What's the answer to rusting discs?
Discussion
I have just been informed by my indy that my front discs need repalcing due to rust on the backs. This is after only 3 years and 15000 miles from having them changed previously for the same reason. The car is driven on an almost daily basis, so not left standing around, and I always dry the brakes off straight after washing the car.
The first set to be changed were genuine Porsche ones and the second set are Pagets. Are there any brands out there that people have had firt hand experience of not rusting overnight?
The first set to be changed were genuine Porsche ones and the second set are Pagets. Are there any brands out there that people have had firt hand experience of not rusting overnight?
I bought my boxster with fairly new discs, but they were going rusty on the inner faces. My garage suggested that when discs are badly corroded, the pads would just polish the rust, not remove it.
I whipped off the discs, removed the worst of the corrosion and then did a few trackdays - that seems to have worked
Even though you are using it every day, you may not be braking very hard, so won't be cleaning up the discs very much.
I whipped off the discs, removed the worst of the corrosion and then did a few trackdays - that seems to have worked
Even though you are using it every day, you may not be braking very hard, so won't be cleaning up the discs very much.mrdemon said:
I would say rubbish
you see 10 year old cars with the same disks
most rust issues are garage queens cars which are washed and put away wet.
my R lives outside, 3.5 years old disks are fine 17k miles.
I would ask why are you getting though disks ? 3 sets in 15k miles !!
That's what I'm asking. If you re read my post you will see my car is anything but a garage queen.you see 10 year old cars with the same disks
most rust issues are garage queens cars which are washed and put away wet.
my R lives outside, 3.5 years old disks are fine 17k miles.
I would ask why are you getting though disks ? 3 sets in 15k miles !!
I've owned many different cars over the years and never gone through discs like this one and that includes competition cars too.
thegoose said:
The car needs driving harder, regularly, then they'll be fine. 
That maybe the answer. It does a couple a track days a year but the rest of the time its being used as my daily. I'll try the Italian brake tune up method on a regular basis from now on and see if that helps. The calipers are in two halves, each with a bleed nipple. They need to be bled equally from both halves.
Most garages will not bother, and only bleed from the outer nipples.
Therefore you have old brake fluid trapped in the inner-half of the caliper.
This results in a better 'compression' on the outer half of the caliper, and less on the inner.
Therefore the inner face of the disk is never swept as well as the outer.
HTH.
Most garages will not bother, and only bleed from the outer nipples.
Therefore you have old brake fluid trapped in the inner-half of the caliper.
This results in a better 'compression' on the outer half of the caliper, and less on the inner.
Therefore the inner face of the disk is never swept as well as the outer.
HTH.
Grease them?
Seriously though, I drive my 996 'properly' when I'm out on a hoon, most of the time I have the family in the car though & I drive it lightly, I am a very light braker.
Had my fronts replaced two years/5000mls ago & was advised on the MoT a couple of weeks ago that the inner faces are rusting again. Rears were advised last year so I started braking heavier & they weren't mentioned this year, guess I'll have to keep it up so the fronts last a bit longer. My local Indie said once they start to rust they go downhill quickly as water can sit in the rust & corrode even quicker.
Washed it last night so took it for a spin to dry the brakes, roads were near empty at 10pm so experimented with braking points, safe to say it stops MUCH quicker than I realised!
Seriously though, I drive my 996 'properly' when I'm out on a hoon, most of the time I have the family in the car though & I drive it lightly, I am a very light braker.
Had my fronts replaced two years/5000mls ago & was advised on the MoT a couple of weeks ago that the inner faces are rusting again. Rears were advised last year so I started braking heavier & they weren't mentioned this year, guess I'll have to keep it up so the fronts last a bit longer. My local Indie said once they start to rust they go downhill quickly as water can sit in the rust & corrode even quicker.
Washed it last night so took it for a spin to dry the brakes, roads were near empty at 10pm so experimented with braking points, safe to say it stops MUCH quicker than I realised!
spyderman8 said:
Totally agree with the above - if the outsides are nice and shiny and corrosion-free and the insides are pitted and flaking, then there's something wrong with the calliper action that needs addressing.
My indy tells me this is a regular thing and 3 to 4 years is about the average lifespan of discs on Porsches, certainly in terms of the inner face rusting at least. He has checked the caliper action and is happy all is well. I try not to direct a hose at the brakes when washing the car for the very reason of trying to avoid rust on the inside of the discs. I have found this to be a problem with most cars that have large drilled ventilated discs. They simply don't get hot enough with light use.
IF I do soak them, I take the car for a run and drive with my foot gently on the brake, causing the discs to get hot enough to boil water from the discs and pads. An Italian tune up does exactly the same but it is not always convenient to go for a hoon just to dry the brakes.
A garage with poor ventilation and no membrane in the floor also contributes greatly to the problem.
IF I do soak them, I take the car for a run and drive with my foot gently on the brake, causing the discs to get hot enough to boil water from the discs and pads. An Italian tune up does exactly the same but it is not always convenient to go for a hoon just to dry the brakes.
A garage with poor ventilation and no membrane in the floor also contributes greatly to the problem.
I have the exact same issue on my 996. Daily driver, dry the brakes after washing with a decent drive, but just had to get mine replaced due to MOT failure. Why are the discs on my wife's A6 not corroded after 6 years? She doesn't do track days in it, or use heavy braking. Both cars are washed as much as the other and both discs get the same amount of water on them.
I don't know if there is any truth to what my indy said, but he inferred that the brake cooling ducts point all the air at the inside face of the brake disks. Hence, if you drive in the rain your disks are permanently wet on the inside face. Add to which this is the time when the Italian brake test cannot be done so safely.
Furthermore, in the winter, any spray from the road will also be loaded with salt and you have an instant rust recipe.
I equally have no idea whether Meyle brake disks sold on eBay by http://www.ebay.co.uk/itm/PORSCHE-BOXSTER-CAYMAN-3...
have any real benefit but they carry a 2 year anti-corrosion warranty. Unfortunately, Meyle don't do them to fit a 2.9l Cayman (2011 model).
Furthermore, in the winter, any spray from the road will also be loaded with salt and you have an instant rust recipe.
I equally have no idea whether Meyle brake disks sold on eBay by http://www.ebay.co.uk/itm/PORSCHE-BOXSTER-CAYMAN-3...
have any real benefit but they carry a 2 year anti-corrosion warranty. Unfortunately, Meyle don't do them to fit a 2.9l Cayman (2011 model).
Have to agree with urban achiever...my cars are in regular use ( at least three/ four times weekly) ..My 996 needed 3 sets of discs in 60k and now my 997 on second set in 25k . I am definately not a gentle braker and all replaced through corrosion on inside face. My polo gti has done 125k and is on second set of discs , replaced as originals were worn thin. These cars are driven by the same people ,same journeys , same driving style, how come the difference?....my thoughts are Porche discs ( originals or aftermarket ,I've tried both) are made from very cheap materials. Condensors and radiators ....same poor quality materials that disintegrated on a 5 year cycle. Thank god the driving thrills these cars offer sweeten the bad points. As an answer to stopping discs rusting...move to Spain!
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