follow ft86club on our blog, twitter or facebook.
FT86CLUB
Ft86Club
86SPEED
Register Garage Members List Calendar Search Today's Posts Mark Forums Read

Go Back   Scion FR-S Forum | Subaru BRZ Forum | Toyota 86 GT 86 Forum | AS1 Forum - FT86CLUB > Technical Topics > Issues | Warranty | Recalls / TSB

Issues | Warranty | Recalls / TSB Problems, issues, recalls, TSBs


User Tag List

Reply
 
Thread Tools Search this Thread
Old 08-24-2019, 06:19 PM   #1
EndlessAzure
Senior Member
 
EndlessAzure's Avatar
 
Join Date: May 2017
Drives: '14 FR-S [37J] | Daily/Track
Location: Los Angeles
Posts: 316
Thanks: 49
Thanked 113 Times in 92 Posts
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Garage
Advice for leaked brake fluid from front lower caliper pin?

Hey all,



I recently returned from the track. This weekend while doing some maintenance, I noticed a small residue pool covered with dirt in the barrel of my Pass Front wheel.



After closer inspection, I noticed a dried dribble of yellow/orange fluid that appears to have come from the lower pin on the Pass Front brake caliper. There wasn't any other signs indicating that it could be motor oil or damper fluid.


The leak didn't appear to be continuous or ongoing as there was only a small pool on the wheel instead of a widespread spattering.


It may have occurred when I dropped the wheel off the track or caused by fluid boiling while the car sat in the paddock, as I got the brakes hot enough for them to be smoking. I didn't appear to have any issues on track or now with brake pressure. The caliper doesn't appear to be stuck either. The track was run CCW, so more stress on the passenger side is expected.



I'm going to continue to monitor for leaks and pull the pin to see if there are any issues. Would you all have any insight on what I should look for, precautions, or actions to take?


Thanks!


Standard 2 piston, Project Mu Club Racer Advance, Motul RBF 600
__________________

Last edited by EndlessAzure; 08-25-2019 at 12:18 AM.
EndlessAzure is offline   Reply With Quote
Old 08-24-2019, 07:50 PM   #2
soundman98
Boost is Whack. N/A4LYFE
 
soundman98's Avatar
 
Join Date: Sep 2013
Drives: '14 brz limited
Location: chicagolandia
Posts: 2,255
Thanks: 3,563
Thanked 1,569 Times in 957 Posts
Mentioned: 21 Post(s)
Tagged: 0 Thread(s)
brembo's or standard dual-piston calipers?

i wipe it down, and keep a very close eye on both it and the fluid reservoir for the next few weeks.

yellow orange is an odd color for brake fluid unless it's contaminated-- it's also possible that some of the bearing grease in that front hub might have liquefied from the temps and the caliper was the lowest point to drip down off of.
__________________
my '14 brz limited "the return to normal" (or is it?)
led mods-10%(planning/designing/sitting on hands)audio mods-99%(done is never done)

hidplanet build log
soundman98 is offline   Reply With Quote
The Following 2 Users Say Thank You to soundman98 For This Useful Post:
EndlessAzure (08-24-2019), humfrz (08-25-2019)
Old 08-24-2019, 10:03 PM   #3
EndlessAzure
Senior Member
 
EndlessAzure's Avatar
 
Join Date: May 2017
Drives: '14 FR-S [37J] | Daily/Track
Location: Los Angeles
Posts: 316
Thanks: 49
Thanked 113 Times in 92 Posts
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Garage
Quote:
Originally Posted by soundman98 View Post
brembo's or standard dual-piston calipers?

i wipe it down, and keep a very close eye on both it and the fluid reservoir for the next few weeks.

yellow orange is an odd color for brake fluid unless it's contaminated-- it's also possible that some of the bearing grease in that front hub might have liquefied from the temps and the caliper was the lowest point to drip down off of.
Bearing grease is a good possibility. The residue on the wheel was pretty thick, way thicker than brake fluid would be, now that I think about it. And that could be why it didn't sling



