Need Brake help please

[66427]

First...I tried the search function a couple times and could not find an answer, so, as always all help is appreciated.

So I took the Explorer out last week and the brakes seem to be working fine under normal use. Firm pedal, normal stopping distances, no pulsing, pulling, no sponginess or anything out of the ordinary. I was coming up to a redlight where the 1 lane splits to a left turn, straight and a right turn. I was going right as was the driver in front of me. The light turned yellow and he slammed on his brakes. I was already braking and just pushed harder. The pedal went straight to the floor with just a bit more stopping force. Thank god I had a large gap behind him. After the light turns green, brakes are fine. They just will not "Panic stop".

So I am thinking master cylinder...maybe?
There are no leaks and the reservoir is full, could the seals be shot?
Or rubber lines to the calipers ballooning out? Does anyone make braided lines for these?

So, if I change the master cylinder, I know how the bench bleed it, but there will invariably be a small bubble or two introduced into the lines as the swap is performed, is there a simple way to bleed this back to the master cylinder? Or do I have to pump and dump through all 4 calipers?

Again, all hints suggestions and ideas are appreciated.

 

[66427]

First...I tried the search function a couple times and could not find an answer, so, as always all help is appreciated.

So I took the Explorer out last week and the brakes seem to be working fine under normal use. Firm pedal, normal stopping distances, no pulsing, pulling, no sponginess or anything out of the ordinary. I was coming up to a redlight where the 1 lane splits to a left turn, straight and a right turn. I was going right as was the driver in front of me. The light turned yellow and he slammed on his brakes. I was already braking and just pushed harder. The pedal went straight to the floor with just a bit more stopping force. Thank god I had a large gap behind him. After the light turns green, brakes are fine. They just will not "Panic stop".

So I am thinking master cylinder...maybe?
There are no leaks and the reservoir is full, could the seals be shot?
Or rubber lines to the calipers ballooning out? Does anyone make braided lines for these?

So, if I change the master cylinder, I know how the bench bleed it, but there will invariably be a small bubble or two introduced into the lines as the swap is performed, is there a simple way to bleed this back to the master cylinder? Or do I have to pump and dump through all 4 calipers?

Again, all hints suggestions and ideas are appreciated.

FYI...all original except pads and rotors. And Fluid.

 

[swshawaii]

Doubt this will solve your braking issue, but it partially answers your third question. Good luck.

Deerfield Precision Braided SS Brake Lines

These seem to be the only pre made stainless brake lines available for the Gen 2 Explorer. Price and build quality appears comparable to custom made, and DOT approved. Anyone tried or found any benefit with SS? I've read conflicting reviews. TIA Formerly WRXtra Deerfield Precision EDIT 6/3/16...

www.explorerforum.com

 

[C420sailor]

Any ABS codes?

 

[66427]

Any ABS codes?

No.

 

[crunchie_frog]

I have done two master cylinder swaps on these vehicles and I filled up the line/tube that connects up to the master cylinder before I connected it to try to be sure there were not air bubbles. Very little had spilled out anyway, I tried to keep the line/tube as vertical as possible. I did not have any issues. If you do get air in the line/tube they will have to go through the ABS to get to the brakes and getting air out of the ABS is a little more difficult I have read on this forum and may even require a dealer visit.

It sounds like your master cylinder to me. I used the opportunity to do a complete brake fluid flush (through all 4 until clear, starting w/back passenger and so on).

 

[66427]

I have done two master cylinder swaps on these vehicles and I filled up the line/tube that connects up to the master cylinder before I connected it to try to be sure there were not air bubbles. Very little had spilled out anyway, I tried to keep the line/tube as vertical as possible. I did not have any issues. If you do get air in the line/tube they will have to go through the ABS to get to the brakes and getting air out of the ABS is a little more difficult I have read on this forum and may even require a dealer visit.

It sounds like your master cylinder to me. I used the opportunity to do a complete brake fluid flush (through all 4 until clear, starting w/back passenger and so on).

Yes, I did a complete fluid change starting with Pass. Rear to Dr Rear, Pass Front Dr front.

You are confirming my fears that any air introduced during a master cylinder change may require a shop visit if the air goes through the ABS.

 

[crunchie_frog]

Yes, I did a complete fluid change starting with Pass. Rear to Dr Rear, Pass Front Dr front.

You are confirming my fears that any air introduced during a master cylinder change may require a shop visit if the air goes through the ABS.

I would think if I could do it twice, with no problems must not be too difficult. I was just careful to keep the tube vertical, I think I used a rubber band or something to hold it in place while I was banging around in there taking the master cylinder out and then back in.

 

[66427]

I would think if I could do it twice, with no problems must not be too difficult. I was just careful to keep the tube vertical, I think I used a rubber band or something to hold it in place while I was banging around in there taking the master cylinder out and then back in.

I will look when I get home, I thought it was rigid tubing at that point...?

 

[crunchie_frog]

I will look when I get home, I thought it was rigid tubing at that point...?

Yes, it is rigid, it can be moved around though.

 

[jr230]

might try pulling fuse to abs find a safe spot to do the same speed. if it stops ok you have air in abs unit. if does the same problem its in the master cyl. i presume you check caliper's for leaks
i have 99 waiting for clutch and paint, a 03 in junk yard and a 04 ohv 6 cyl previously had 85 ranger s 4cyl carb and 5 sp 0 options all great trucks

 

[Chris_A.]

Yes, I did a complete fluid change starting with Pass. Rear to Dr Rear, Pass Front Dr front.

You are confirming my fears that any air introduced during a master cylinder change may require a shop visit if the air goes through the ABS.

If you bench bleed the master cylinder and are careful, I have not had issues. Remember to break torque on everything before trying to remove it. If the bolts on the brake booster are rusty, treat them before trying to remove.a wire brush is very helpful. These bolts, if rusty, can fail. So, take your time and verify that a brake booster is available (I always replace on my vehicles, yes, I'm a little paranoid about my brakes). Do not loosen the lines at the 4WABS module only at the master cylinder. If you have line wrenches available I highly recommend using them. Regular box wrenches have had me making more. Have some rags underneath to catch the runoff. Check the sensor wire to make sure that the TSB is applied.