caliper bleeding valve leak in OTD

tmalaquin · 07-16-2018, 09:27 PM

Hi there !

After OTD events I notice a leak on my front calipers bleeding valves.

It happened during my 1st OTD just after I changed to DOT 4 (RTF 600) at 2500 miles, then stopped leaking during 2000 miles of daily drive, therefore I thought it was just a leftover in the bleed valve. However this weekend it happened again during the 2nd OTD, car has now 4500 miles.

I did not notice any brake issue or loose pedal during heavy braking, and fluid volume was between min and max witness mark all day long....
but i believe it's abnormal to loose a little fluid thought the bleed valve during braking.... What do you think ? did you guys face the same issue ?

Also, the engine did not overheat but I consumed a fair amount of oil (from max to nominal witness mark) although the engine is not in brake in period anymore... any thoughts ?

Besides the 1LE handled beautifully

Thanks in advance for your guidance !

Mountain · 07-16-2018, 11:39 PM

Are you sure its not residual fluid that got trapped in the bleeder screw dust caps from after bleeding?

I’ve had it happen where the extreme heat cause residual fluid to be push out from the dust cap.

Move_Over · 07-17-2018, 06:19 AM

Almost positive it was residual fluid. Same thing happened to me, the dust cover cane offf and there was some fluid around my wheel barrel and down the side of the caliper. The fact that tour resivior level did not decrease should tell you there is no leak. If it was leaking your pedal would be getting soft as you’d be losing hydraulic pressure.

tmalaquin · 07-17-2018, 08:09 AM

thanks for the answers !
Well the first time it happened I thought about residual fluid... so I cleaned the caliper / bleed valve and rubber cap. did not happen again during DD

however it happened during second track day again... I did no flush / bleed brake fluid in between the 2 track days. So i believe there was no more residual fluid

is it possible that the nipple valve loose its sealing property under extreme heat ?
maybe a bad thread/ tap tolerance ?

Move_Over · 07-17-2018, 09:59 AM

Quote:

Originally Posted by tmalaquin

thanks for the answers !
Well the first time it happened I thought about residual fluid... so I cleaned the caliper / bleed valve and rubber cap. did not happen again during DD

however it happened during second track day again... I did no flush / bleed brake fluid in between the 2 track days. So i believe there was no more residual fluid

is it possible that the nipple valve loose its sealing property under extreme heat ?
maybe a bad thread/ tap tolerance ?

Highly doubtful, if that was happening you'd feel it in your pedal and you'd slowly be losing fluid. Is your fluid level going down?I would mark where your level is on the reservoir and if it's not going down, you simply cannot be losing fluid.

I had the same exact thing happen on saturday, stopped, then it started from the other side of the caliper later on the afternoon. those caps can hold a deceptive amount of fluid and it makes it look much worse when they come off and starts dripping. I was not losing any brake pedal feel, nor was i losing any fluid out of the reservoir.

zx9rmal · 07-17-2018, 10:06 AM

When I would bleed brakes on my bikes, there would always be fluid left inside the valve. I always took a paper towel, rolled up the corners very small and inserted it into the valve to absorb the residual fluid. A small amount of fluid can spread all over the place.

Move_Over · 07-17-2018, 10:15 AM

Quote:

Originally Posted by zx9rmal

When I would bleed brakes on my bikes, there would always be fluid left inside the valve. I always took a paper towel, rolled up the corners very small and inserted it into the valve to absorb the residual fluid. A small amount of fluid can spread all over the place.

Another thing you can do is take some compressed air to dry out the bleeder valve, however make sure you hold a towel tightly over so it doesnt blow all over the place.

Whitespeed · 07-17-2018, 10:34 AM

Snug up your bleeder screws a little more. Or back off and retighten to reseat the screw. Under heavy/repeated braking a small amount is liking seeping past. It won't necessarily be enough to see a noticeable change in the reservoir fluid level, but it can still make a mess.

I use a pipe cleaner to clean out the nipples after bleeding.

As for your oil level, I don't want to cause alarm, but after 3 track days and 2500 miles, my oil level has not dropped at all.

AZ_1LE · 07-17-2018, 12:04 PM

It's NOT always "residual fluid in the bleeder." I was getting fluid weeping out of the bleeders at Chuckwalla, and this was after I had sprayed all of the bleeders out with brake parts cleaner and compressed air. They were 100% dry before the track day started.

To get them to stop weeping, I had to tighten them past my comfort level, and past the 9-12 ft lbs (120 in lbs) recommended torque value. It seems GT350 owners have the same problem, for what it's worth.

Move_Over · 07-17-2018, 12:41 PM

Quote:

Originally Posted by AZ_1LE

It's NOT always "residual fluid in the bleeder." I was getting fluid weeping out of the bleeders at Chuckwalla, and this was after I had sprayed all of the bleeders out with brake parts cleaner and compressed air. They were 100% dry before the track day started.

