Jeep Cherokee Forum
I'm replacing the brake booster and master cylinder with a larger one from a '95 XJ (I think...I pulled it from the junk yard 2 years ago and don't remember...). I wanted to disconnect the hardlines from the proportioning valve, but couldn't really get at the back one. Got the front one loose, then decided to just take them off the master cylinder first.
I'm replacing the brake booster and master cylinder with a larger one from a '95 XJ (I think...I pulled it from the junk yard 2 years ago and don't remember...). I wanted to disconnect the hardlines from the proportioning valve, but couldn't really get at the back one. Got the front one loose, then decided to just take them off the master cylinder first.
0 2016/07/12 21:23:49
Move your windshield washer fluid tank out of the way.
Move your windshield washer fluid tank out of the way.
0 2016/07/12 21:25:35
Any idea what these two connect to? They're on the same harness as the connector that is on the proportioning valve, but they were just sitting under the brake booster.
Any idea what these two connect to? They're on the same harness as the connector that is on the proportioning valve, but they were just sitting under the brake booster.
0 2016/07/12 21:26:22
Driver's side, front brake hard line to rubber line fitting got chewed up when I was replacing the rubber line. Let's fix it.
Driver's side, front brake hard line to rubber line fitting got chewed up when I was replacing the rubber line. Let's fix it.
0 2016/07/17 22:48:39
I took this after the fact, but but off the old flare, as close to the flare as you can. Try to save as much of the hard line as possible.
I took this after the fact, but but off the old flare, as close to the flare as you can. Try to save as much of the hard line as possible.
0 2016/07/17 22:49:30
Since that final bend is right near the end of the line, it's tough to straighten. You need to straighten it so you can get the new fitting on far enough to leave room for the flaring tool.
Since that final bend is right near the end of the line, it's tough to straighten. You need to straighten it so you can get the new fitting on far enough to leave room for the flaring tool.
0 2016/07/17 22:50:09
Find some scrap lumber, drill a 3/16" hole in it and carefully shove the line through the hole. You can straighten your line this way.
Find some scrap lumber, drill a 3/16" hole in it and carefully shove the line through the hole. You can straighten your line this way.
0 2016/07/17 22:51:09
Put the new fitting on.
Put the new fitting on.
0 2016/07/17 22:52:06
Flare the tube, then bend the hard line back so it will mate with the rubber one.
Flare the tube, then bend the hard line back so it will mate with the rubber one.
0 2016/07/17 22:52:32
And here's where the fun begins. There are 4 types of tubing flares out there: 45-degree single and double flares, 37-degree single flare, and a bubble or metric flare. 37-degree is used with stainless steel lines where AN (army-navy) fittings are required (high performance). 45-degree single flares are used with lower pressure applications (carb lines, etc). The two common flares on brakes are the 45-deg double (on the left in the picture) and the bubble or Metric style (on the right in pic)
And here's where the fun begins. There are 4 types of tubing flares out there: 45-degree single and double flares, 37-degree single flare, and a bubble or metric flare. 37-degree is used with stainless steel lines where AN (army-navy) fittings are required (high performance). 45-degree single flares are used with lower pressure applications (carb lines, etc). The two common flares on brakes are the 45-deg double (on the left in the picture) and the bubble or Metric style (on the right in pic)
0 2016/07/17 22:53:02
The 1/2" wrench will fit over the upper fitting and allow you to break it loose. Be sure to secure the proportioning valve by using a 19mm wrench like the one in my left hand.
The 1/2" wrench will fit over the upper fitting and allow you to break it loose. Be sure to secure the proportioning valve by using a 19mm wrench like the one in my left hand.
0 2016/07/17 22:58:40
These are the two fittings needed for the proportioning valve. Note, for the 45-deg double flare, you need to get fittings labeled "Inverted Thread Size"
These are the two fittings needed for the proportioning valve. Note, for the 45-deg double flare, you need to get fittings labeled "Inverted Thread Size"
0 2016/07/17 22:58:46
So the purple connector is an M12-1.0 which goes to the '95 Cherokee master cylinder, as does the M10-1.5 on the top hard line. The top hard line is 30" long and has bubble flares on both ends. I'm cutting this one in half and using the two bubble flares as the Master Cylinder sides of my two new lines.
So the purple connector is an M12-1.0 which goes to the '95 Cherokee master cylinder, as does the M10-1.5 on the top hard line. The top hard line is 30" long and has bubble flares on both ends. I'm cutting this one in half and using the two bubble flares as the Master Cylinder sides of my two new lines.
0 2016/07/17 22:58:52
Rounded off the nuts on the hard lines where they mate to the rubber lines.
Rounded off the nuts on the hard lines where they mate to the rubber lines.
0 2016/07/19 10:28:54
Some of these pics are after the fact. Push the nut up out of the way and cut the hard line just above the flare.
Some of these pics are after the fact. Push the nut up out of the way and cut the hard line just above the flare.
0 2016/07/19 10:31:01
Straighten the tube so you can get the new nut far enough up the line to attach the flaring tool. The final bend was too close to the end of the tube for my bender, so I drilled a 3/16" hole in some scrap lumber and fed the tube through until I got it straight.
Straighten the tube so you can get the new nut far enough up the line to attach the flaring tool. The final bend was too close to the end of the tube for my bender, so I drilled a 3/16" hole in some scrap lumber and fed the tube through until I got it straight.
