Eagle Posted July 2, 2017 Share Posted July 2, 2017 so i'm going from 2 lines running rearward to just 1 and that's coming from the bottom dist port, not the nose correct? Correct. No, NOT correct. As we have documented many times, in many different discussion threads, the lower front outlet on the MJ distribution block/valve is NOT the primary outlet. It is ONLY an emergency bypass circuit, and it sees brake fluid pressure/flow ONLY if the front brake circuit fails. To run a single line to the rear brakes, you connect the "nose" outlet to the rear flex hose. Look again at the photo in post #33 of this thread. Link to comment Share on other sites More sharing options...
Goose_XJ88 Posted July 2, 2017 Share Posted July 2, 2017 Found another thread with a great picture that shows what outlet is what. Looks like Eagle is right and when deleting the load valve you keep the "nose" brake line and plug the outlet pointed to the ground. Now that I think about it, if the lsv always gets brake pressure to determine braking power based on weight in the bed, that is the line you will want to keep and use to give full brake pressure to the rear brakes with the valve deleted. Link to comment Share on other sites More sharing options...
54bobby Posted July 11, 2017 Share Posted July 11, 2017 ok, old lines are out and i have a coil of new line. which way is easiest to get it back in? front to rear or vice-versa and do i bend as i go or pre bend and wrestle it in? any tips or advice would be greatly appreciated. Link to comment Share on other sites More sharing options...
coolwind57 Posted October 5, 2017 Share Posted October 5, 2017 Currently working on other projects for my MJ, but I couldn't resist inspecting my rear brake system. Check out this Load Sensing Valve Delete the PO performed: Load sensing valve body is still installed on the truck though not connected to diff cover. Looks like they just disconnected the old line from it and let it hang in the breeze. Then ran a new solid line from top manifold straight back up front, looping a return back up front. What gets me, is that PO just installed a brand new brake booster with master cylinder like 5-months before I bought the truck. Man, that would had been so cool if he wouild had known about the dual diaphragm upgrade. This guy had owned the truck for a year and complained about lack of good brakes to his local repair shop in town. According to him and a receipt I found, they put on brand new shoes and hardware. He complained that it didn't help, so they installed a brand new booster and master cylinder. No telling when this sensing valve "delete" was performed. I will say that my brakes are adequate...feels like old truck brakes to me. I'll find the time and money to sort this all out and upgrade maybe this Spring if she continues to hold up for me. Link to comment Share on other sites More sharing options...
Eagle Posted October 5, 2017 Share Posted October 5, 2017 7 hours ago, coolwind57 said: Load sensing valve body is still installed on the truck though not connected to diff cover. Looks like they just disconnected the old line from it and let it hang in the breeze. Then ran a new solid line from top manifold straight back up front, looping a return back up front. There is no "return" involved in the MJ braking system. One line is the normal line that runs through the height sensing valve, the other is an emergency circuit that bypasses the height sensing valve if the front brakes fail. If you don't have the load sensing valve hooked up, you should not be running two lines. Link to comment Share on other sites More sharing options...
coolwind57 Posted October 6, 2017 Share Posted October 6, 2017 46 minutes ago, Eagle said: There is no "return" involved in the MJ braking system. One line is the normal line that runs through the height sensing valve, the other is an emergency circuit that bypasses the height sensing valve if the front brakes fail. If you don't have the load sensing valve hooked up, you should not be running two lines. Yep, you're right. My bad, I spoke inaccurately and poorly. What they actually appeared to have done, if I'm correct, is disconnect the sensing valve and plugged in a new metal brake line at the rear T in its place, then using the emergency circuit brake line in reverse to "return" pressure to the proportioning valve. I think that's what's going on. They thought they could just return it back instead of plugging it up or replacing the faulty height sensing valve. Regardless, its a very poor, lazy way that essentially makes a dead loop with potential problems coming sooner or later. I really need to trace and ensure the brake line coming from the HEIGHT SENSOR BRAKELINE orifice (on the diagram provided by Goose XJ88 above) is feeding the soft rear brake hose directly. I can then block off the REAR BRAKELINE orifice on the front proportioning valve and block the rear T where they had installed the new brake line you see in my photo. I will then completely cut out the brake line, REAR BRAKELINE from the truck in its entirety. When I can get to this all, I may just run brand new brake line back there, tearing all the old lines out when I remove the bed this Winter. I'm thinking I will add an adjustable proportioning valve maybe to my dash. If it works that well in real life as it seems on paper, then that would be cool. Link to comment Share on other sites More sharing options...