To get them to stop weeping, I had to tighten them past my comfort level, and past the 9-12 ft lbs (120 in lbs) recommended torque value. It seems GT350 owners have the same problem, for what it's worth.

Good to know...Thanks

Alpha1BC · 07-17-2018, 01:01 PM

Torque for the bleeder valves I see for the SS and SS 1LE in the service manual is a little bit higher at 13-15 ft-lb (17-20 Nm).

Another alternative to consider would be some of this stuff. Worked for a friend of mine to fix the same issue on CTS-V calipers (essentially same design as ours) and seems to last a while through multiple brake bleeds (he bleeds after every track event).

tmalaquin · 07-17-2018, 01:04 PM

Thanks for the recommendation y'all, I will clean them and tighten them to 20 Nm this weekend, and check on the next OTD...
I just noticed that I lost one inboard cap so it must have been weeping there as well.

As far as the oil consumption, Despite Whitespeed's statement I am hoping it's normal process to have oil consumption during OTD when weather is hot (90F), and you push hard on the throttle.
What is a normal oil consumption during OTD / HPDE? (engine never overheated, 3/4 of oil temp gauge)

Alpha1BC · 07-17-2018, 01:12 PM

Quote:

Originally Posted by tmalaquin

Thanks for the recommendation y'all, I will clean them and tighten them to 20 Nm this weekend, and check on the next OTD...
I just noticed that I lost one inboard cap so it must have been weeping there as well.

As far as the oil consumption, Despite Whitespeed's statement I am hoping it's normal process to have oil consumption during OTD when weather is hot (90F), and you push hard on the throttle.
What is a normal oil consumption during OTD / HPDE? (engine never overheated, 3/4 of oil temp gauge)

I'll typically lose that much oil over the course of a season, but not in one session. I'd not personally be concerned at this point, just based on tolerances some engines will burn more than others.

At a minimum I recommend keeping an eye on your oil level more than usual to make sure it doesn't get any worse, keep an eye on your coolant reservoir (the lower one) to make sure it's not turning brown, and keep an eye on your oil during changes to make sure it's not milky or otherwise discolored to make sure you're not mixing oil and coolant somewhere. An extra layer of safety could be to do an oil analysis through Blackstone labs or something like that to give you a little more information.

tmalaquin · 07-17-2018, 02:09 PM

[QUOTE=Alpha1BC;10252952]I'll typically lose that much oil over the course of a season, but not in one session. I'd not personally be concerned at this point, just based on tolerances some engines will burn more than others.

At a minimum I recommend keeping an eye on your oil level more than usual to make sure it doesn't get any worse, keep an eye on your coolant reservoir (the lower one) to make sure it's not turning brown, and keep an eye on your oil during changes to make sure it's not milky or otherwise discolored to make sure you're not mixing oil and coolant somewhere. An extra layer of safety could be to do an oil analysis through Blackstone labs or something like that to give you a little more information.[/QUOTE

Thanks ALPH1BC

To clarify the volume went from max to nominal on the oil height gauge, during 1h20 total track session at M1 concourse. Oil is valvoline synpower MST 5W40.
I will check all the item listed above on a regular basis and potentially do an oil analysis

Cheers,
T

07-16-2018, 09:27 PM	#1
tmalaquin Drives: Blue ss 1le 18 Join Date: Apr 2018 Location: NoCal Posts: 67	caliper bleeding valve leak in OTD Hi there ! After OTD events I notice a leak on my front calipers bleeding valves. It happened during my 1st OTD just after I changed to DOT 4 (RTF 600) at 2500 miles, then stopped leaking during 2000 miles of daily drive, therefore I thought it was just a leftover in the bleed valve. However this weekend it happened again during the 2nd OTD, car has now 4500 miles. I did not notice any brake issue or loose pedal during heavy braking, and fluid volume was between min and max witness mark all day long.... but i believe it's abnormal to loose a little fluid thought the bleed valve during braking.... What do you think ? did you guys face the same issue ? Also, the engine did not overheat but I consumed a fair amount of oil (from max to nominal witness mark) although the engine is not in brake in period anymore... any thoughts ? Besides the 1LE handled beautifully Thanks in advance for your guidance !