I'll check the brake fluid reservoir. If I lost any it would be quite apparent
__________________

Last edited by EndlessAzure; 08-24-2019 at 10:40 PM.
EndlessAzure is offline   Reply With Quote
Old 08-24-2019, 10:44 PM   #4
gravitylover
Senior Member
 
Join Date: Nov 2014
Drives: 2013 BRZ Premium 6MT White
Location: SE NY
Posts: 1,214
Thanks: 782
Thanked 484 Times in 356 Posts
Mentioned: 6 Post(s)
Tagged: 1 Thread(s)
I'd probably flush that fluid if the brakes were hot enough to be smoking. You might also check to see if the pads are glazed.
__________________
gravitylover is offline   Reply With Quote
Old 08-25-2019, 12:19 AM   #5
EndlessAzure
Senior Member
 
EndlessAzure's Avatar
 
Join Date: May 2017
Drives: '14 FR-S [37J] | Daily/Track
Location: Los Angeles
Posts: 316
Thanks: 49
Thanked 113 Times in 92 Posts
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Garage
Quote:
Originally Posted by gravitylover View Post
I'd probably flush that fluid if the brakes were hot enough to be smoking. You might also check to see if the pads are glazed.

Yeah I'll check. I'm not too concerned since they're track pads and fluid.
__________________
EndlessAzure is offline   Reply With Quote
The Following User Says Thank You to EndlessAzure For This Useful Post:
gravitylover (08-25-2019)
Old 08-25-2019, 04:26 AM   #6
EndlessAzure
Senior Member
 
EndlessAzure's Avatar
 
Join Date: May 2017
Drives: '14 FR-S [37J] | Daily/Track
Location: Los Angeles
Posts: 316
Thanks: 49
Thanked 113 Times in 92 Posts
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Garage
@gravitylover @soundman98


Pads seem fine. Fluid reservoir is a tiny bit lower than before track day, but I chalk that to pad wear.


Lucky for me, I broke a stud off in the process of swapping back to my street wheels. I took the chance to pulled the caliper out and take some pictures. See below for images.


I couldn't identify any clear grease trail from the wheel hub. Seems pretty localized to the caliper pistons and lower caliper pin. It might be the rubber grease from inside the caliper pin.
























__________________
EndlessAzure is offline   Reply With Quote
Old 08-25-2019, 05:02 AM   #7
Mr.ac
[insert cool phrase here]
 
Mr.ac's Avatar
 
Join Date: Aug 2015
Drives: BRZ Premium
Location: Central Coast CA
Posts: 2,053
Thanks: 545
Thanked 1,267 Times in 772 Posts
Mentioned: 25 Post(s)
Tagged: 0 Thread(s)
Car is 100% fucked.
Burn car, it's not worth fixing at all.
Should have bought a better car.













Joking aside, simple answer is your brakes cooked the grease to its melting point, thus flowing the path of lest resistance and just oozed out a bit.
If it makes you feel better buy new boots and re lube those pins.
__________________
New daily driver - Subaru BRZ Premium
Weekend fun/track car - '91 MR2 Turbo Gen3
Old daily driver - '88 MR2 Supercharged
Mr.ac is offline   Reply With Quote
The Following 2 Users Say Thank You to Mr.ac For This Useful Post:
EndlessAzure (08-25-2019), Grady (08-26-2019)
Old 08-25-2019, 08:14 AM   #8
RZNT4R
Professional Mechanic
 
Join Date: Apr 2010
Drives: 2017 86 6MT Oceanic
Location: Quebec, Canada
Posts: 296
Thanks: 8
Thanked 185 Times in 116 Posts
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
It is likely to be rust from a wet rotor transferring to the pad and dripping down on the rack.

Btw, the rust on the hub is horrific. Wheel hubs should be spotlessly clean and receive a thin coat of high temp grease to prevent rust from setting back in (I like either lithium grease or the permatex silicon-ceramic orange stuff, gray anti-seize goes on too thick and dries out too fast). Rust scales on a hub almost always put you out of spec for lateral runout on the rotor and are a frequent cause of wheel tightening issues.

