Bleed Brake Master Cylinder On Vehicle & Related

[J_C]

The brakes on my '98 seemed fine. Firm pedal, good stopping power. Had a front right hose go out, suddenly no brakes. Fortunately no collision.

I thought these were dual chamber master cylinders so loss of front, should've kept rear brakes working? Seems like the same thing happened a few years back, at the time lost a rear hard line (across the axle) and had almost no front brakes too.

If the brakes weren't firm before this fault, I'd have been thinking the master cylinder was on the way out. I expect that the master cylinder has air in it. I may or may not replace the MC but if I don't, has anyone had any problems doing a bench bleed on the vehicle, like with one of those Dorman universal kits #13911 ?

Has anyone removed the reservoir from one of these MC (in recent years so they're about as old) and had any problem with them disintegrating from age, brittleness?

The vehicle has not been started since last parked. Is there any advantage to unplugging the ABS module or pulling the fuse, so it doesn't energize the next time the vehicle is started? I accept that I might have to bleed ABS too, but of course would be even better if there's no air in it (yet).

Looks like I already had bought a new front right brake hose, but it didn't come with a bracket or clip. Anyone sourced those locally if mine is disintegrated, maybe Advance Auto or Autozone? If it holds the job up, I can fabricate a bracket but the clip itself... guess I could hack something out for that as well but I know the auto parts stores sell some clips, just not sure if they fit.

 

[Pete Deering]

The brakes on my '98 seemed fine. Firm pedal, good stopping power. Had a front right hose go out, suddenly no brakes. Fortunately no collision.

I thought these were dual chamber master cylinders so loss of front, should've kept rear brakes working? Seems like the same thing happened a few years back, at the time lost a rear hard line (across the axle) and had almost no front brakes too.

If the brakes weren't firm before this fault, I'd have been thinking the master cylinder was on the way out. I expect that the master cylinder has air in it. I may or may not replace the MC but if I don't, has anyone had any problems doing a bench bleed on the vehicle, like with one of those Dorman universal kits #13911 ?

Has anyone removed the reservoir from one of these MC (in recent years so they're about as old) and had any problem with them disintegrating from age, brittleness?

The vehicle has not been started since last parked. Is there any advantage to unplugging the ABS module or pulling the fuse, so it doesn't energize the next time the vehicle is started? I accept that I might have to bleed ABS too, but of course would be even better if there's no air in it (yet).

Looks like I already had bought a new front right brake hose, but it didn't come with a bracket or clip. Anyone sourced those locally if mine is disintegrated, maybe Advance Auto or Autozone? If it holds the job up, I can fabricate a bracket but the clip itself... guess I could hack something out for that as well but I know the auto parts stores sell some clips, just not sure if they fit.

1. Explorer have dual circuit brake system.
The rear circuit (secondary circuit) must have been bad for a long time. That why you did not notice it. I lose my rear line while pulling a trailer going a hill and was coming to a stop. My brake petal hit the floor,but came back up and the car stop fine with the front primary brake circuit. Are car have 4 wheel disc. It not like front disc and rear drums system( more noticeable).

2.I have bench bleed, a master cylinders. I also buy 2- 12 inch long brake line tubing. Mount the MC in a bench vise, install the brake line in each port and bend the tube up and over into the MC reservoir. And use the back side of my ratchet hand , which is round to pump the piston in the MC. Easy way to get the air out.
With everything in still in place, I install the MC on the car.

3. I replaced all my hard lines and I did not have a issue bleeding the brakes. I used a vacuum bleeder and also I have speeder installed all around. It makes it easy for one person bleeding.

 

[donalds]

^^^ Only thing I can add is don't push The piston in to far when you're bleeding
Mess up a seal

 

[J_C]

1. We have dual circuit brake system.
The rear circuit (secondary circuit) must have been bad for a long time. That why you did not notice it. I lose my rear line while pulling a trailer going a hill and was coming to a stop. My brake petal hit the floor,but came back up and the car stop fine with the front primary brake circuit. Are car have 4 wheel disc. It not like front disc and rear drums system( more noticeable).

I am doubting the rear was already bad for two reasons.

1) It was the rear I worked on previously, and it has no leaks since then. I'd even replaced front pads 2-3K mi. ago and had checked fluid level then.

