| From | Message |
Peter
Dodge Dakota
JOIN HERE
2/03/2006
14:38:11
|
 Subject: Spongy, kinda soft brakes
IP: Logged
Message:
I have a 97 CC with a 3.9L, and about 100K miles, rear wheel ABS. I recently changed out the pads and rotors due to the pulsating. I used the Performace Friction Pads (Carbon Metallic) and normal O-Reilly rotors. I noticed my brakes were pretty soft after the change. So I bled the system, and they were still soft so I took it to Pep-Boys. They said the Master Cylinder was bad, so I replaced it with a rebuilt one also from O-Reilly's. Still didn't help, so I replaced the calipers (I thought the boots were binding and holding the piston in) and that didn't help.
I am hearing a noise when I step on the brakes that sounds like a spring creaking and it sounds like it is coming from the brake-booster / master cylinder area.
The first half of the brake travel feels normal but the bottom half feels like I am hauling a boat behind me, and it is real hard to lock them up, even if I try.
When I bled the brakes on the two valves located next to the master cylinder I was loosening the actual brake line fittings as described in the repair manual, but i notice it looks like there are bleed type valves at the ends, should I be using these instead??
Let me know what ya'll think. Sorry so long. Just trying to be thorough.
|
Peter
Dodge Dakota
JOIN HERE
2/03/2006
15:04:37
| RE: Spongy, kinda soft brakes
IP: Logged
Message:
I forgot to mention that pumping the brakes doesn't seem to help.
|
davec
Dodge Dakota
JOIN HERE
2/03/2006
15:11:43
| RE: Spongy, kinda soft brakes
IP: Logged
Message:
I think the first thing I would check is the front brakes you just installed. Make sure they are operating normally and you have everything in its place. (no offense, sh!t happens) Normally when a booster goes bad, you get a hard peddle. I would say master cylinder but you've changed that. Are you getting air out of the system when you bleed it? Does the air go away and come back? Are you bleeding at all 4 wheels?
|
.boB
Dodge Dakota
JOIN HERE
2/03/2006
15:30:30
| RE: Spongy, kinda soft brakes
IP: Logged
Message:
Did you bed the pads EXACTLY as the instructions said to do?
|
Betcha
Dodge Dakota
JOIN HERE
2/03/2006
15:32:37
| RE: Spongy, kinda soft brakes
IP: Logged
Message:
Bad brake booster. Maybe ruined by brake fluid inside. Just had a similar problem with my 98.
|
Peter
Dodge Dakota
JOIN HERE
2/03/2006
17:19:10
| RE: Spongy, kinda soft brakes
IP: Logged
Message:
I have actually had the brakes off several times double checking everything, making sure I didn't miss anything. The pads are set just like the old ones were, so I don't htink that could be it.
However, When I pressed the pistons of calipers in, the brake fluid did overflow. It ran down the master cylinder and brake booster, and it definately could have made it's way in there. It even sat overnight because I didn't finish until the next morning.
Betcha,
Can you explain a little more about what happened with yours?
Thanks for the input guys.
|
Trevor
Dodge Dakota
JOIN HERE
2/03/2006
19:23:01
| RE: Spongy, kinda soft brakes
IP: Logged
Message:
Did you bleed the system properly, from the furthest away brake first?
|
obio3
Dodge Dakota
JOIN HERE
2/03/2006
20:18:02
| RE: Spongy, kinda soft brakes
IP: Logged
Message:
I think you got carried away here with the money spending. Assuming the brakes was working normal other then the pulsing, You needed to figure out what went wrong with your instalation. You have changed so many things at this point you now could have multiple problems. I'm going to go with your original work on the pads/rotors. You said you redone this instalation several times with no change. If that's the case and if things was ok prior to new products being installed, I would be taking a serious look at the new parts. Rotors are pretty basic assuming they are the right part for the aplication. Compare thickness to original ones and total size including design. Next take a real close look at the pads. Compare every demention with originals. Should you not find any differances of any kind and going with the rotors simply being rotors, I would be looking at differant pads made of differant material. I actully believe your going to find your problem is the pads. My reasoning here is what you said. Normal peddle till the pads start to ingage and lots of pressure to get stopped. This can actually give the impression of spungy peddle. Good luck
So many problems .... So little time
|
Peter
Dodge Dakota
JOIN HERE
2/03/2006
21:37:03
| RE: Spongy, kinda soft brakes
IP: Logged
Message:
Trevor, I followed the manual for the bleeding, and it
listed which one to start with and end with.
