Multiple Brake Issues - '87 Carrera

[TwoTarga]

Hello,

I think I may have a couple of brake issues, but it seems odd that I would suddenly have 2 different issues... wanted some of your expert opinions about whether they could be related.

- As far as I know, brakes were totally fine last October.
- Parked it for 5 months, to wait out the dreary Pacific NW winter months.
- Now have both soft brake pedal and brake dragging issues, details below.

Brake pedal: pedal seems fine for a while. After 15-ish minutes of normal driving, the pedal gets soft and I need to pump it once for it to regain normal feel. I did confirm the booster is ok, by depressing the pedal and then starting the car (pedal then falls a bit, which I understand means the booster is good). I checked in both the smuggler box and the pedal cluster areas and see no wetness.

Brake dragging: Basically always drags some, but varies from very mild to somewhat moderate. After driving normally for 15 minutes, I used a thermocouple to check disk temperature of each wheel -- 3 disks were 150F, but the right rear was 230F.

Couple related notes: I don't really know how to check the slave cylinder, so have not yet done that. Clutch feels totally fine.

Thanks for your thoughts!
-Dirk.

[dyerkes]

You don't mention when the brake fluid was last changed, so I would recommend starting with a complete flush of the system.

[faapgar]

Hi,the flexible rubber lines should be replaced every 10 years or so.Longer if you change fluid.The inside rubber in the line swells shut over time and sticks the caliper on.Jack up your right rear after driving and crack the bleeder loose.If the brake turns free the line is the culprit.If not the pistons are sticking in the caliper.Good Luck.Fred

[TwoTarga]

Thank you for the comments. I have only owned the car for 1 year (2k miles), and have done nothing to the brakes in that time. PO reported that he "rebuilt all the brakes", which would have been roughly 2.5 years and 7k miles ago. I suppose that would require a complete flush, but it would not surprise me if he rebuilt the calipers without replacing the lines -- I will definitely try the drive and bleed test that Fred recommended.

Question:
If the brake line is the problem, could that cause the soft pedal issue?

Thank you!!
-Dirk.