WyoCherokee Posted October 24, 2017 Share Posted October 24, 2017 Here is a Reference Photo. I spent the Evening tracing lines to make sure i had them correct before performing the operation. Link to comment Share on other sites More sharing options...
coolwind57 Posted October 24, 2017 Share Posted October 24, 2017 53 minutes ago, WyoCherokee said: Here is a Reference Photo. I spent the Evening tracing lines to make sure i had them correct before performing the operation. Awesome. Do you have an "AFTER" photo yet? Link to comment Share on other sites More sharing options...
zomeizter Posted October 24, 2017 Share Posted October 24, 2017 On 10/5/2017 at 10:10 AM, coolwind57 said: Currently working on other projects for my MJ, but I couldn't resist inspecting my rear brake system. Check out this Load Sensing Valve Delete the PO performed: Load sensing valve body is still installed on the truck though not connected to diff cover. Looks like they just disconnected the old line from it and let it hang in the breeze. Then ran a new solid line from top manifold straight back up front, looping a return back up front. What gets me, is that PO just installed a brand new brake booster with master cylinder like 5-months before I bought the truck. Man, that would had been so cool if he wouild had known about the dual diaphragm upgrade. This guy had owned the truck for a year and complained about lack of good brakes to his local repair shop in town. According to him and a receipt I found, they put on brand new shoes and hardware. He complained that it didn't help, so they installed a brand new booster and master cylinder. No telling when this sensing valve "delete" was performed. I will say that my brakes are adequate...feels like old truck brakes to me. I'll find the time and money to sort this all out and upgrade maybe this Spring if she continues to hold up for me. Is that a brass coupler? If so, I'd replace it asap with a steel unit... Link to comment Share on other sites More sharing options...
coolwind57 Posted October 25, 2017 Share Posted October 25, 2017 4 hours ago, zomeizter said: Is that a brass coupler? If so, I'd replace it asap with a steel unit... Looks like it. I'll crawl under there tomorrow and see. Link to comment Share on other sites More sharing options...
HOrnbrod Posted October 25, 2017 Author Share Posted October 25, 2017 There's nothing wrong with brass fittings on brake lines as long as they are flare fittings using double flares, and not compression fittings. Manufacturers have used brass fittings for years on brake lines. Link to comment Share on other sites More sharing options...
Minuit Posted December 3, 2017 Share Posted December 3, 2017 On 6/24/2017 at 8:58 AM, Keyav8r said: If you are considering eliminating your load sensing valve (as I was), do Don's check and adjustment procedure (below) first and see if it improves your braking. I took the arm off mine this morning and found the flat was at about the 4:30 - 5:00 position. After turning the flat to about 7:00 - 7:30 and re-installing the arm, I took my truck out for a test run. Braking action greatly improved from poor to good. The whole job, including getting and putting away tools, jack and stands took about 30.- 45 minutes and was well worth the time. I'm still planning on doing the '96 XJ double diaphragm booster upgrade but the priority has dropped a few spaces down on the to do list. Kudos to Don for this MJ Tech jewel. I adjusted my LSV on the '91 this way last weekend. Mine wasn't as "bad" as Fred's, but turning the flat from 5:30 to about 7:30 noticeably improved braking feel. The pedal feels harder and more responsive, and inspires more confidence overall. I didn't have much time to test, but I suspect I could probably turn the valve a little more before premature rear lockup became a problem. In my tests I was not able to lock the rears with the valve at 7:30, but they are clearly being used. After a drive both drums were hot, and equally so. Like the others I am not going to be deleting my LSV. I would consider this worth testing out for sure. Link to comment Share on other sites More sharing options...
HOrnbrod Posted December 3, 2017 Author Share Posted December 3, 2017 9 hours ago, Minuit said: I adjusted my LSV on the '91 this way last weekend. Mine wasn't as "bad" as Fred's, but turning the flat from 5:30 to about 7:30 noticeably improved braking feel. The pedal feels harder and more responsive, and inspires more confidence overall. I didn't have much time to test, but I suspect I could probably turn the valve a little more before premature rear lockup became a problem. In my tests I was not able to lock the rears with the valve at 7:30, but they are clearly being used. After a drive both drums were hot, and equally so. Like the others I am not going to be deleting my LSV. I would consider this worth testing out for sure. Works even better with disk brakes. Link to comment Share on other sites More sharing options...
Russell E. Gray Posted December 5, 2017 Share Posted December 5, 2017 I'm new here, but from what i'm reading is if the HLV seems to be functional it best to leave it alone. Upon reading the brake bleeding procedure , it's a bit more involved on these MJ's than normal. I've had a local mechanic try to get me good brakes to no avail. I took the bull by the horns & toar it down @ home, & i'm sure after reading this forum w/ all this info, i'll have good brakes. Mossyjaw, N. C. Link to comment Share on other sites More sharing options...
HOrnbrod Posted December 5, 2017 Author Share Posted December 5, 2017 15 hours ago, Russell E. Gray said: I'm new here, but from what i'm reading is if the HLV seems to be functional it best to leave it alone. Upon reading the brake bleeding procedure , it's a bit more involved on these MJ's than normal. I've had a local mechanic try to get me good brakes to no avail. I took the bull by the horns & toar it down @ home, & i'm sure after reading this forum w/ all this info, i'll have good brakes. Mossyjaw, N. C. Welcome aboard. When you get a chance, create a signature for your rig so we all know what you are driving. https://comancheclub.com/forums/topic/51707-cc-members-create-a-signature-to-describe-your-mj/ Link to comment Share on other sites More sharing options...