obio, I know what you mean about buying all of the
parts. When I get so frusterated with a project that
should be simple, I start jumping to easy fixes. I
replaced the master cylinder because pepboys said
they did a leak test on it, and found it to be faulty.
Guess I should have known better. The boots on the
calipers were crimping up quite a bit since I pushed the
pistons back, and I couldn't get them to seat properly. I
didn't even tell you about the hubs I replaced because
they were grinding.
I matched up the rotors with thickness and all, I even
used a little sand paper to get a consistent swirl. The
pads matched up exactly also. Since I got the pads at
autozone I was thinking about taking them back and
getting a normal semi-metallic set. Atleast I'd be able to
make-up a little of the money I lost in all of the other
parts then.
If ya'll can think of anything else, I'm all ears.
|
OBIO3
Dodge Dakota
JOIN HERE
2/04/2006
00:21:57
| RE: Spongy, kinda soft brakes
IP: Logged
Message:
I'm not perfect either but I still think all that's left is the material in the pads. I keep thinging how you dicribed the soft pedle. felt normal till the pads engaged and then spongy. Remember. If you got to push hard on the pads it can feel spungy to the driver. Try getting the truck on a dirt surface. See if all 4 wheel are working correct when you nail the brakes. Might be somehow the ABS isn't working right. Other then that, I'm out of ideas. Good luck
So many problems .... So little time
|
OBIO3
Dodge Dakota
JOIN HERE
2/04/2006
00:26:22
| RE: Spongy, kinda soft brakes
IP: Logged
Message:
One other thought. It could be changing the front brakes threw your rear brakes out of sink meaning the self adjusters may not be working and you only got brakes working on the front wheels.
So many problems .... So little time
|
Dan
Dodge Dakota
JOIN HERE
2/04/2006
01:35:21
| RE: Spongy, kinda soft brakes
IP: Logged
Message:
Go get real help before you run over someone. As a mechanic
pulsating brakes is an easy fix. You guessed on how to bleed the
brakes. now i bet you have air in the line. In the long run now you'll
spend more money getting it done right, than if you paid someone
to do it the first time.
|
stevedak
Dodge Dakota
JOIN HERE
2/04/2006
17:39:52
| RE: Spongy, kinda soft brakes
IP: Logged
Message:
when u get new pads let us know if that fixes ur problem
|
Lewis
Dodge Dakota
JOIN HERE
2/05/2006
00:30:10
| RE: Spongy, kinda soft brakes
IP: Logged
Message:
I had a similar problem after i did my front brakes. Took the stuff apart and put back together more times than i know. Never could figure out why. It was a cool 20degrees outside and i was tired of messing with it. Took it to a shop, had them look at it and flush the brake system as my fluid was brown anyway. It solved the problem, all they could tell me was that they took the caliper off, reseated it. That i didnt have it on/torqued down right, that was causing problems. Make sure youre caliper is seated right and the slide pins are torqued down right, its easy to get them crossthreaded and in croooked.
|
Peter
Dodge Dakota
JOIN HERE
2/06/2006
09:08:53
| RE: Spongy, kinda soft brakes
IP: Logged
Message:
I tried Advance for some new pads but their semi-metallic didn't have the clips like my old ones did, so I got the new ones from AutoZone. I ended up changing out the pads, and so far it feels decent, but I really won't know until I get on it hard. I want to make sure and break in the pads and don't glaze them over or something. I had to use an over-size caliper bolt on the first time, so I decided to put in a heli-coil, just to make sure.
