Bad day on brakes..........

[Torxhead]

Ditto, with what everybody else said, and best of luck.

 

[Hedgehog]

Update - finished installing the brake lines. Reverse bled the brakes and ...... Nothin' ..... as in nothing wrong here. The brakes bled as expected. .......... wait ...... ... This thing has brakes, man oh man does it ever have brakes, breath on'em and you stop, you stop RIGHT NOW! Very little feel.

So, now the problem is too much braking power. So, how does one reduce braking power? It seems to brake evenly enough. Solid front brakes, even solid rear brakes. Driving on packed dirt it was easy enough to get consistent 4 wheel skids. Of course that was pushing the brakes hard.

Driving with the different front end is dangerous at highway speeds. I need to have the thing aligned.

4wd with the new Tru-track is so solid it's scary. I tried but was practically unable to spin the front tires. Yes, in mud or very soft dirt all is possible, but the tru-track preformed as expected. GREAT

 

[jammer1]

I've got a CJ7 with fiberglass body, 33" tires and a vanco M/C (corvette style) and a power booster. I understand what you say about how easy it is to lock the tires up. First time I took her on the freeway and had to do a near panic stop I had her starting to go sideways. Almost scarred the shi** out of me. Had to learn to take a mental note to just tap the brakes not hit them like I do with my work trucks. Wet roads are the worst. Set up I have should probably be for 35" tires. Just be careful. Glad you have brakes now.

 

[Hedgehog]

Problem is, there is NO real resistance and I simply don't have that much control, especially when braking and shifting at the same time. I'm going to lower the pedal a bunch, it was too high, now it's high and dangerous all at the same time. With the pedal rock solid on the bottom of it's stroke there is 4"-5" of clearance to the floor. I'm thinkin' of a 2" lower pedal.

I think I'll call the "All Shebang" folks and see if there is a way to adjust the booster.

 

[jammer1]

Mine pushes down easy (virtually no braking) to about 1" above the gas pedal. Then the brakes grab and I have only 1 to 1 1/2" to petal is completely down and brakes lock. This is around 3" over the floor. Don't know of a way to reduce power of the booster. Usually the m/c has a lot of the control. an example is if the m/c has a 1 1/8" bore it's harder to push the petal to stop (pushing more fluid with less petal travel). A 1" bore you have to push less but the stroke (petal travel) is longer. I've heard to reduce the power of the booster you have to get a smaller diameter booster or go from a dual booster to a single booster (same idea, duel just makes it a smaller package).

 

[Hedgehog]

Mine has about 2" of travel with little feel, but that doesn't mean it isn't braking and braking somewhat aggressively. When the peddle starts to firm up the CJ is stopping in a big hurry. Darn I hate to tear this thing apart yet again. Gotta do what you've gotta do. At least I know the actual brakes work well.

 

[Bent]

I had the same problem when I converted My 66 Barracuda to power disks. The wheels would lock up with a light tap on the brakes. I ended up using an adjustable proportioning valve. I was able to get it dialed in real nice. Wish I still had the car.

 

[Lumpy Grits]

Hedge-New disc brakes are very 'touchy' till broken in, some 200-300 miles of driving.
Also, you now have power brakes to get use to.
Welcome to the 21st century-------
As far as the front end. Confirm your tire psi is the same. Different psi means different tire O.D. That will cause issues with a true locker.
LG

 

[Hedgehog]

Lumpy - It's a truetrac = a Limited slip or this one:

No problems with it. I'm very impressed with it. Very neutral feel when driving, no cornering issues. Stub up against something and the CJ either climbs or stalls. Can't hardly get the front wheels to spin on fairly loose dirt. Now remember this was a very limited after working on it test run. I'm impressed so far.

When I'm talking about touchy, I'm talking about head in the windshield darned near dangerous. Mostly because my brake foot is entirely in the air with nothing to give it feel. For instance a car brake pedal is closer to the floor giving you the ability to set your heal on the floor while braking. Braking while turning and shifting is a frightening situation.

 

[Woolyworm]

Glad you've got brakes. I can't wait to have the $$ for a truetrac but I'm putting one in the back. I've heard great things about them.

I recently installed a dual diaphragm with corvette type MC and have the same type of braking as described by folks here. I got used to it in a couple of weeks. I'd still like to drop the pedal another inch. I'd rather have what I do now than what I had before which was no lock up ever.


Wooly

 

[Lumpy Grits]

I've installed many TT diffs and thou the are advertised as a LSD.
Both sides are very easily engaged. Takes very little difference in wheel rpm for the worm-gears to lock(bind)to give a 'solid' front axle.
You made a very good choice for the front.
How much pedal return spring do you have on that brake pedal?
LG

 

[Hedgehog]

I've got what ever came with it, I imagine it is stock. Yes, I've considered getting a much heavier spring.

