Help - leak in main brake lines

[BonesDT]

HELP!!!

I just bought an '89 Dakota (RWABS), which I'm restoring. I just installed all new rear drums, front discs, shoes/pads, and front hoses. I then bled the system.

When I went for my brief test drive, the brake pedal went down to the floor.

There is a bad leak by a 3-way junction with rusted brake lines going to it.

How do I fix it? How do I know if the junction needs to be replaced, or the brake lines. I guess I should replace all the rusted brake lines in the truck.

Do I have to get it professionally done? How much am I looking at?

 

[IZwack]

You can replace the lines yourself. Getting "hard" lines and flexible lines is easy enough and they are available at most parts store.

Did you touch this junction at all? Like unscrewed lines from it? If you did, my guess is that the connections are just not tight enough. But if you can, you might as well replace things since you describe them as being rusty.

BTW, before your next test drive, pressure test the brake lines first for a few minutes and make sure they dont leak Otherwise you could wreck your vehicle.

 

[BonesDT]

don't you have to bend and cut the "hard" metal lines yourself though? or can i get them pre-sized/shaped specific for my vehicle? is this a dealership only part?

can i replace the "hard" lines with flexible lines? i always wondered that. or are the flexible lines just at the wheel corners?

no, i did not touch this section at all. what's scary is that I've been driving this vehicle for over 200 miles. I'm guessing the bleeding put the stress on the weak area. of course, I'm glad it happened during bleeding rather than the highway.

 

[IZwack]

You can get pre-bent and pre-shaped "hard" lines at the dealership. If you go with ones at the local parts store, they of course wont be pre-bent or pre-shaped. But "hard" metal lines can be bent with your hands, but you have to be very careful and not kink it. A bender would of course work better but sometimes you cant get a bender in tight spots. If the line you get is too long, you can either put more bends in it to take off some of the excess, or you can cut it and re-flare it using a double-flare tool. The practice is easy but making a good double-flare is more of an art and takes patience.

You can replace the "hard" lines with flexible lines but the more flexible lines you have, the "spungier" or softer the brakes will be. It is wise to minimize the amount of flexible lines on highway-driven vehicles.

As for that junction thats bleeding, try tightening whichever port is leaking. It may just require an extra 1/4 of a turn to stop the leak. This is a short-term fix and you should definitely replace whatever is causing the leak.

 

[sav's trac]

when i turn my steering wheel all the way to either side an i press down on the brake, their is no pressure behind it! what is the problem?

 

[BonesDT]

That's wierd. The only way I can think the steering is connected to the brakes is through the vacuum to the brake booster. Maybe full steer is affected the engine vacuum somehow, but even so, no vacuum to the booster means you would feel lots of pressure like pushing the brakes when the engine is off. Beats me. It seems like full lock steer on a lot of vehicles enters this quasi-world of physics that does all sorts of wierd unexplainable things.

btw, I fixed my brakes by replacing all the brake lines in the truck, one of the old rusted ones popped near a tight bend. I used pre-cut pre-ended lines in different lengths from my parts store and bent them myself. Bending = very easy; actually tearing out the old lines and installing new ones = PITA. Thanks for all the help.

 

[Texan01]

Keep in mind on your Dak that there may be a load compensator attached to the left leaf spring that reduces brake pressure to the rear brakes under light load, you have to disconnect the spring that attaches to the suspension to get full pressure to bleed the system properly.

My knowledge of Daks is limited to the '87 and 94 years as dad had both of them. they are good solid trucks.

 

[sav's trac]

quick question.. when i turn my steering wheel all the way to either side and i apply my brakes, their is no pressure backing it up. it just happens when i turn all the way though.. im thinking mabe a kink in the front lines?

 

[sav's trac]

i did notice it after i did the TT. could that b a problem?