Overflow for brake fluid reservoir?

[175K911]

Has anyone come up with a solution for rerouting the brake fluid reservoir vent? I've generated enough heat that in hard, extended right hand turns on the track the fluid will dribble out the vent hose.... directly onto the left front tire and brake. Not a good thing. I've tried rerouting to a catch can adjacent to the master cylinder and still have the same problem but at least it's not getting on the front rotor. In the course of a full day on the track I can transfer half the brake reservoir to the catch can.

I had this problem with the stock brakes and my Hawk HT10 pads (Motul 600 fluid) and it seems to be a bit worse with the 996TT brakes now. Had the same issue with my previous Carrera too. Not boiling the fluid or loosing brakes, not even close. But generating enough heat that I must be expanding the fluid allowing it to slosh around in the reservoir then move out the vent in the right hand turns.

Any ideas?

[moneymanager]

Can't solve your main problem. But until you do, just run the overflow tube into a small plastic bottle below the reservoir; drain as required.

[SCOTITUDE]

Ive been dealing with that issue forever. no real solution to cure, but now there is a poland spring water bottle wedged in by the booster with a hose drilled thru the cap. I have been using the jerry rigged bottle setup for a while and think maybe its time to replace it with a more suitable looking replacement.

[poc533]

Here's a photo of what put in. The sports bottle is mounted on an aluminum water bottle holder intended for a mountain bike.

[GaryR]

I use one of my Longacre bleed bottles that has a magnet attached and stick it to the steel body in front of my spare, works perfectly and never moves. Even if it fell over it wouldn't leak as it's sealed..

[HarryD]

I route my hose along the fender and through a small hole in the floor pan onto the ground.

[GaryR]

Originally Posted by HarryD

I route my hose along the fender and through a small hole in the floor pan onto the ground.

Yes, dumping it out on the track is a great idea...

[Steve@Rennsport]

Mr. Ed,

Given that everything is "Cause and Effect",...I think the solution is a multi-tiered one.

1) Reduce the heat: I know you have brake cooling but make sure its getting sufficient air. Don't assume the hose placement has no kinks or obstructions and make sure there are no leaks in the hose. Block-off plates in the hubs are effective.

2) Brake pads. Some brands of pads introduce more heat into the caliper pistons, thus add more heat into the fluid. I'm no fan of Hawak pads for this (and other reasons) so I'd kindly suggest a review here,.....

3) Titanium heat plates. I've not used them, but others have had success installed between the pads and caliper pistons. I don't know if there is room or not so this is something to confirm.

Hope this helps,

[HarryD]

Originally Posted by GaryR

Yes, dumping it out on the track is a great idea...

Could be but this duplicates the factory routing for my car.

[Flieger]

I also route mine through a handy hole in the bootom of the smuggler's box. Just the right (small) size for the overflow line.

Not much comes out, just a little drip here and there after sitting after a hard drive where the lateral G's gets it into the overflow tube.

[Mike Metzler]

I think the simple solution is for Ed to slow down!

I have not had this problem (930 brakes, PFC97 pads, cooling ducts with block-off plates). Or, perhaps I just drive too slowly.

[sfoster13]

It will overflow no matter what you do if you drive it hard enough. I have mine routed into a catch bottle in the smugglers box which is zip tied firmly in place. This is nasty stuff and if you're on the track you want a setup that is out of the way and securely fastened in the event of an "off". In the smugglers box, the worst case scenario is that it drains out the drain hole.

[175K911]

Thanks all. I've had so many people over the past xx years tell me they don't have this problem that I was beginning to think I was just nuts. At least I know I'm not alone.

For the moment I think I'll stick with my current setup- an extended hose over to an aluminum catch can attached to my stress bar much like most of you have shown in your pics.

Steve W- I have air coming directly in from the air inlets in the valance, through the Smart Racing manifolds to carbon fiber backing plates behind the rotors. No kinks anywhere except at full lock. Lots of air moving through there. Though I probably ought to put an IR gun or temp patches on the caliper at some point and measure max temps. Of course the solution is the Smart Racing/Fabcar setup we've chatted about.

Mike M- not a chance! I've got to run 10/10's just to keep up with you.

[Sboxin]

We use a small brake fluid bottle as a catch can securely mounted
AND start a track session with a cold half filled reservoir.

[Stophos]

If you get a water bottle with a pull up cap you can remove the plastic in the center and your tube will fit nice and snug. No drilling required.

PS Don't be like that Scottiude guy with the wedging. A simple velcro wrap will do.

[burgermeister]

At 1.2g cornering for the DOT-R crowd, that brake fluid is "level" at a 50 degree angle from horizontal, and any sloshing will only add to that. That will certainly reach the vent hose opening.

I don't have this problem, but if I did my first attempt would be to route the vent hose up and directly over the reservoir to the passenger side of the reservoir, and then to a drain or catchbotttle wherever it is convenient to place. Having the vent hose go up as opposed to some horizontal direction would seem to be directionally correct for reducing fluid loss.

[175K911]

Here's my current setup. I've routed the hose as high as I can and to the rear of the reservoir to avoid or minimize any issue under braking. I'm using an aluminum bottle as the catch can, with a vent hose going straight up. It's tied to the stress bar securely.

(Please ignore the condition of the trunk, the front suspension is off as is the front nose, and the car hasn't been washed since it went up on jack stands a couple months ago.) And to avoid anyone suggesting it, the original 33 bar pressure regulator in the pic is gutted and I'm just using it as an adapter block.

[SCOTITUDE]

Originally Posted by Stophos

PS Don't be like that Scottiude guy with the wedging. A simple velcro wrap will do.

ur such a chooch,
glad to see ur alive.

[175K911]

I have an interesting observation, does this make any sense?
It appears that all the people with this problem are all 915 gearbox people. I've separately heard from a couple of G50 people who don't have the problem. But the G50 reservoir is significantly different because of the clutch hydraulic requirement. Could it be that the fix is as simple as changing to the G50 reservoir and mounting bracket?

[sc_rufctr]

Originally Posted by 175K911

.... Could it be that the fix is as simple as changing to the G50 reservoir and mounting bracket?

I'm curious. Do you have a pic of a G50 reservoir?