A-man930 Posted November 22, 2009 Share Posted November 22, 2009 After realizing the rather large amount of confusion surrounding our trucks' braking systems, I've decided to hold off on my own endeavor untill I have a few issues clarified. 1. The junction block up by the master cylinder... does it preform any proportioning functions? or is it basically a glorified Tee connection with a fancy safety feature? (the extra line going to the rear that supposedly bypasses the rear height valve in the case of front brake failure) 2. If this thing isn't any more than a junction, is there any reason I can't just replace the thing with some Tee junctions? I was planing one Tee to divert direct MC pressure to the two front calipers, and then plumbing an adjustable prop. valve into the rear line prior to diverting it to the wheel cylinders on each side. Am I missing anything here?? Link to comment Share on other sites More sharing options...
cmelo Posted November 22, 2009 Share Posted November 22, 2009 Why not just use a XJ proportioning valve? Heck of alot easier than doing what you're talking about. :dunno: Link to comment Share on other sites More sharing options...
CWLONGSHOT Posted November 22, 2009 Share Posted November 22, 2009 Why not just use a XJ proportioning valve? Heck of alot easier than doing what you're talking about. :dunno: I agree..... OR trash the whole shebang and upgrade to a WJ setup for FAR better braking all around.!! :bowdown: CW Link to comment Share on other sites More sharing options...
Eagle Posted November 22, 2009 Share Posted November 22, 2009 1. The junction block up by the master cylinder... does it preform any proportioning functions? No. (the extra line going to the rear that supposedly bypasses the rear height valve in the case of front brake failure) There is no "supposedly" about it. That is what the second line does. 2. If this thing isn't any more than a junction, is there any reason I can't just replace the thing with some Tee junctions? I was planing one Tee to divert direct MC pressure to the two front calipers, and then plumbing an adjustable prop. valve into the rear line prior to diverting it to the wheel cylinders on each side. Am I missing anything here?? What you're missing is that the front junction block also has the slider switch that controls the brake system failure warning light. I don't know for certain, but I suspect it's probably against both Federal and state law to remove or disable that. Why do you think you need to replace it with tees to use an adjustable proportioning valve? Leave the OEM distribution block in place. Plug the outlet for the rear bypass line, and put your adjustable valve in the one line you run to the back. Done. Link to comment Share on other sites More sharing options...
HOrnbrod Posted November 22, 2009 Share Posted November 22, 2009 I agree..... OR trash the whole shebang and upgrade to a WJ setup for FAR better braking all around.!! :bowdown: CW Not to steal this thread, but has anyone here done the WJ brake conversion on an XJ/MJ? Link to comment Share on other sites More sharing options...
CWLONGSHOT Posted November 22, 2009 Share Posted November 22, 2009 I have read a couple nice writeups. Omix-ada makes a complete kit with all required parts!! I have about half the parts in the garage... next summer it will likely become a reality for my MJ!!! Watch for the write up!!! :brows: :brows: CW Link to comment Share on other sites More sharing options...
HOrnbrod Posted November 22, 2009 Share Posted November 22, 2009 I have read a couple nice writeups. Omix-ada makes a complete kit with all required parts!! I have about half the parts in the garage... next summer it will likely become a reality for my MJ!!! Watch for the write up!!! :brows: :brows: CW Know of a link to that kit CW? :brows: Link to comment Share on other sites More sharing options...
LoTGoD Posted November 22, 2009 Share Posted November 22, 2009 Not to steal this thread, but has anyone here done the WJ brake conversion on an XJ/MJ?My WJ MC and booster are in place, but not road tested yet. No WJ proportioning valve in mine, just the stock MJ with the rear bypass blocked off. Link to comment Share on other sites More sharing options...
HOrnbrod Posted November 22, 2009 Share Posted November 22, 2009 Sorry, I should have been clearer. I mean the WJ front disk brakes; rotors, calipers, pads, and new hubs. Link to comment Share on other sites More sharing options...
CWLONGSHOT Posted November 23, 2009 Share Posted November 23, 2009 The write-ups I am talking about only utilize the booster, MC and prop valve. Basically three things need to be overcome. 1) convert lines from "bubble" to double flair. 2) reshape the op-rod on the booster 3) install a 1/4" spacer as the op-rod is a 1/4" too long. The WJ uses a 5on5 bolt pattern, the steering linkages are also different. Swapping in the whole front suspension and brakes is doable, but would be a large undertaking. CW Link to comment Share on other sites More sharing options...