But you have more pressing issues: one of the piston dust boots visible in your pic seems torn, and the friction material on the pad turning white is a sign the pad is being massively overheated, I usually see pads that color when I service neglected brakes that are totally seized. The fingers on the outer side of the caliper are also starting to change color, there is way too much heat being put into these brakes.
RZNT4R is offline   Reply With Quote
The Following User Says Thank You to RZNT4R For This Useful Post:
EndlessAzure (08-25-2019)
Old 08-25-2019, 12:54 PM   #9
EndlessAzure
Senior Member
 
EndlessAzure's Avatar
 
Join Date: May 2017
Drives: '14 FR-S [37J] | Daily/Track
Location: Los Angeles
Posts: 316
Thanks: 49
Thanked 113 Times in 92 Posts
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Garage
Quote:
Originally Posted by RZNT4R View Post
It is likely to be rust from a wet rotor transferring to the pad and dripping down on the rack.

Btw, the rust on the hub is horrific. Wheel hubs should be spotlessly clean and receive a thin coat of high temp grease to prevent rust from setting back in (I like either lithium grease or the permatex silicon-ceramic orange stuff, gray anti-seize goes on too thick and dries out too fast). Rust scales on a hub almost always put you out of spec for lateral runout on the rotor and are a frequent cause of wheel tightening issues.

But you have more pressing issues: one of the piston dust boots visible in your pic seems torn, and the friction material on the pad turning white is a sign the pad is being massively overheated, I usually see pads that color when I service neglected brakes that are totally seized. The fingers on the outer side of the caliper are also starting to change color, there is way too much heat being put into these brakes.

The rust could certainly explain the color. However, I think it's more than just water runoff here. I live in a very dry area (High Desert of Southern California), and the residue was for sure oily. If it were just water run-off, it would be dry and flaky like the rest of the components.

Thanks for that. I clean the hubs with wire brush and put antiseize on them when I can. The rust is unavoidable simply due to heat and enclosed environment. Wheel cleaner probably doesn't help either. I'll try a thicker grease and perhaps touch up with primer.

These see the track regularly, and that's the price to be paid. My pads (race pads meant to see the heat) always get their lettering seared off after the first outing. My friends were reporting the rotors were glowing faint red in the day time. The piston boots will never survive in that kind of environment. The pads work fine and still bite like they were new. There isn't anything more I can really do to help that other than take longer time cooling the car down and add temperature monitoring tape
__________________

Last edited by EndlessAzure; 08-25-2019 at 01:41 PM.
EndlessAzure is offline   Reply With Quote
Old 08-25-2019, 02:43 PM   #10
RZNT4R
Professional Mechanic
 
Join Date: Apr 2010
Drives: 2017 86 6MT Oceanic
Location: Quebec, Canada
Posts: 296
Thanks: 8
Thanked 185 Times in 116 Posts
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Well if that is the case, you're probably melting the slide pin grease.

Maybe you should look into some brake cooling ducts because they're definitely not having fun being heated like that.
RZNT4R is offline   Reply With Quote
The Following User Says Thank You to RZNT4R For This Useful Post:
EndlessAzure (08-25-2019)
Old 08-25-2019, 03:44 PM   #11
soundman98
Boost is Whack. N/A4LYFE
 
soundman98's Avatar
 
Join Date: Sep 2013
Drives: '14 brz limited
Location: chicagolandia
Posts: 2,255
Thanks: 3,563
Thanked 1,569 Times in 957 Posts
Mentioned: 21 Post(s)
Tagged: 0 Thread(s)
yeah, the piston boots are definitely starting to crack, a piston leak isn't that far into your future.

if your'e tracking the car consistently, track-spec calipers would definitely be a worthwhile cost.
__________________
my '14 brz limited "the return to normal" (or is it?)
led mods-10%(planning/designing/sitting on hands)audio mods-99%(done is never done)

hidplanet build log
soundman98 is offline   Reply With Quote
The Following User Says Thank You to soundman98 For This Useful Post:
EndlessAzure (08-26-2019)
Old 08-26-2019, 08:27 AM   #12
RZNT4R
Professional Mechanic
 
