New clutch fluid reservoir installed.

[Robert M]

You could disconnect the hydraulic line at the transmission end, drain out all the fluid and flush the system. Then reconnect the line and fill and bleed. Since the slave cylinder will be in the retracted position, there shouldn't be much fluid inside it or the line.
Clutch System Bleeding - 2.pdf

It looks like McLeod makes a bleeder that can be attached to the end of the line at the transmission which allows the system to be bled from the reservoir to the bell housing, it is about $60.

https://www.jegs.com/i/McLeod/673/1...MI0cajsMHg2gIVBQeGCh2jLwG7EAQYAiABEgJcWvD_BwE

Unless the system is bled, old contaminated fluid will continue to make its way up into the new fluid in the reservoir, that is why I was thinking t would be nice to get rid of all (or most) of the old fluid below the clutch master. The McLeod bleeder kit for the 2005-current Mustang appears to be the fix for that. <<I did not know such a kit was available until I did some searching this afternoon.



R

 

[Robert M]

Here it is with a more detailed application description.....

https://jmautosports.com/mcleod-rac...ulic-clutch-bleeder-kit/139250/i-2296511.aspx



R

 

[99VERT]

 

[99VERT]

Less than 200 miles of driving and the fluid is black!

 

[Snoopy49]

8600 miles and over 5 years. The darker appearing fluid is a byproduct of the shadow cast by the cameras flash.
This is the brake/clutch reservoir.

 

[99VERT]

Not in my case. Sucked all the fluid out tonight and refilled with fresh.

 

[Snoopy49]

What's causing it to turn black?

 

[99VERT]

My car is coming up on 19,000 miles. I have a feeling that it’s a lot of the older fluid that’s mixing with the new or fluid. My plan is to continue to swap out all the fluid I can get to and try to get it cleaner.

 

[Robert M]

What's causing it to turn black?

I would guess that it is deterioration of the system from the inside from contaminated fluid.

This is the same fluid as the brake system (or it was before the reservoir separation) and that fluid absorbs moisture from the air. The plastic lines are not going to deteriorate from the moisture (water) in the system, but the inside of the clutch master bore and the slave cylinder will, and discoloration of the fluid is the resulting indicator.

Unless the system is emptied at the bottom, it will be very hard to get the system fully flushed with fresh clean fluid.

I also have another idea..........Silicone brake fluid does not absorb moisture and is the recommendation for brake systems that can use it, unfortunately it is not recommended for an ABS system, but if the clutch system is separated from the ABS brake system, I wonder if Silicone fluid could be installed after a full empty of the system, it would greatly improve the longevity of the system.



R

 

[Snoopy49]

I was thinking that the seals in the master cylinder may be deteriorating, that would explain the black color. What brake fluid are you using?

 

[99VERT]

Ford Dot 3

 

[merkyworks]

I didn't bleed my system but wanted to try and get as much of the old fluid out, for 5-7 days every evening when I got home from work I would use a syringe to suck out the old fluid and put fresh fluid back in. Figured eventually it would cycle the fresh fluid down to the slave cylinder.

 

[Robert M]

I didn't bleed my system but wanted to try and get as much of the old fluid out, for 5-7 days every evening when I got home from work I would use a syringe to suck out the old fluid and put fresh fluid back in. Figured eventually it would cycle the fresh fluid down to the slave cylinder.

Most likely any heavier contaminates in the system will stay toward the bottom of the system.


R

 

[Robert M]

I was thinking that the seals in the master cylinder may be deteriorating, that would explain the black color. What brake fluid are you using?

If the seals are deteriorating to the point of discoloring the system fluid from top to bottom, that is not good either. I am going to have to look at the fluid I used. I added the Baer Extreme rear brake upgrade and flush my complete brake system at that time, that would be the fluid that has made its way into the clutch system currently, I don't think it was DOT 3, I am thinking DOT 5.5? I will have to look and report back.

>>>>I used DOT 5.1 in my system when I did the rear brake upgrade. If I add the Mcleod bleeder down at my bell housing, and keep my fluid feed in its current brake reservoir, it will feed that same DOT 5.1 to the clutch system and at that point, if the clutch system has the ability to be bled at the bell housing level for regular maint., all should be well.


R

 

[M91196]

What's causing it to turn black?

FWIW In one of the old threads here or TMO it was suggested that the clutch dust is fine enough and that a small amount can get past the TOB seals and cause the contamination seen.

I added the reservoir in 2014 at 1000 miles on TP GT but have only accumulated 7500, it’s still clean, but such low miles so not much of a test.

 

[Robert M]

FWIW In one of the old threads here or TMO it was suggested that the clutch dust is fine enough and that a small amount can get past the TOB seals and cause the contamination seen.

I added the reservoir in 2014 at 1000 miles on TP GT but have only accumulated 7500, it’s still clean, but such low miles so not much of a test.

If it is clutch dust getting into the hydraulic system, I am surprised that there are not more TOB failures, especially on the earlier cars with a CF disc clutch. I would guess the CF particles would be as bad as ultra fine sand in the system and the seals (and bores) would quickly be compromised with such an abrasive between them?

But I am still puzzled by "Black" also. I flushed my 2008 brake system at 600 original miles when I did the rear upgrade, there was Brown already in that fluid, but Black in either of these systems is a ?.



R

 

[10GT500]

Has anyone used a remote reservoir with a braided line? I like the shelby kit, and would like to get a braided line, but was wondering if the braided lines sold for these cars are long enough and have the right fitting for the reservoir.

 

[Snoopy49]

The braided line goes from the master to the slave. If they supply a braided line for the reservoir, it would still have to slip over the nipple on the reservoir. The reservoir line goes from the reservoir to the supply side of the master.

 

[Robert M]

Shown below is the FRPP clutch line upgrade with the McLeod clutch system hydraulic bleeder valve for the 2005-2014 Mustang and Shelby GT500.

R

 

[Catmonkey]

Unless the system is emptied at the bottom, it will be very hard to get the system fully flushed with fresh clean fluid.

If that were true his fluid wouldn't be discoloring. Anytime the clutch pedal is depressed, fluid is pumped into the TOB and upon release that fluid is displaced back into the reservoir. I'd just siphon and replace the fluid a few times and it should be good. It's not like you're heating up fluid like you would in the braking system.