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Unread 02-10-2013, 08:15 PM   #16
ZJMatt
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Quote:
Originally Posted by Pugulis View Post
Just a silly question. How's your vacuum pressure? Or more specifically is the check valve on the brake booster connected and working? I had a bad check valve on a car years ago and it did the same thing.
Tested the check valve (by pulling it off and trying to blow through it) today. Forgot to report on that - it's good.


I guess the next step is to pull the master cyl off my parts jeep (which also went dry...), bench bleed it, and replace mine with that.

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Unread 02-11-2013, 03:02 PM   #17
gabrod72
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Shot in the dark here, but did your 95 have drums rear? If so, did your new axle also have drums? Reason I ask is when I swapped my 1993 rear D35 for an 8.8 with disks I had to swap my proportioning valve to get the distribution right. I just used a 96+ (IIRC) and problem was solved.
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Unread 02-11-2013, 09:05 PM   #18
ZJMatt
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Originally Posted by gabrod72 View Post
Shot in the dark here, but did your 95 have drums rear? If so, did your new axle also have drums? Reason I ask is when I swapped my 1993 rear D35 for an 8.8 with disks I had to swap my proportioning valve to get the distribution right. I just used a 96+ (IIRC) and problem was solved.
Both Jeeps were disc front and rear.
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Unread 02-12-2013, 07:18 PM   #19
ZJMatt
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Well, here's a little update. I HAVE BRAKES. Probably have had them all along.

I pulled the master cyl off the parts jeep, and realized it hadn't gone dry. Bench bled it, and swapped mine out with it. Bled the lines again. Same deal. Great pedal when the jeep was off, went to the floor with it running. Pulled the vaccuum line off the booster, pedal was right where it was with the jeep off.

Still stumped, but finally got the balls to try moving it out of the garage (my driveway is a 15% grade straight down to a main road on a blind corner). Inched my way foreward, hit the brakes, and the jeep would stop! Kept building up courage and going a little faster, little further, each time, no matter what the jeep stopped. So I went down to the bottom of the driveway, floored it and got it up to about 15 MPH by the top, hit the brakes, it stopped!

So I have brakes, may have had them all along and just wasn't brave enough to find out.

However, the pedal is still going to the floor! What now?
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Unread 02-12-2013, 08:10 PM   #20
Pugulis
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What year is the parts vehicle?
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Unread 02-12-2013, 08:21 PM   #21
ZJMatt
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Originally Posted by Pugulis View Post
What year is the parts vehicle?
My jeep is a 1995. The parts jeep is a 1998.
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Unread 02-12-2013, 09:31 PM   #22
Pugulis
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I'm not exactly sure what parts you used from the donor vehicle. I did a little research and found that the proportioning valve is the same part number, but the master cylinder is not. Nor is the brake booster. Also how did you reroute the lines from the ABS?
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Unread 02-13-2013, 09:07 AM   #23
ZJMatt
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Originally Posted by Pugulis View Post
I'm not exactly sure what parts you used from the donor vehicle. I did a little research and found that the proportioning valve is the same part number, but the master cylinder is not. Nor is the brake booster. Also how did you reroute the lines from the ABS?
All I used from the parts jeep was the master cyl. It did this with the old master too.

I bypassed the ABS pump by using a T junction off the proportioning valve and running the front lines off that, and connecting the rear lines directly to the proportioning valve.

So the lines go from the master to the valve, then right down to the calipers.
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Unread 02-13-2013, 01:36 PM   #24
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Well, I'm pretty stoked right now. Just took the jeep to the store and back. Got it up to 60, and no death wobble! That was my biggest worry. Like I predicted last night, the brakes do feel a little low, but have no problem stopping or slowing the jeep down. I hardly even noticed going down the road, it was just at low speed and hit them hard I noticed they didn't feel right. Also it seems to pull hard right, when braking.

I'll say already that the jeep goes so much better than before! No howling from the rear end, and it actually seems to have some power now! I do need to adjust the steering box. I can turn the wheels a lot further left than I can right, and the steering wheel is about 180º off. Also it feels really floaty, which I'm guessing is because of the extra lift, blown shock (just got the 2nd one delivered last night) and no sway bars. I plan on installing the new rear shocks and sway next chance I get.
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Unread 02-13-2013, 03:59 PM   #25
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Quote:
Originally Posted by ZJMatt View Post
I bypassed the ABS pump by using a T junction off the proportioning valve and running the front lines off that, and connecting the rear lines directly to the proportioning valve.
This is where your problem is. There should only be one line from the rear (the t junction for it is by the rear axle) and two line from the front. Somehow I think you've connected one front and the rear to the T junction you installed. So the proportioning valve isn't able to do it's job. Basically you have 3 brakes connected to one side and 1 brake to the other. That's probably what's causing the pulling as well.
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Unread 02-13-2013, 04:07 PM   #26
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Originally Posted by Pugulis View Post
This is where your problem is. There should only be one line from the rear (the t junction for it is by the rear axle) and two line from the front. Somehow I think you've connected one front and the rear to the T junction you installed. So the proportioning valve isn't able to do it's job. Basically you have 3 brakes connected to one side and 1 brake to the other. That's probably what's causing the pulling as well.
Nope. Rear is hooked to the valve. Fronts are to the T.
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Unread 02-13-2013, 04:17 PM   #27
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The fronts shouldn't have a T. There should be 3 lines coming directly out of the proportioning valve. One goes to the rear and two go to the front. If it's not like this, you're doing something wrong. There should be no need to use a T for the front.
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Unread 02-13-2013, 04:26 PM   #28
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I've tried explaining this a couple times earlier in the thread. Lead a horse to water...
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Unread 02-13-2013, 04:30 PM   #29
ratmonkey
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the abs pump is already a t off of one front output on the prop valve. that's not his issue. he may have the front and rear brake outputs reversed though.
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Unread 02-13-2013, 05:08 PM   #30
ZJMatt
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Quote:
Originally Posted by Pugulis View Post
The fronts shouldn't have a T. There should be 3 lines coming directly out of the proportioning valve. One goes to the rear and two go to the front. If it's not like this, you're doing something wrong. There should be no need to use a T for the front.
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I've tried explaining this a couple times earlier in the thread. Lead a horse to water...
No, as we went over earlier in the thread, there are 2 different style valves. One has 3 outputs, one has 2. Mine has 2. therefore, I needed the T.

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the abs pump is already a t off of one front output on the prop valve. that's not his issue. he may have the front and rear brake outputs reversed though.
No. Already went over this as well...
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