Partial brake failure troubleshoot..... [Archive] - GrandAmGT.com Forum

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sugar ray
03-25-2013, 01:40 AM
Ok here is the scoop. We purchased a 02 GA brand new back in the day. up here in Oh'Canada with some stupid winters we were committed to storing it during the winter months. It sucked making payments on a car we weren't driving in the winter. However, the pay off was well worth it because the vehicle is in terrific shape with lots of life to give long after the final payment was made.

Anyways..... spring time and we are ready to roll. Do my usual tune up. Had to replace the passenger side axle as it began to click during corners at the end of last fall. Changed that yesterday with no problems. now for some reason the car has suffered "partial brake failure" when we put it away last fall all was good. i seriously doubt an axle change would have caused this?

What its doing: I need waaaay more brake pressure then normal to stop. Not like manual brakes and its not acting like a faulty booster ( I know that feeling ) I completely drained the stock fluid and have replaced it with fresh stuff followed by bleeding the lines. I have confirmed no air in the lines but nothing has changed. Double checked front calipers. They are working as they should.

The rear drums seems to be a bit of a mystery. One of them is clicking with engine off, parked and tapping the brake. Almost like one of the adjusters have seized. I suspect this as one drum came off with ZERO effort (if memory serves it usually requires a bit of force to get a drum off) the other drum required a bit of force to remove.

There are no vacuum leaks. i did attempt the back up apply brakes for adjusters and still same. very handy with a wrench and only take my car to shops if necessary (wheel alignments, tire press, etc...)

Would a seized rear adjuster cause my symptoms? Am I on the right track? Stange that the problem would pop up after the car has sat for 4 months? Perhaps that's why I have the problem? sat too long

Starglow
03-25-2013, 06:22 PM
If your statement is true that you COMPLETELY drained the fluid as in ran the master cylinder completely dry then you most likely do still have air in the brake lines. If the ABS controller got air in it then you need a Tech II to hold the actuators open while bleeding the system. A spongy pedal usually means air is in the system somewhere.

Another possibility is the master cylinder seals are bad and not holding pressure which is known as internal bypass. What happens is when you press the brake pedal, the brake fluid gets past the inner seals and you lose fluid pressure. One way to know if this is happening is to remove the master cylinder and check the back side of it for signs of fluid leakage.

The rear brake drums should not drag when the brakes are not being applied. What makes them difficult to remove is if the brake shoes are too tight against the inner drum surface or rust around the center hub area. I had to pull one of my drums off with a gear puller once due to rust even though it otherwise rotated freely. The clicking you hear is probably just the brake springs and shoes moving inside the drum so that is not necessarily abnormal.

Jack the rear end up and have someone apply the brake while you try turning the rear wheels by hand which will give you some indication if the rear brakes are working at all on either one or both sides. Do the same test again but instead with the emergency brake applied to see if both rear wheels are fully locked.

The rear adjusters are self adjusting, but you can tell if one is stuck once you get the drums off to inspect everything. Also check the rear wheel cylinders to make sure they are not leaking brake fluid around the seals.

Lots of things to check, but it;s the only way to narrow down the problem so I hope this helps and good luck! :D

sugar ray
03-26-2013, 12:21 AM
thanks for a very informative post!!

I drained the master cylinder and poured fresh fluid in. the biggest reason was because this problem popped up out of the blue and being that the car is over 11 years old now and still had the stock fluid in, it was long over due. My problem existed "BEFORE" fresh fluid and bleeding.

I was able to confirm the front discs and calipers are working and aren't seized. I have also been able to confirm that NO leaks exist at either the master cylinder or the rear brake cylinders.

I will try your suggestions with an assistant regarding the rear drums. Was just strange to me how one drum required a bit of force to remove and the other slid off instantly, no hesitation like it was barely on there

sugar ray
03-28-2013, 12:20 AM
looks like we have a BINGO!

1 rear adjuster was not connected so it was not adjusting at all. the other adjuster was seized just enough where the kicker would not adjust it. Hence, I had NO back brakes and was running only on fronts.

Perhaps this is my cars way of saying "I hate you for making me sit all winter in a cold garage?" *foshizzle

At any rate, thanks again!:slayer

Starglow
03-28-2013, 05:13 PM
Cool....glad to hear you got it fixed. :applause: