Does anyone have any "tricks" when it comes to bending the hardline.

Here is a pic of my old set-up. This worked fine, just changing things around a bit.

[Getrdone]

Desertguy, The cheesey looking spring thing that looks like a chinese finger torture toy is handy adjunt to a hand madrel bender. It lets you bend complex curves and angles without kinking. Have'nt seen many lately though. P.s my double flare tool I used on my domestic projects does'nt work. It is the common everday job.

[fusername]

Well I just finished routing my hard lines, and I found out that the best way to make some damn pro-looking bends is to use your frame! It takes a good handle on which way to push to avoid kinking, but you get the hang of it pretty fast. Just use the biggest diamater pipe on your rail (you are working on a rail, rihgt?) and work the line around it, SLOWLY, watching closely for it to kink. you need to slowly adjust the direction you are pushing from, otherwise it bends all in one place, and then the kinks start. It is impossible to expalin, but once you try it you will figure it out. start on a hardline you already messed up tho, because you will do it again! Once you know what not to do, it gets easier.

now here is what I have no clue about. I bought a NEW german M/c, I think it says FAG on the side, and I have 4 wheel disk kit i bought from empi before I knew any better. now that I am out of money but no where near done, I have scaled the budget back a LOT.
How do i figure out what size pistons I have? do i pull somehtign out and measure it, is there a better/smarter way?

so far, all I can tell is this - 2 lb residual pressure all around, close to M/C as possible. somehow weaken front braking power.

does anyone know how i can geta cheap (used?) presure proportioiing valve? If i bought one from a junk yard, out of an old pickup, it would have all SAE fitting,s and that wouldnt work. what have other people used? my FLAPS doesnt even have metric T fittings, so I am all allone in the norht east it feels.

[Ol'fogasaurus]

If you notice by the chart that was given, that AN fittings are based on 1/16ths. Most all, but not all (SAE) standards are sized that way.

The residual pressure valve is required (should be used) when the master cylinder is lower than the slave cylinder/caliper. This is like Leathernecks said, to stop brake fluid from siphoning back into the master cylinder. The pressure holds the shoes/pads close to the braking surface where if the fluid pressure left the cylinder and line the brake would take longer to energize. If the pressure drop was bad, it could also cause the brakes to be "pumped up" before full pressure could be applied. The rule of thumb is disc brakes require a 2# valve and drum brakes require a 10# valve. I have heard a couple of builders say that they use a 10# valve for both discs and drums.

If you have your turing brakes higher than your rear brakes (at rest), you may not need the valve between them. You could need a valve at the master cylinder though but this also depends on where, how you mount the M/C. It is not a bad idea to put the valves in when building a new braking system rather than retrofitting them. For most of us, the master cylinder is lower than where the slave cylinders inlet is and a valve should be added especially if your buggy sits a lot.

I think I saw something on proportioning of the cylinders. A porportioning valve only slows down the action of filling the slave cylinders. The volume of the cylinders never changes so the pressure they exert never changes. You can just slow down their application by the porpotioning valve.

Putting the front wheel cylinder in the rear is an old trick (see Baja Bugs & Buggies by Jeff Hibbard). As I understand it there are three sizes of wheel cylinders; "stock'68 and later rear wheel cylinders -17mm , 19 mm wheel cylinders, and Type 3, 22mm wheel cylinders. There are also some after market wheel cylinders" (this information is per Jeff Hibbards book) I don't know how you determine which on to use but I suspect most people always go with the biggest one.

Hope this helps.

[ntsqd]

First I've seen of this thread. My various responses below:

... I would go with Dual M/C, hard lines except at pivot points where stainless braided will be used, both a Residual valve even if does not seem like it was required at the time and a proporsioning valve for fine tuning brakes...

If you have a true dual m/c system with a balance bar pedal assembly you do NOT need a proportioning valve. P-valves are only needed with single or tandem m/c's like the OE parts.

Dual master cylinders - I have a CNC pedal assembly with a balance bar and two 3/4" master cylinders. After looking at the set up more closley, and asking some shops, I found out in order to bleed the front or the rear brake system you need to remove one or the other plunger in order to bleed the opposite system.

Never heard of this in all my racing and brake design experience. The balance bar can only go so far and then it's travel is limited out by a feature of the pedal itself. Might not have full stroke, but it shouldn't be all that hard to bleed. They were bench bled b4 installation, right?