Goose_XJ88 Posted February 5, 2018 Share Posted February 5, 2018 On 12/2/2017 at 10:54 PM, Minuit said: I adjusted my LSV on the '91 this way last weekend. Mine wasn't as "bad" as Fred's, but turning the flat from 5:30 to about 7:30 noticeably improved braking feel. The pedal feels harder and more responsive, and inspires more confidence overall. I didn't have much time to test, but I suspect I could probably turn the valve a little more before premature rear lockup became a problem. In my tests I was not able to lock the rears with the valve at 7:30, but they are clearly being used. After a drive both drums were hot, and equally so. Like the others I am not going to be deleting my LSV. I would consider this worth testing out for sure. Alright. So I finally got under my stock 92 MJ and adjusted the valve and man what a difference. It isn't amazing by any means but I no longer feel like I need to leave 5 car lengths between the car in front of me. Now I didn't do the whole procedure like is recommended (no jack stands, level ground, or replacing the bushing) but I adjusted the bushing and arm so that it is at the bottom of the 60 degree range of resistance I felt while rotating the LSV. I would now like to see someone do a write up on keeping the LSV with the 95-96 XJ booster and master upgrade. Link to comment Share on other sites More sharing options...
HOrnbrod Posted February 5, 2018 Author Share Posted February 5, 2018 12 minutes ago, Goose_XJ88 said: I would now like to see someone do a write up on keeping the LSV with the 95-96 XJ booster and master upgrade. I do have the 95 XJ master/booster and Ford Explorer rear disk brakes. With the LSV. Why do you need a writeup?? Link to comment Share on other sites More sharing options...
Eagle Posted February 5, 2018 Share Posted February 5, 2018 I agree with Hornbrod. Why do you need a write-up to NOT remove something? Link to comment Share on other sites More sharing options...
Goose_XJ88 Posted February 5, 2018 Share Posted February 5, 2018 I guess I haven't really looked at the brake line layout or paid attention to what lines go where.. Assuming I keep the MJ distribution block, there are 2 lines that go to the MJ Master and those 2 lines go to 95/96 XJ master? Like I said, I have not looked too deep into this or what the stock layout is.. Link to comment Share on other sites More sharing options...
Eagle Posted February 6, 2018 Share Posted February 6, 2018 3 hours ago, Goose_XJ88 said: I guess I haven't really looked at the brake line layout or paid attention to what lines go where.. Assuming I keep the MJ distribution block, there are 2 lines that go to the MJ Master and those 2 lines go to 95/96 XJ master? Correct. To retain the LSV, you have to keep the MJ distribution block. The inputs (the top side) are identical between the XJ and the MJ, so you run the lines from the 95 master to the MJ distribution block exactly the same way they ran to the XJ proportioning valve. Link to comment Share on other sites More sharing options...
HOrnbrod Posted February 6, 2018 Author Share Posted February 6, 2018 For your 92MJ, the 95/96 booster master is pure bolt-in. The only fab you have to do are the two brake lines from your existing distribution block to the new master cylinder. Buy a 2' length for pre-flared 3/16" brake line from AZ or similar, use the two existing flares on the distribution block, bend and flare the other ends for the master, and bolt it in. Easy-peasy and an excellent brake upgrade. Link to comment Share on other sites More sharing options...
WyoCherokee Posted February 12, 2018 Share Posted February 12, 2018 Some supplemental photos This pic, if you are switching to a ZJ or XJ Distribution block, and coupling the lines together at the "t" fitting. Link to comment Share on other sites More sharing options...
WyoCherokee Posted February 12, 2018 Share Posted February 12, 2018 this photo if you are keeping the MJ distribution block, plugging the lower front port and using the "snout line." I mocked up the rear hose on the line you would hook it to( the black rubber line. Napa Part #38624) This hooks top the 7/16's fitting that would have been plummed in to the side of the load sensing valve. Link to comment Share on other sites More sharing options...
Bsracing Posted August 28, 2018 Share Posted August 28, 2018 So we are going lone #2 to #5 and getting rid of the T fitting. So basically we are using the bypass line to run the rear brakes. Am I gathering this all correctly? Link to comment Share on other sites More sharing options...
Eagle Posted August 29, 2018 Share Posted August 29, 2018 11 hours ago, Bsracing said: So we are going lone #2 to #5 and getting rid of the T fitting. So basically we are using the bypass line to run the rear brakes. Am I gathering this all correctly? I don't have any idea what #2 and #5 refer to, but you do NOT use the bypass line to run the rear brakes, because it's a bypass line that only functions when the front brakes have completely failed. Are you keeping the MJ front distribution block, or replacing it with one out of a ZJ, XJ, or YJ? That makes a difference. Link to comment Share on other sites More sharing options...
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