I'm fixing up an old dakota I had laying around; I thought I'd start a thread to get insights and help as I progress through the repairs.
The backstory is that the Dakota got grounded a few years ago due to a brake problem and since then the issues have stacked up... a poor windshield seal ruined the interior, the shocks gave out, the brakes continued to rot and more. Rationally speaking I should have cut my losses and sent it to the junkyard, but it is a bit sentimental and I already have spent too much money to turn back now.

The first order of business was making the interior at least habitable. The vinyl floor was so wet and rotten from the leaking windshield that there was mold and even maggots growing in it. The plastic panels and dash had also started to rot due to the sun, water and mold. So, I completely ripped everything out of the interior. (See initial pics). Then I discovered that there was some rust on the driver's side floorpan. The proper fix would have been to weld a new panel in, but since there were no rust holes I just ground it down, applied some rust remover and then painted over it with rust stop compound. I'm having the seat reupholstered and I'll figure out some way to cover the dash.

On the mechanical side of things, first I replaced the shock absorbers which were totally shot with some new KYBs. Next I did some basic maintenance like oil change, filter changes, coolant flush and ps flush. I repainted the radiator fan and airbox with some engine enamel to cover up the rust on them.

The big battle that I've been in is with the brakes. I started out only replacing the rear brake drums and shoes, but then I discovered a leak in the rear brake line and had to fix that. Finally, I tried driving the truck but the front calipers were rusted on. I tried cleaning them up but it didn't work so I had to replace them. After that, I found a leak in a flex line so I replaced them, but I damaged one of the steel lines in the process. Now, I've decided just to replace every inch of rusted steel brake lines on the truck and the portioner and I am currently in a frenzy of cussing and busting knuckles to get the old lines off.

My only questions at this point are:
- Is there a diagram of the brake lines available? I may have bent some of the old lines too much to use them as a pattern.
- Can you buy a new portioner valve? I can't find them for sale at any of the big auto parts stores.

 

A factory proportioning valve? Not any longer new.

May find one in the boneyard.

Or, there's the adjustable ones from, say, Jegs or Summit or other sources ... https://www.summitracing.com/search/...tioning-valves for one possible source.

As to the brake lines - not that I'm aware of, but it may be close enough if you pick up a full factory service manual (see the sticky here; there's several there that may or may not be usable) and work from there.

I'd suggest that doing the cab off for this may be easier ...

OH! While it's apart - I'd HIGHLY recommend some sound deadening. The canonical brand is probably Dynamat (tm); I use a generic work-alike.

It helps keep the cab warm in the winter, cooler in the summer, and quieter overall.

RwP

 

I redid my entire brake system with all new lines. Highly suggest using the OEM in-line flare tool....I think Ralph initially turned me on to that solution, and it works flawlessly: https://www.summitracing.com/parts/o...iABEgLkt_D_BwE

As for the proportioning valve, you can't buy them new, BUT you can buy the summit 760185 which is actually a PV-2, which is the pretty much the same thing only in brass. It does have one extra front brake port on the bottom that you would need to plug, or if you are running all new lines anyway, use both ports and get rid of the front Tee. I have one I don't need if you want to purchase it at a slight discount. I have the pigtail, the blocking adapter for bleeding and the valve. https://www.summitracing.com/parts/sum-760185

I used my old lines as a template, but even then, deviated somewhat where it made more sense to me. If you need a picture of a specific run, let me know. You didn't mention what year Dakota you have, but they should be pretty close. My 90 (87-90s) have the prop valve on the frame rail under the cab. The newer Gen I (91-96) may have moved them up into the engine bay...not sure.

 

wont need a new proportioning valve. Don't need a diagram of the brake lines. don't have to be "exact" identical lines to original, just get them close. DON'T DON'T DON'T use compression fittings on brake lines.

 

Dang, reminds me A LOT of mine, and yours seems to be snowballing in a similar manner. Good work so far, nice you were able to save the floor for the time being.

As others said, don't worry about matching the lines exactly. Follow the general path, keep it away from other metal, secure it well, and be a little generous with the line to allow for flex and vibration between the body and frame.

A good flare wrench will help you get stuck fittings off.

 

Well, I finished putting all the new brakes on. New back drums, shoes, springs and new front calipers plus new front and back brake lines all around. Did not replace the brake lines going from the front to the rear proportioner or the rear flex lines but everything else is new. The copper nickel lines they have now make bending brake lines a lot easier, and they don't corrode like steel lines. The only problem now is there may be a problem with the booster or maybe there's some phantom air in the lines. I bled the lines out twice to be safe and I get no air coming out of the bleeders, plus the pedal feels firm. But when I turn the engine on the pedal goes to the floor. I thought it could be a vacuum leak so I replaced all the vacuum hoses but it didn't totally fix the problem.

 

Pedal to the floor when vacuum is applied means that a diaphragm in the booster is bad.

See, there's two vacuum sides; one to pull down, one to release.

The release diaphragm is blown, so the apply is all you're getting.

BIG hint: normal cause of the booster failing is the master cylinder leaking into the diaphragm, causing the rubber to fail.

I'd plan on both the booster and the master cylinder.

While assembling, paint the booster; mine was unpainted, and it looks horrible rusting like it is.

Also, adjust the push rod BEFORE assembling the two together if you buy separate.

RwP

 

On first glance, sounds like the Booster as Ralph suggested. I just replaced mine AGAIN this weekend. As a warning, it's possible to buy a booster and it be bad out of the box. Happened to me. All the boosters nowadays are remans, and since ours aren't in high demand, they sit on the shelves forever, and the seals rot.

Also, from my personal experience, swapping the two lines at the MC can also cause the pedal to the floor. The front line (closest to the firewall) is for the front brakes and should go to the front of the prop valve. The back line (closest to radiator) is for the rear brakes should go to the rear of the proportioning valve.

Lastly, a bad check valve on your booster can cause pedal to floor. Easy to check, remove the vac hose and blow into the port on the valve. If you can blow into it, then the valve is bad. Mine was bad on my original booster. Another FYI, it's hit or miss whether your new booster will come with a new valve. The 1st booster I bought did...the second one did not, and it's not an off the shelf part the local auto parts store carries. Also, in regards to paint, the 1st booster I bought was unpainted, the second was painted...so also hit or miss. But paint it as Ralph suggests if it isn't. I just used some flat black engine paint.

For the rod, i use a micrometer, and measure the height of the rod on the booster I'm removing, and set the new one the same. That's assuming your first booster had been working. If you don't know, there's a procedure in the FSM, but it's basically adjust it out until you feel it touch as your putting the MC onto the booster, then turn it back in one turn. That'll give you about 1/2" play on your pedal.