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Brake line modification tech.....

In many 4WD vehicles the manufacturer locates the front brakes lines in a location that is ok in for the boulevard wheeler, but not very good for those of us who actually take the roads less travelled.

What I am talking about is when the brakes hoses run from some point in the wheel well, where they're usually attached to the frame or inner fender, and run down to the brake caliper. When a 4WD that has its brakes hoses set up in this manner, and it's used for fourwheeling, the lines usually get pulled tight... too tight in many cases... and necessitates the need for (much) longer brake hoses. If your 4WD is lifted, then it's almost a given that you're going to need to buy longer ones.

I've been saying for many years now that it is much better to spend a little more time, and about the same amount of money, and relocate your brake hoses to prevent them from doing the guitar-string-thing the next time you go out wheelin' than to just replace them with longer ones.

This tech article will present you with the basic concepts that you need to relocate your front brake lines to a more advantageous location.

==============NOTE===============

I must add bit of a disclaimer here, before I get going.

Making changes to your braking system can seriously affect your vehicle's ability to stop safely.

Any modifications to your braking system must be done by a competent technician who has experience with and understands the idiosyncrasies of your particular braking system.

These modifications may not be suitable, as presented, with some braking systems, including ABS braking systems. If you are in doubt, be absolutely sure to talk to someone who is competent and understands the braking system in your vehicle before you make any changes to it.

If you are in doubt, DO NOT make any changes to your braking system.

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The basic concept is that longer brake lines are not only expensive, but they are not the best way to fix a problem that might be better solved in another manner.

Also, longer brakes lines can do all kinds of annoying things like rub against body or suspension components, or tires, and eventually rupture. Over the years I have seen this exact thing happen numerous times: a brake hose rubbing against a tire wears through and ruptures, overly short brake hoses being pulled out of their fittings or mountings, overly long hoses getting pinched between nearby parts... Sometimes the trail fix is easy, and other times it is not.

The idea behind relocating your lines is to move them from their present wheel well to caliper routing and change that so that they run from the caliper down to the axle. Once the hoses go to the axle they are routed along the housing to a T-fitting and then another hose is added so that the lines then follow an arc similar to that of the arc of the spring and then up the the frame. When routed in this manner (see photos), as your suspension articulates, the effective length of the brake hose does not change very much. If you attach the lines in an optimal position you will find that the amount extra length needed is not all that great.

The photos show quite clearly the changes to the stock system.

[fig 1 overview of left front wheel well with changes made]

[fig 2 close up view of the same front assembly]

Note that the hose was positioned with the factory bracket and clip that was removed from the frame and reattached to the axle housing.

It's important to check that the brake hose must not get twisted and can steer through the full range of steering without pulling tight.

[fig 3 close up view of the left front assembly from the back side]

The brake hose is securely attached to the housing and steel lines are make up to provide adequate clearance of the u-bolts, springs etc... The steel lines must not rub against or vibrate against any objects. Steel lines that are free to move around, or that vibrate excessively will work-harden and crack or break off... and that would be a bad thing!

[fig 4 close up view of the right front assembly from the back side]

[fig 5 & 6 close up view of the left front assembly showing clearance allowance of other parts]

[fig 7 shows the steel T-fitting that is used to join the steel brake lines. This part comes from a Land Cruiser 60 series rear axle]

[fig 8 all the steel lines are secured with rubber insulated ties that are bolted to a secure part of the housing, which in this case is the axle truss. In other cases it's possible to weld a small bolt head to the axle tube and then attach the ties with a nut on the end of the stud that then protrudes out. When bending the steel lines, make sure that you use a tool to make smoothly radiused bends. If a line becomes kinked, it should not be used. New flare nuts are available at auto parts stores and make for a very clean installation rather than reusing the old ones. Be sure to use a good double tapered flaring tool to make all flares.]

[Fig 9 before figuring out where you're going to attach the new hose, you should force the suspension to it's maximum droop so that in a real world situation you will know that your new hose is not going to be pulled tight. In this case, I used a bottle jack between the frame and the spring plate to extend the suspension.]

[fig 10 with the suspension forced down it's now possible to experiment with optimal brake hose mounting locations. It's best to run a line that is just long enough to get the job done and not much longer. The vertical wheel travel in this Samurai is about 11" and the articulated travel measured at the wheel appears as though it's going to be a little more than 16". The brake hose is about 15" OAL and is plenty long enough when run up at an angle. If the hose was attached in the stock location it would need to be in excess of 20" long.]

[fig 11 once an ideal location is found, the brake hose bracket is welded into place from the front side. Welding from the other side leaves open the possibility of welding spatter entering the fitting.]

[fig 12 the brake hose and line in place and attached. Note that in this situation, the extra opening left over, from the one line that was removed, on this distribution block needs to be blocked off with a plug. ]

[fig 13 the brake hose is position with the suspension forced at maximum non-articulated droop.]

[fig 14 the brake line with the suspension sitting at normal ride height.]

[fig 15 a healthy dose of Rust Not over the exposed metal to prevent corrosion]

When you have completed your changes you will need to properly bleed your braking system and then check all the connections for leaks while they are under pressure.

Stay tuned as I will soon be adding more information for those who have dual diagonal braking systems.

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I will add some more to this article soon.... it's late now and I need to get to bed. I need to address the issues of dual-diagonal systems etc... so please leave a "more to come" thing at the end of the article if you get around to posting it before I send you the next section to it.

John Barron--Victoria, BC, Canada