I was actually talked out of going with a line lock by one of the guys at McKenzie's. He had personal experience troubleshooting a brake pressure problem on a customer's car, and after checking everything out they ended up replacing his line lock. It cured the problem, but only for three weeks and the problem came back. The customer ended up removing the line lock from the system and had no more troubles. Word from McKenzie's is they are not reliable and fail too often. Their recommendation - carry a good wheel chock in your car (if you can't put in a mechanical parking brake).

It is a not so well known fact about those Park-Loc units that they bleed down over time. This is not a bashing of their mfg, all hyd systems bleed down over time. This is why the FMVSS requires a mechanical parking brake mechanism.

Skid, why no residual valve in the plan? How noticeable it is I do not know but the higher percentage of flexiable line the softer the pedal can be if not now then as expansion and contraction happen.

I've twice plumbed a race car entirely in -3 braided stainless hose. The second was a Drag car. A little flex there isn't a big deal. The first was done at the insistance of the owner/driver. This was a IMSA Showroom Stock Mazda MX-6. It won it's class national championship that year, so it couldn't have been too flexy.
Now if you were talking about using the OE type rubber hose, that would be ugly.

....I am using -3 AN fittings on the braided lines. When I measure ove rthe top of the braid they are .25" in diameter, but I don't know what the I.D. is (-3 AN should mean something here, but in my case it doesn't!).

Short course in AN (& JIC) sizing lingo: A 'dash' number is how many 16's of an inch the size is. When in reference to a screw or bolt it's the shank's OD. When in reference to hose it's in reference to the ID of the hose. Note that this isn't an exact size when dealing with AN hose, it is an approximation.

...I had Torino Motorsports make up the lines for me, after I determined the length for each one.

It's done now, but I prefer to make my own. There are some who claim that the crimped lines are better. They've never taken one apart. The crimpers have a puny, tiny little tube that connects the swivel nut & conic seal part of the fitting to the hose. In off road applications it is exceedingly easy to break these off. Then yer skrewed.
Contrast that with the much larger layout of the screw together type hose ends. A bonus of the screw togethers is that they can be field repaired. Oft times all you need is a new 'berry'. Odds are you'll be leaking blood from your finger tips, but you'll have full hydraulics! The spares I carry for brake hoses is one section of hose equal to the longest section and one of each unique type of hose end. With those parts you can field repair any of the hoses on the vehicle.

.... You can flare the pipe with the 45 degrees flare by annealing the end of the line. The annealing will make the line conform to the 37 degrees. The pipe will bend without annealing.

This works, but it really makes me nervous. If we were talking dead soft aluminum tube then I'd have no issues with it and have done it. Repeatedly. Stainless is another critter & I won't go there.
Stainless work hardens very easily. Even if it doesn't crack right away it can down the road. It's not that much $$ to get the proper 37* flare tool. Search McMaster for p/n 2691A14 Even though it says it's for soft metals I have used it on non-annealed 304 SS tube and it works fine.

Drill the SS lines if you use a pipe cutter. The line must not be rolled in before you flare.

I always use a Mechanics' Taper Reamer followed by a 90* Countersink on each tube cut end. It also is exceedingly helpful if the cut is truly square. Flaring a unsquare end usually results in a split or crack.

Why so many fittings. The clutch could be ran in all hard line.

Agreed, but only if there is a loop at the slave cylinder to allow movement w/o working the flares to fracture. FWIW I usually prefer to plumb clutch systems with 1/4" or -4 tube/hose. This is b/c those systems typically move a lot more fluid volume than a brake system, and the operating pressure is much lower so the system doesn't not flex like a brake system done in 1/4"/-4 would.

It is common in desert racing buggies to zip tie the front brake hoses to the tie rods. Usually the right hose starts out pointing to the left either above or below the rack and makes a large radius loop onto the tie rod.

Depending on which actual size being bent I use a Rigid or Imperial Eastman size specific tube bender. Those 3 sizes fits all tubes benders aren't worth the potmetal they're made from.
For large radii bends the "bent over a tube" method described above is the best. For standard radius bends the size specific benders I mentioned above are the only way to go. Now what if you need a bend *RIGHT* behind the tube nut?
One of my bosses in my racing prep days showed me a tool he made for this. It is a piece of bar stock drilled & tapped in the end for the tube nut threads. The trick here is to use a bottoming tap, drill the hole fairly shallow, and risk breaking the tap in getting the threads all the way to the bottom of the hole. When the tube nut is tight in the bar stock the tube itself should not be able to wobble about at will.