0 2016/07/19 10:31:50
0 2016/07/19 10:33:02
New nut.
New nut.
0 2016/07/19 10:33:08
Flare it, then add the bend back. Make sure it sits where it can mate with the rubber line.
Flare it, then add the bend back. Make sure it sits where it can mate with the rubber line.
0 2016/07/19 10:33:19
45deg double flare on the left and a bubble or metric flare on the right. The original master cylinder used the left flare, while the new one from the 95 XJ uses the bubble flare on the right.
45deg double flare on the left and a bubble or metric flare on the right. The original master cylinder used the left flare, while the new one from the 95 XJ uses the bubble flare on the right.
0 2016/07/19 10:33:55
How I broke the back fitting loose. A 1/2" wrench will fit over the nut and down the tubing. Holding the proportioning valve is a 19mm wrench.
How I broke the back fitting loose. A 1/2" wrench will fit over the nut and down the tubing. Holding the proportioning valve is a 19mm wrench.
0 2016/07/19 10:35:59
These are the nuts used on the proportioning valve. Be sure to get "Inverted Thread" nuts.
These are the nuts used on the proportioning valve. Be sure to get "Inverted Thread" nuts.
0 2016/07/19 10:36:46
The master cylinder uses an M12-1.0 and an M10-1.5 nut. I had to buy hard lines to get the new nuts. The 30" line in back has bubble flares on both ends, so I cut it in half and used those as my new hard lines to the prop valve with the bubble flares on the master cylinder side.
The master cylinder uses an M12-1.0 and an M10-1.5 nut. I had to buy hard lines to get the new nuts. The 30" line in back has bubble flares on both ends, so I cut it in half and used those as my new hard lines to the prop valve with the bubble flares on the master cylinder side.
0 2016/07/19 10:36:52
Rounded the nut on the driver's side hard line.
Rounded the nut on the driver's side hard line.
0 2016/07/19 22:45:30
Push the nut up and cut the tubing as close to the flare as possible.
Push the nut up and cut the tubing as close to the flare as possible.
0 2016/07/19 22:45:58
That final bend is too close to the end of the line for me to straighten so I drilled a 3/16" hole in a piece of scrap lumber and forced the tube through, straightening it. I needed it straight so I could get the new nut high enough to fit the flaring tool on.
That final bend is too close to the end of the line for me to straighten so I drilled a 3/16" hole in a piece of scrap lumber and forced the tube through, straightening it. I needed it straight so I could get the new nut high enough to fit the flaring tool on.
0 2016/07/19 22:46:25
0 2016/07/19 22:47:40
Put the new nut on.
Put the new nut on.
0 2016/07/19 22:47:48
Flare and bend. Connect the new soft line and attach it to the inner fender wall.
Flare and bend. Connect the new soft line and attach it to the inner fender wall.
0 2016/07/19 22:48:04
Old MC fittings were the standard 45deg double flare on the left. The new MC from the '95 uses the metric or 'bubble' flare....wankers.
Old MC fittings were the standard 45deg double flare on the left. The new MC from the '95 uses the metric or 'bubble' flare....wankers.
0 2016/07/19 22:48:54
Brake that rear nut loose. The 1/2" wrench will slip over the hard line and get down there. Be sure to hold the prop valve (19mm wrench)
Brake that rear nut loose. The 1/2" wrench will slip over the hard line and get down there. Be sure to hold the prop valve (19mm wrench)
0 2016/07/19 22:49:57
These are the nuts that fit the prop valve. Be sure to buy the "inverted thread" type for the double 45deg flare.
These are the nuts that fit the prop valve. Be sure to buy the "inverted thread" type for the double 45deg flare.
0 2016/07/19 22:50:05
The MC requires an M12-1.0 (purple connector) and an M10-1.5 (green connector). The top hard line is 30" long with bubble flares on both ends. Since I need two lengths of line with bubble flare on the MC end and a double 45deg flare on the other, I just cut it in half and used those.
The MC requires an M12-1.0 (purple connector) and an M10-1.5 (green connector). The top hard line is 30" long with bubble flares on both ends. Since I need two lengths of line with bubble flare on the MC end and a double 45deg flare on the other, I just cut it in half and used those.
0 2016/07/19 22:50:20
Bent the old lines up and bench bled the new setup. Kept pumping until the fluid was clean.
Bent the old lines up and bench bled the new setup. Kept pumping until the fluid was clean.
0 2016/07/19 22:50:30
0 2016/07/19 22:50:38
Tilt it upright, remove connectors and tape up the orifices so they won't leak as you install the MC
Tilt it upright, remove connectors and tape up the orifices so they won't leak as you install the MC
0 2016/07/19 22:50:45
New hard lines mounted. I put a bit of power steering hose around the back line as it makes contact with the booster. That should keep it from wearing.
New hard lines mounted. I put a bit of power steering hose around the back line as it makes contact with the booster. That should keep it from wearing.
0 2016/07/19 22:50:51
Install the new booster/MC
Install the new booster/MC
0 2016/07/19 22:51:00
Connect the lines. I had almost no fluid leak.
Connect the lines. I had almost no fluid leak.
0 2016/07/19 22:51:06
Those two connectors from my previous post drive those two washer fluid pumps, I think.
Those two connectors from my previous post drive those two washer fluid pumps, I think.
0 2016/07/19 22:51:13