HOrnbrod Posted November 23, 2009 Share Posted November 23, 2009 The write-ups I am talking about only utilize the booster, MC and prop valve.CW Did all that a couple of years ago CW. :D There was a writeup I read somewhere (maybe NAXJA) of a front disk brake upgrade using WJ (or maybe ZJ, or even late model XJ) calipers, rotors, hubs, etc. and keeping the 5x4.5 bolt pattern. Now that I think more about it, must have been the late model XJ or ZJ. You keep the same axle and replace the hub on out to the later model brake parts. I'll have to dig for it I guess.......... Link to comment Share on other sites More sharing options...
Eagle Posted November 23, 2009 Share Posted November 23, 2009 Did all that a couple of years ago CW. :D There was a writeup I read somewhere (maybe NAXJA) of a front disk brake upgrade using WJ (or maybe ZJ, or even late model XJ) calipers, rotors, hubs, etc. and keeping the 5x4.5 bolt pattern. Now that I think more about it, must have been the late model XJ or ZJ. You keep the same axle and replace the hub on out to the later model brake parts. I'll have to dig for it I guess.......... I think it was a few years ago, in Jp Magazine. I haven't had a subscription to that rag for a couple or thre years, but I'm pretty sure that's where I saw it, so it would have been at least that far back. There would be no "upgrade" to using ZJ brakes and hubs -- they are the same as XJ. In fact, the ZJ ceased to exist before Jeep went back to one-piece rotors on the XJ, so arguably rotors from a 2000 or 2001 XJ would be an upgrade for any ZJ, not the other way 'round. Link to comment Share on other sites More sharing options...
HOrnbrod Posted November 23, 2009 Share Posted November 23, 2009 Yeah, it's probably upgrading to the 1994 and up rotors and hubs after they were standardized for both 2WD and 4WD. My problem on the 91 is the 2WD caliper brackets have worn down where the caliper rides the the bracket surface causing vibration (squeal) from the caliper. Lubrication w. caliper grease helps for a very short time. And of course, new 2WD caliper brackets are no longer available anywhere. I pulled the worst one on the right and had a shop weld a wire bead across the upper and lower caliper mounting surfaces, then grinded it down smooth, and it really helped, but this is just a stop gap measure. :fs1: Link to comment Share on other sites More sharing options...
A-man930 Posted November 23, 2009 Author Share Posted November 23, 2009 There is no "supposedly" about it. That is what the second line does. The supposedly is in refrence to the cutaways I've seen on here that don't have the port drilled completely through... What you're missing is that the front junction block also has the slider switch that controls the brake system failure warning light. I don't know for certain, but I suspect it's probably against both Federal and state law to remove or disable that.. Point taken. Why do you think you need to replace it with tees to use an adjustable proportioning valve? Leave the OEM distribution block in place. Plug the outlet for the rear bypass line, and put your adjustable valve in the one line you run to the back. Done. I guess the only reason I was toying with that idea is due to my worries/concers after seeing those nasty cutaways... what else is wrong with this thing??? Thanks for the imput BTW :D Link to comment Share on other sites More sharing options...
Eagle Posted November 23, 2009 Share Posted November 23, 2009 The cutaway was mine. Since the bypass port (the one that wasn't drilled all the way through on the one I cut open) is the one you block when eliminating the rear height-sensing valve, it doesn't make any difference if that port is drilled all the way through or not. Don't make extra work for yourself. Link to comment Share on other sites More sharing options...
Pete M Posted November 23, 2009 Share Posted November 23, 2009 Link to comment Share on other sites More sharing options...
A-man930 Posted November 24, 2009 Author Share Posted November 24, 2009 The cutaway was mine. Since the bypass port (the one that wasn't drilled all the way through on the one I cut open) is the one you block when eliminating the rear height-sensing valve, it doesn't make any difference if that port is drilled all the way through or not. Don't make extra work for yourself. I understand. So that leaves the warning switch as the only reason not to just use a tee (I'll check on the legality of that here in Missouri.) The extra work isn't really a concern as I was planning on cleaning up the whole mess of brake lines I've created with the '96 booster/MC swap I did over the summer. My main concern revolved around wether there was any metering done by that block. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now