2) When the rear hard line failed, it was the same situation, loss of front braking (only a very tiny amount of braking with pedal dropping to the floor) despite there being no leaks in the front. Fluid level remained full for a few years, though not a lot of miles. I'd been checking the fluid periodically, had stayed full till the sudden ruptures.

This is what puzzles me, that both of these failures, to not have braking from the other axle(s) when one fails, do not jive with what should happen from a dual chamber setup. It's acting like it's a single chamber design which makes me wonder if there's some odd wear pattern where an o-ring between the two chambers would wear more than the rest. Seems odd to suspect that, yet, it seems odd to have a dual chamber MC not acting like one. Until I laid my hands on it (lol) it was all factory, besides rotor and pad changes, normal derusting and lubing associated with, not a modified brake system.

2.I have bench bleed master cylinders. I also buy 2- 12 inch long brake line tubing. Mount the MC in a bench vise, install the brake line in each port and bend the tube up and over into the MC reservoir. And use the back side of my ratchet hand , which is round to pump the piston in the MC. Easy way to get the air out.
With everything in still in place, I install the MC on the car.
3. I replaced all my hard lines and I did not have a issue bleeding the brakes. I used a vacuum bleeder and also have speeder installed all around. The make easy for one person bleeding.

I suppose my concern is more about, since I'm possibly not replacing the master cylinder, if it is level on the firewall (including while I have the right front wheel jacked up) enough to bleed in that position rather than removing it. However the last time when I had the rear line fail, it seemed like surely there would be air in the master cylinder then too, yet through normal bleeding (twice, then once after getting some ABS activations going to see if any air would come out of the ABS module) the pedal returned to full firmness.

 

[J_C]

Decided to replace the caliper while I'm at it. Cardone reman coated semi-loaded calipers are annoying.

Mine had extra thick globs of coating on the bracket where it mounts on the knuckle, had to be filed down, then I grease up the slider rails, put shims on, grease those up, and find out the coating is also too thick on the slider rails so not enough room for the brake pad ears... on low mileage pads, not a lot of rust on them yet.

Had to take shims out, clean out grease, and file down the coating, and slightly chamfer the brake pad ears to get them in. Then go to mount them, and find that Cardone has put the coating in the tapped holes for the knuckle bolts too, so can't start threading the mounting bolts... take back off, chase the threads, repeat.

On the 2C215 eHCU aka ABS hydraulic module, which port (#2 or #3) is left and which is right front wheel? Checked the workshop manual but they aren't labeled.

 

[C420sailor]

Don’t mess with the ABS unless you have an issue. 95% of the time, air doesn’t get into the pump

 

[J_C]

First I had a hose job, but the hard line nut was rusted badly, started twisting the hard line so I'm just going to replace it too, so it's coming off the ABS module.

Gotta luv cities where they salt the roads in winter even if there isn't much chance of snow and ice!

If nobody knows then I'll just trace the shorter run to the left front wheel and through process of elimination, know the other port (#2 vs #3) is the right front.

 

[410Fortune]

1 is front brake Feed from master 2 and 3 go to front calipers

4 is rear brake feed from master 5 is out to rear axle calipers

I dislike the 4wabs pumps I like to delete them the abs brake systems that pulse the pedal are
My arch enemy

 

[J_C]

^ Thanks. I realize that... the question is which front wheel caliper #2 goes to, and which front wheel caliper #3 goes to.

I'd already know by now but got caught up doing something else.

I'll probably delete my ABS pump when it fails. What's the best option T-fitting/coupler to get the one feed from the front MC output to both front wheels? Just any of them, in brass?

 

[429CJ-3X2]

Pulling the fuse worked for me when my ABS wasn't working correctly.

 

[J_C]

^ Which fuse? When I pulled a fuse on my '98 to disable ABS, speedo stopped working and it generated a trouble code.

This was a few years back so I'm not 100% certain but think the fuse was interior fuse panel #14 "4 Wheel Anti-Lock Brake System Module, 4WABS Main Relay"

 

[429CJ-3X2]

The fuse I pulled was in the Battery Junction Box under the hood. This was in my 2002 Sport Trac, so your Explorer may be slightly different. On my truck, it was F1.28, which is a 30 amp fuse.

 

[410Fortune]

Yes I use a tee
Block to split the front mc output to the calipers
I also re flare the factory brake lines,
Makes life easier