dirty clutch fluid

[garlicbreadman]

car is 2001 acura integra.

recently replaced with:
exedy clutch master cylinder
exedy clutch slave cylinder
russell stainless steel clutch line
honda oem hose connecting reservoir to clutch master cylinder
supertech blue bottle brake fluid

car runs fantastic, but im having a problem with dirty clutch fluid. my reservoir is black again after about 2k miles of bleeding the lines. Anyone know what is causing the fluid go to black? What other component can be causing this? I had this problem before i replaced all these things. i thought the problem would be fixed after replacing the clutch master and slave cylinder since they were slightly leaking.
looks like this:

 

[Boomer]

This seems reminiscent of the blackening of the PS fluid I have always seen in new GM cars. Replace the fluid with an aftermarket one and it does not get black. I always suspected that it was the fluid slowly attacking the rubber hoses in the PS system and it sounds like you have a rubber hose in yours. You may also have exposed rubber somewhere else as well.

Since almost all DOT 3/4 brake fluid is a type of polyethylene glycl, I don't know that changing brands will help but it might be worth a try.

 

[Quest]

some extremely fine rubber debris causing the darkening of your brake clutch reservoir fluid.

This is normal for (a) the rubber cup inside the master cylinder piston is black in colour, and rubbing on the clutch master cylinder wall (honed with cross-hatching pattern BTW) and (b) over time, it will become dark ...

So long as your master cylinder piston cup doesn't leak and has good sealing, I wouldn't bother with changing the fluid so frequently (I change mine every 2 ~ 3yrs).

Q.

 

[SLCraig]

If there are no problems and the fluid is 2K old, I would just leave it alone...
I never even check mine, I am sure it looks the same.

 

[mechtech2]

Flush it out. Maybe initial break in particles from the rubber.

 

[ltslimjim]

^Thinking the same thing here...

btw, getting an EXEDY clutch master cylinder installed Thursday.

Hrm...wonder if this is the Honda brake fluid thing?

 

[Tegger]

Originally Posted By: garlicbreadman
my reservoir is black again after about 2k miles of bleeding the lines. Anyone know what is causing the fluid go to black?

Rubber particles from the master cylinder seals. Your new master cylinder will wear out a lot faster than the original did.

Either the rubber is of inferior quality, or the MC bore-surface is rougher than it should be.

Welcome to aftermarket parts.

 

[garlicbreadman]

Originally Posted By: Tegger
Originally Posted By: garlicbreadman
my reservoir is black again after about 2k miles of bleeding the lines. Anyone know what is causing the fluid go to black?

Rubber particles from the master cylinder seals. Your new master cylinder will wear out a lot faster than the original did.

Either the rubber is of inferior quality, or the MC bore-surface is rougher than it should be.

Welcome to aftermarket parts.


Oem is too expensive for some parts, i read good reviews these exedy replacement parts so i bought it. it feels like oem, but lets see how long it will last. If i get a 5+ years out of this, i'll be happy.
Originally Posted By: ltslimjim
^Thinking the same thing here...

btw, getting an EXEDY clutch master cylinder installed Thursday.

Hrm...wonder if this is the Honda brake fluid thing?

this exedy replacement is great so far. only cost me like 40 bucks shipped for both off ebay! make sure you're not over paying for it from a shop.
Originally Posted By: mechtech2
Flush it out. Maybe initial break in particles from the rubber.

i too think its from break in of new parts. i'll leave it for a few more thousand miles and flush it entirely.

 

[ltslimjim]

^I got the replacement master cylinder for mine on Rock Auto for about $25 shipping, IIRC. The slave was good when the shop replaced the clutch this December, but noted the already confirmed leak at the master from the clutch pedal/interior side itself. You can easily feel grime on the pedal. Yuck...no white shoes.

 

[JZiggy]

That's why I stick to OEM or Adler parts for Honda hydraulics. You can get them pretty cheap at Autohausaz.com

If you want to try to flush out your clutch system, you could take a turkey baster and remove the fluid in the MC and put in fresh. That would be alot faster than doing an actual bleed process. Just repeat a few times and see if it clears up.

 

[mechtech2]

TB cleaning is clean and easy, and will surely help [eventually].

 

[garlicbreadman]

Originally Posted By: JZiggy
That's why I stick to OEM or Adler parts for Honda hydraulics. You can get them pretty cheap at Autohausaz.com

If you want to try to flush out your clutch system, you could take a turkey baster and remove the fluid in the MC and put in fresh. That would be alot faster than doing an actual bleed process. Just repeat a few times and see if it clears up.

i have a vacuum bleeder that would replace old fluid with new in about 2 minutes.
exedy is a well known brand, they make clutch for almost every car make out there.

 

[dailydriver]

Originally Posted By: garlicbreadman
Exedy is a well known brand, they make clutch for almost every car make out there.


I never knew that, as I always thought that they were a high-end, top shelf (with prices to match!), ultra high performance clutch manufacturer ONLY.

You learn something new every day!

 

[ltslimjim]

^Yeah, I a got an 'OE' EXEDY clutch kit from them. Not as stout, from what I 'hear', as their previous OE replacements. So, it may not make 100,000 or last as long as the original, but if it gets me 100,000 for $575 with labor/parts, I'm good.

Got the replacement EXEDY master clutch cylinder in today, feel is great now.