Front piston seal damage

[Lojs]

Was swapping my front RS29s today and noticed that on both sides the outer piston seals look damaged, especially the bottom ones. The inner side is fine.
Why has this happened? Overheating?
How bad is this? Do I need to have it repaired immediately?
Is it possible to repair the seals only without having to replace the whole caliper?

[Don Molina]

Of course you don't need to change the whole caliper.

Seals are dirt cheap, and not that bad to do a rebuild. Last spring I rebuild 1 caliper in my previous Lexus, and all of the calipers in my S2000.

However seeing that with less than 100k miles is odd to say the least.

In any case, have them fix it asap to save the piston with the damaged seal. If dust and humidity goes in it screws up the piston and then (after a long abuse) it seizes. Even if the piston is screwed (surface beyond polishing) then you can get one for not insane money, so again no biggie.

[kitesurfer]

Those are the outer dust boots in the pictures , the piston seal is a square cut seal inside the caliper that you can access when the piston is removed. Replacing the dust boots is not too bad and pretty cheap if you decide to DIY. If you go for a total rebuild than replace the piston seal also

[robbo mcs]

The dust seals are really a consumable item on track cars. They get worn and need replacing every now and again.

For steel brakes you need the repair kit, pn 34116850935

That is number 12 in this diagram from real oem

http://www.realoem.com/bmw/enUS/show...diagId=34_2199

[Lojs]

Originally Posted by robbo mcs

The dust seals are really a consumable item on track cars. They get worn and need replacing every now and again.

For steel brakes you need the repair kit, pn 34116850935

That is number 12 in this diagram from real oem

http://www.realoem.com/bmw/enUS/show...diagId=34_2199

Thanks! I just found it myself like 3 mins ago. )) Cost seems to be ok.
Is there a DIY for this?

[HP Autosport]

Inspect and replace when required.

Heat is your enemy.

[190hpkilla]

Originally Posted by HP Autosport

Inspect and replace when required.

Heat is your enemy.

The repair kit doesn't come with piston seals. You need to pop the piston out to properly install the dust boots. Good idea to get new seals as well.

Anyone know where to purchase the piston seal?

[Lojs]

Originally Posted by 190hpkilla

The repair kit doesn't come with piston seals. You need to pop the piston out to properly install the dust boots. Good idea to get new seals as well.

Anyone know where to purchase the piston seal?

yeah, I purchased the kit, it consists of 4 pieces of dust boots only. which is exactly what I needed.
Are you 100% sure I have to take the caliper apart to replace them? have you done it before on this model?

[HP Autosport]

Originally Posted by 190hpkilla

The repair kit doesn't come with piston seals. You need to pop the piston out to properly install the dust boots. Good idea to get new seals as well.

Anyone know where to purchase the piston seal?

If just the boots are bad, you are fine. New boots will turn out the same after your next track day.

Race calipers don't use the boots for this same reason(heat will destroy any dust boot). What you have to do is just to keep up with the bleeding and flushing of the brake fluid. Yes, without dust boots there is a higher chance of foreign elements entering the brake hydraulic system, but the bleed and/or flush will get most of not all of it out. That is why race teams will do a complete flush after each test/race day. The seals should last a long time as long as you stick to a good bleed/flush schedule.

[r0b3r]

delete please

[Kung Fu English]

Did this ever get resolved? I am having the same issue.

Are the high temp gray or blue dust boots worth getting installed? I read the blue ones you have to be careful with the brake fluid, is this true?

[Lojs]

Originally Posted by Kung Fu English

Did this ever get resolved? I am having the same issue.

Are the high temp gray or blue dust boots worth getting installed? I read the blue ones you have to be careful with the brake fluid, is this true?

I replaced them with OEM ones. It was very hard, but I managed to replace without dismounting the calipers, just took out the pads. However I do not recommend this as I scratched the caliber paint a lot.

Needless to say they got destroyed again after a few trackdays, so quite pointless to put back OEM. I have no experience with upgraded ones.