Brakes after winter hibernation

[aknapp]

'89 911 was stored from November until today.

In November, all was well with the brakes - firm pedal, no leaks, etc.

Today, the pedal goes 80% of full travel, then it's firm enough to lock the front brakes. Throughout the first 80%, there is little braking effect, but there is a small amount.

Fluid is full, no leaks on the garage floor.

I searched and found nothing similar.

Any ideas? If you need more info to diagnose, post it here!

Thanx!

[kodioneill]

Doe's it come up when you pump it?

[aknapp]

No, pressure never builds.

Based on the the threads I found during search, I thought it might be bad master cylinder seals. Could these go bad while sitting in hibernation?

[aknapp]

More info:
- pressure builds slightly with car off, but it goes away after starting.
- new pads and rotor 3 years ago, but I've only driver it about 1000 miles since. Work done at shop that replaced with Akebono pads. Pedal wash slightly softer than with original (Porsche?) pads, but I attributed that to the pads (maybe not?).

Another short test drive - once it goes through the lengthy travel, it almost feels "normal".

Crappy pads? Not fully bled, and now there is moisture in the lines?

[aknapp]

Also, any recommendations for good repair shop in the far west suburbs of Chicago (Naperville)? Anyone have experience with Performancewerks in Naperville?

[RSTarga]

bad servo?

[Guardsred911]

Boy, I would just bleed it and see how that works out

[Jdub]

I would not worry yet, that is, unless the car is unsafe to drive right now.

Your brakes are experiencing stiction, or a reluctance to move easily (brake pucks and MC seals). Some of this is simply sitting over time, but the brake job you had 1,ooo miles ago essentially reset the location of the pucks in the brake body by putting in thicker pads. Brake pucks that had years to wisen to the new bit of surface exposed as your pads thinned were suddenly pushed right back into the caliper body and everyone needs time to seat up.

When you cannot get pressure, something is not returning to its original position.* If you calculate calipers X4 and possibly the MC as well this would result in something like what you are feeling.

If, again, the car is safe to drive I would take it out and exercise it with some very easy driving and braking around a nice town on a Sunday morning with a decent breakfast. See how the car feels after a few hours of driving and see if the feel has not improved. May take longer but...

Finally, a brake bleed is never a bad idea, and in this case, would certainly let you exercise those pucks much more than a drive. Worth considering.

* EDIT: ONLY if you are not bleeding fluid!!! Assumes a closed system if you get my drift.

[ian s]

I think exercising the car a bit (if safe to drive) is probably a good idea.
In your area I think the best guys around are Fischer automotive in Barrington on northwest highway. The owner has been working on Porsches since the 60's and worked for a friend of mines father for many years before he went off on his own in the 80's. You know your in the right shop when the guy has a german accent so thick you really have to listen. The kid is super sharp too. They also have an active racing team so these guys are definite porsche nuts!

good luck and happy spring!

[aknapp]

Earlier tonight, I noticed a faint metallic clunk when pushing the brake pedal. I think it may be time to take to a shop.

[Tremelune]

Originally Posted by aknapp

- new pads and rotor 3 years ago, but I've only driver it about 1000 miles since.

I just bought a car that saw about 2k miles in five years. All of the issues I'm taking care of are from the car not being driven enough. It will cost the same whether you drive the car or not, so you might as well drive it.