OBIO - I adjusted the rear brakes too, thinking it could be that. I'll try getting it on some dirt, and see if something isn't engaging properly.
Dan-I can understand your comments. My brakes work well enough to pass inspection and stop my truck every time, it just feels like I am hauling a trailer. I made sure to follow the manual exactly with bleeding the brakes. I attempted to take it in and get bled by Pepboys, and they wanted an additional $400 to change out the rear wheel cylinder because they couldn't get the bleed screw loose. When I got it home, it came loose very easily. When I was tightening down the caliper bolts to the specified torque specs, it stripped out the hole. If a shop would have done that, would they have even bothered to tell me or fix it, who knows. If you can't tell, I have a hard time trusting mechanics. If the problem is still there, I do plan on taking it to a different mechanic.
Lewis-Maybe getting rid of that oversize caliper pin will help out if the caliper wasn't seated right.
I'll keep you updated on everything, and thanks for all of the replies.
|
Bob Lincoln
Dodge Dakota
JOIN HERE
2/06/2006
09:15:26
| RE: Spongy, kinda soft brakes
IP: Logged
Message:
You didn't bleed the brakes properly. You said you loosened the lines instead of the bleeder screw. So you still have trapped air. Bleed at the bleeder screws, furthest wheel from the master cylinder first.
|
Peter
Dodge Dakota
JOIN HERE
2/06/2006
09:49:08
| RE: Spongy, kinda soft brakes
IP: Logged
Message:
Bob, At the wheels, I bled the brakes from the bleeder screws. It was just at the valves, and master cylinder that I bled from the lines. The valves (next to the master cylinder) have some sort of nut on end of them, and it looks like you could bleed it from them, but the manual said to bleed from the lines. Let me know if this is what you're talking about. Thanks.
|
Bob Lincoln
Dodge Dakota
JOIN HERE
2/07/2006
08:48:18
| RE: Spongy, kinda soft brakes
IP: Logged
Message:
Do you know how to bleed a master cylinder? You don't loosen the lines and stomp on the pedal. Normally you only bleed a master cylinder when replacing it. To bleed, you connect short, snipped lines to the output connections and coil the open tips back into the open master cylinder, submerge the tips, and gently step on the brake til all bubbles come out. Keep the cylinder filled and the tips immersed at all times. Then disconnect these lines, reconnect the vehicle lines and bleed the four wheels. I'll bet you put air in at the master cylinder.
You don't bleed the proportioning valve on any car I've seen, so I don't know what you did there.
|
Peter
Dodge Dakota
JOIN HERE
2/07/2006
09:08:53
| RE: Spongy, kinda soft brakes
IP: Logged
Message:
I did bench bleed the master cylinder before I put it on. Going by what the Haynes manual said, I also bled the master cylinder at the fittings. If you have a Haynes manual, look at it, and let me know if I shouldn't have done that.
|
Lewis
Dodge Dakota
JOIN HERE
2/11/2006
01:03:01
| RE: Spongy, kinda soft brakes
IP: Logged
Message:
Hmm, I too followed the directions in the Haynes manual. Is it apparently wrong. It definitely says to loosen the lines at the master cylinder to bleed it when bleeding the whole system. Thats probably why it was fixed after they did the complete flush and couldnt really tell me what the actual problem was.
I have seen the Haynes manual be kinda wrong on some other stuff...just nothing that could endanger anyone like the brake system.
|
Peter
Dodge Dakota
JOIN HERE
2/13/2006
08:53:41
| RE: Spongy, kinda soft brakes
IP: Logged
Message:
Lewis, I might end up taking it over to a brake place to have them bleed it all just to make sure.
The new pads seem to have solved the problem. I drive about an hour, every afternoon in traffic, up and down hills. There was once after going down several hills where it was a little softer than normal. Other than that, it feels real good. I am wondering if those carbon metallic pads got glazed over, luckily AutoZone gave me my money back for them.
|
| | P 1 Next Page>> |
