Contour Enthusiasts Group Archives Forums Modifications Brakes Spungy pedal

03/98 Mytique LE V6 disc/drum:I had to replace a wheel bearing, replaced the front pads, turned the rotors (in spec.), replaced front struts/springs. Road test reveals spungy pedal. Did CTG search found only the "wrongly installed caliper spring" deal. Springs look OK, bearing on the caliper bracket at two flats, though I can't find a photo to double check. When the car was on jackstands (wheels off, key off) it has a pedal. Wheels back on and started it has no/spungy pedal?
Any idea's?


Sav

You didn't just walk in and post right? I mean, you pumped it a few times right? Maybe you need to bleed the brakes.

No, its been a couple days lookin this over, but I would like to get my car back soon.
Since the brakes worked fine previously and I didn't open the system, I'm thinking it doesn't have air in it. But who know's?
I'm leaning toward the master finaly giving way after a backflow of crap.
The brakes seam to work with the wheels off. I wonder if this is because the rotors shift angulary on the hub(more travel or gets the piston out of a dead spot?). Maybe I should clean a regrease the pins and slides?
The design of the caliper doesn't put the center of the piston over the center of the pad. Would seam to cause cocking of the caliper and uneven wear, but have always had even wear.

Sav

To start with, until the new pads seat into the rotors you will have a slightly soft pedal. I don't know just how soft of a pedal you are talking about so I'm not saying that this is definitely your cause.

For future reference, it is a good idea to not force brake fluid backward in the system. When you compress the pistons it is best to open the caliper bleed ports and allow the fluid from compressing the piston back into the caliper to escape to the outside.

Whenever you replace brake pads it is critical that you properly lubricate the caliper slide pins and make sure that they move freely. It is also important to lubricate the pad backing plate anywhere it touches the caliper.

So at this point, if you have just a slightly softer pedal and the brakes are other wise safe, drive the car for a week or so and see if the pedal improves as the pads seat in. If you think it is more than that, take things back apart and make sure they are properly lubricated and that the retainer clips are properly installed. Next, bleed or flush the brake system. Usually if there is damage to the master cylinder from backwash, the master will fail completely, not just slightly, so I don't think it is likely that changing the master will help.

Thanks for the replies! I will be taking the brakes apart, cleaning and lubing the slide surfaces. I will also try bleading.
The odd thing is the pedal is hard as a rock with the wheels off. This makes me question air in the system.

Sav

When you say the pedal is hard as a rock with the wheels off, do you also have the engine turned off? If so, that will affect the feel of the pedal, since you aren't generating brake booster vacuum.

I second Big Jim's comments about the brake pads seating to the rotors. I just went through that a couple of months ago. After I replaced the front pads and rotors, it took a few weeks, and a few thousand miles, before I finally got "good" brakes.

Went through and did the brakes right this time, removed the calipers from brackets, cleaned and lubed, blead system. In the end it was the caliper spring intalled wrong thing. I just couldn't see any other way than how I installed it. Chiltons illustation was no help. I now have the spring installed so the bow is under the bracket instead of in between the bracket and caliper. Thanks for helping out this stress case.
Sav

If someone had a picture of how the spring clip is supposed to be in there, it should be stickied at the top of this forum. It would be a useful reference.

that sticky is gonna be pretty much useless. trust me, people can look at the assembled side and compare it to the side they work with (how 1st brake job should be done ALWAYS!) and see no difference. happened to the best of us

it's funny really, because if you stop to think about why the spring is in there and what is its purpose, you will immediately see how it should go in. of course it takes a testdrive to start thinking

OK, I'll bite: why is it there?