Wooly - I did get lucky on both the Rear E-locker and the truetrack. Within days of each other they were on Craigslist. Got the E-locker and the truetrack, both New in the box for less than I would have had to pay for the E-locker alone. I think I was lucky because I was going a non traditional way. Most guys doing this are heading in the 4.11 direction rather that the 3.31 direction like I was. I think both fellas realized that they needed to regear with different carriers and dumped their mistakes off for cheap. Fortunately I knew what was needed before buying.

 

[Lumpy Grits]

If the return spring is a expanding coil type. You could add a second spring by going to a larger one that slips over the stock one or you can go with a smaller OD spring that slips inside.
LG

 

[jammer1]

Hedghog, do you have a adjustment on the rod that goes from the brake pedal (arm) to the power booster (inside of firewall) There are different versions. If it's threaded can you unhook the rod (eye end that's on brake pedal lever) and screw it in toward the booster. This would drop the pedal down some. You have to balance this so you have it stop with the pedal height up to your liking yet low enough where you may have a heal on the floor. Mine if I drop the brake pedal height down then it bottoms out below the gas pedal and I don't like that so I live with the brake foot up in the air.

 

[Hedgehog]

Lumpy - I will look into that.

Jammer - My booster is one of those with a linkage inside the firewall between the wall and the booster. The adjustment inside the jeep body is already bottomed out for the initial adjustment. But, there is an adjustment on the linkage outside the firewall. I'm going to look into that. One thing that concerns me though. I don't want the pedal stop to be at the end of the pedal movement, I want it to stop on the swing pedal bracket. Probably a welded bolt or something similar for a stop.

With my pedal absolutely bottomed out, skidding tires on pavement, there is still 3 or 4 inches to the floor. Some guys actually extend the pedal toward the floor, that might be an option. Both the brake and the clutch could easily be closer to the floor. that would be welcome too. It's not just the height of the pedal, my thigh hits the bottom of the steering wheel when on the brake. Kinking the leg and knee sideways works, but is hard on the knee joint and I suffer for it the next day. It sounds like nothing but problems, it's really not that bad. Just an annoyance is all.

 

[tarry99]

Mine has about 2" of travel with little feel, but that doesn't mean it isn't braking and braking somewhat aggressively. When the peddle starts to firm up the CJ is stopping in a big hurry. Darn I hate to tear this thing apart yet again. Gotta do what you've gotta do. At least I know the actual brakes work well.

Did you ever check the pedal ratio as I once mentioned?............you went from non-power brakes originally to power now...........non-power pedal ratio is about 6:1 , power ratio is about 4:1..........will that make a huge difference in how aggressively it stops? .....Yes it will.............also the linkage adapter between the firewall and booster can also effect that ratio........

 

[jammer1]

I forgot that you have a CJ5 , I have the CJ7 and it came with a automatic. I have the same problem with height of pedal but countered some of it by moving the seat back (seat mount) otherwise I was hitting my knee and on breaking would have my foot go under the pedal during breaking. Screwing in the linkage adapter changes the height (starting point) and ending point of the pedal not the leverage because the mounting point is the same (in both screwed in or out and the travel of the pedal). Changing the mounting point of the linkage (on the brake pedal arm) changes the ratio (leverage) used against the m/c. On my brakes I originally had manual and switched to power. I have a manual brake arm/pedal sitting at the shop to try and see how much it would change just never got around to installing it.

 

[Hedgehog]

Tarry - Yeah, I know there is all kinds of math that can be applied. But frankly I ain't going to do any of it. I relied on a company that specializes in power brake conversions and this particular one isn't an uncommon one. I do know that there were two brake pedals, one for a power brake and the other for a manual brake. I'm going to see if I can find one for a power brake system. Or at least find out what the difference is between the two.

 

[tarry99]

Tarry - Yeah, I know there is all kinds of math that can be applied. But frankly I ain't going to do any of it.

Hey , No Problem drive it the way it is...........and there was never two Brake Pedals........the difference is where the push rod was located. Some Pedals had two holes , some had the extra hole blocked with a stud for the brake return spring.

The fact still remains:

Pedal Ratio is one of the most overlooked parts of a brake system. One of the main reasons and causes of a hard brake pedal or in your case a sensitive pedal is simply due to incorrect pedal ratio. When a brake pedal gets modified to “fit” in a vehicle or a booster/master cylinder gets installed where it “fits” in the car, the pedal ratio is rarely taken into consideration. Proper pedal ratio is a must when installing and operating a brake system. Below is a diagram to show how to properly figure pedal ratio:

Pedal Ratio = X divided by Y
In a manual brake system, the pedal ratio will be between 5:1 and 6:1 and a power system will be between 4:1 and 5:1.
If the correct pedal ratio is not achieved, the pedal will be extremely sensitive due to too much pressure being applied too quickly.

 

[Hedgehog]

Then why are there two part numbers?

The math: Yep that looks like math all right...... I do understand how different ratio's effect the way your brake pedal feels.

If the "Y" distance can be found, I'll run with that.