Join Date: Apr 2010
Drives: 2017 86 6MT Oceanic
Location: Quebec, Canada
Posts: 296
Thanks: 8
Thanked 185 Times in 116 Posts
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Since the calipers have yet to actually fail, it's probably more economical to rebuild them: Piston seals and boots can be had for a very low cost, and while they're torn down, it would be a good opportunity for high temp paint to protect them, then going forwards, this seems like the exact thing that would be needed.

http://www.ft86speedfactory.com/velo...l#.XWPOinVKiUk
RZNT4R is offline   Reply With Quote
Old 08-26-2019, 01:51 PM   #13
DandoX
Senior gif poster
 
DandoX's Avatar
 
Join Date: Jun 2013
Drives: 2013 Asphalt FRS
Location: Ca, SoCal
Posts: 814
Thanks: 510
Thanked 574 Times in 329 Posts
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Garage
Quote:
Originally Posted by RZNT4R View Post
Well if that is the case, you're probably melting the slide pin grease.

Maybe you should look into some brake cooling ducts because they're definitely not having fun being heated like that.
^
I agree
It looks like your cooked the grease in the guide pins. Or possible your bleeder valve was not torqued to spec?
I would make sure the guide pins can freely move, then make sure they are greased properly (with the right silicon based grease), clean the boots and make sure no damage is there. Also take out the guide pins and inspect those for any signs of wear or damage.


Quote:
Originally Posted by soundman98 View Post
yeah, the piston boots are definitely starting to crack, a piston leak isn't that far into your future.
They don't look too bad to me. Are you talking about the piston boots or the guide pin boot?
DandoX is offline   Reply With Quote
Old 08-26-2019, 02:17 PM   #14
EndlessAzure
Senior Member
 
EndlessAzure's Avatar
 
Join Date: May 2017
Drives: '14 FR-S [37J] | Daily/Track
Location: Los Angeles
Posts: 316
Thanks: 49
Thanked 113 Times in 92 Posts
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Garage
Quote:
Originally Posted by DandoX View Post
^
I agree
It looks like your cooked the grease in the guide pins. Or possible your bleeder valve was not torqued to spec?
I would make sure the guide pins can freely move, then make sure they are greased properly (with the right silicon based grease), clean the boots and make sure no damage is there. Also take out the guide pins and inspect those for any signs of wear or damage.




They don't look too bad to me. Are you talking about the piston boots or the guide pin boot?
I pulled both top and bottom pins, cleaned them, and put new OE rubber grease. Pins themselves looked okay. The lower rubber guide bushing was fraying, so I replaced it.

I think they are talking about the caliper piston boots.

Ordered some GT3 brake ducts to help with the cooling
__________________
EndlessAzure is offline   Reply With Quote
 
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
SOLD: FS 2004 STI Front Brembo Brake Caliper and more Kayysonie Brakes, Suspension, Chassis 11 06-19-2017 08:36 AM
Stoptech S/S brake lines: same between stock caliper vs big brake kit? mav1178 Suspension | Chassis | Brakes -- Sponsored by 949 Racing 11 05-10-2016 07:14 PM
Darker front brake fluid EZBRZY Mechanical Maintenance (Oil, Fluids, Break-In, Servicing) 6 09-09-2015 05:55 PM
Front Brake Caliper Piston Rebuild? smbstyle Mechanical Maintenance (Oil, Fluids, Break-In, Servicing) 0 10-17-2013 05:18 PM
Secondary Rear Brake Caliper for drifting or parking brake?? (pics) Axel Scion FR-S / Toyota 86 GT86 General Forum 20 02-25-2010 11:28 AM


All times are GMT -4. The time now is 01:41 AM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
Garage vBulletin Plugins by Drive Thru Online, Inc.