07-17-2018, 10:06 AM	#6
zx9rmal Drives: '20 ZL1 M6 Join Date: Apr 2017 Location: FT. Lauderdale, FL Posts: 717	When I would bleed brakes on my bikes, there would always be fluid left inside the valve. I always took a paper towel, rolled up the corners very small and inserted it into the valve to absorb the residual fluid. A small amount of fluid can spread all over the place. __________________ Mal Ft. Lauderdale, FL '20 Camaro ZL1 M6 '22 Kawasaki ZX-14R

07-17-2018, 12:04 PM	#9
AZ_1LE Drives: 2019 ZL1 1LE Join Date: Feb 2017 Location: Gilbert, AZ Posts: 645	It's NOT always "residual fluid in the bleeder." I was getting fluid weeping out of the bleeders at Chuckwalla, and this was after I had sprayed all of the bleeders out with brake parts cleaner and compressed air. They were 100% dry before the track day started. To get them to stop weeping, I had to tighten them past my comfort level, and past the 9-12 ft lbs (120 in lbs) recommended torque value. It seems GT350 owners have the same problem, for what it's worth. __________________ Old: 2017 SS 1LE Old: 2017 ZL1 Current: 2019 ZL1 1LE

07-17-2018, 01:01 PM	#11
Alpha1BC Drives: 2017 1SS 1LE Join Date: Jun 2016 Location: Detroit, MI Posts: 1,001	Torque for the bleeder valves I see for the SS and SS 1LE in the service manual is a little bit higher at 13-15 ft-lb (17-20 Nm). Another alternative to consider would be some of this stuff. Worked for a friend of mine to fix the same issue on CTS-V calipers (essentially same design as ours) and seems to last a while through multiple brake bleeds (he bleeds after every track event). __________________ 2017 SS 1LE.

07-16-2018, 11:39 PM	#2
Mountain Drives: 2017 SS 1LE, 2016 1SS (previous) Join Date: Apr 2016 Location: Metro-Detroit Posts: 1,863	Are you sure its not residual fluid that got trapped in the bleeder screw dust caps from after bleeding? I’ve had it happen where the extreme heat cause residual fluid to be push out from the dust cap.

07-17-2018, 06:19 AM	#3
Move_Over Drives: ISO ss 1le Join Date: May 2018 Location: FL Posts: 764	Almost positive it was residual fluid. Same thing happened to me, the dust cover cane offf and there was some fluid around my wheel barrel and down the side of the caliper. The fact that tour resivior level did not decrease should tell you there is no leak. If it was leaking your pedal would be getting soft as you’d be losing hydraulic pressure.

07-17-2018, 08:09 AM	#4
tmalaquin Drives: Blue ss 1le 18 Join Date: Apr 2018 Location: NoCal Posts: 67	thanks for the answers ! Well the first time it happened I thought about residual fluid... so I cleaned the caliper / bleed valve and rubber cap. did not happen again during DD however it happened during second track day again... I did no flush / bleed brake fluid in between the 2 track days. So i believe there was no more residual fluid is it possible that the nipple valve loose its sealing property under extreme heat ? maybe a bad thread/ tap tolerance ?

07-17-2018, 10:34 AM	#8
Whitespeed Drives: 2018 1SS 1LE & 1973 Datsun 240Z Join Date: Sep 2015 Location: Ontario Posts: 574	Snug up your bleeder screws a little more. Or back off and retighten to reseat the screw. Under heavy/repeated braking a small amount is liking seeping past. It won't necessarily be enough to see a noticeable change in the reservoir fluid level, but it can still make a mess. I use a pipe cleaner to clean out the nipples after bleeding. As for your oil level, I don't want to cause alarm, but after 3 track days and 2500 miles, my oil level has not dropped at all.

07-17-2018, 01:04 PM	#12
tmalaquin Drives: Blue ss 1le 18 Join Date: Apr 2018 Location: NoCal Posts: 67	Thanks for the recommendation y'all, I will clean them and tighten them to 20 Nm this weekend, and check on the next OTD... I just noticed that I lost one inboard cap so it must have been weeping there as well. As far as the oil consumption, Despite Whitespeed's statement I am hoping it's normal process to have oil consumption during OTD when weather is hot (90F), and you push hard on the throttle. What is a normal oil consumption during OTD / HPDE? (engine never overheated, 3/4 of oil temp gauge)

07-17-2018, 02:09 PM	#14
tmalaquin Drives: Blue ss 1le 18 Join Date: Apr 2018 Location: NoCal Posts: 67	[QUOTE=Alpha1BC;10252952]I'll typically lose that much oil over the course of a season, but not in one session. I'd not personally be concerned at this point, just based on tolerances some engines will burn more than others. At a minimum I recommend keeping an eye on your oil level more than usual to make sure it doesn't get any worse, keep an eye on your coolant reservoir (the lower one) to make sure it's not turning brown, and keep an eye on your oil during changes to make sure it's not milky or otherwise discolored to make sure you're not mixing oil and coolant somewhere. An extra layer of safety could be to do an oil analysis through Blackstone labs or something like that to give you a little more information.[/QUOTE Thanks ALPH1BC To clarify the volume went from max to nominal on the oil height gauge, during 1h20 total track session at M1 concourse. Oil is valvoline synpower MST 5W40. I will check all the item listed above on a regular basis and potentially do an oil analysis Cheers, T

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