Sludge in clutch reservoir

[Beer van Huet]

I have changed my clutch fluïd about 5 times and twice there was black sludge lying at the bottom
The fluid was still clear and it’s not a large amount
Does that indicate something?
Just the clutch not the brake reservoir
TIA

[WintrSol]

It tells me that the flexible clutch hose hasn't been replaced in a while, and is slowly dissolving on the inside. Or, the seals on the master cylinder are doing the same, and the debris is migrating into the reservoir.

[Beer van Huet]

That makes sense
I haven’t changed the clutch hose in 20 years
Thanks, Wintrsol

[WintrSol]

If the brake lines are the same age, it may pay to get a complete kit, and to them all. Just don't spill the fluid.

[Ricky-D]

It could be simply the gasket for the master cylinder cover.

That would be my preferred choice and that is what I would replace.

I know what migrate entails and I really doubt that is the case.

***

[CoreyP]

It could be simply the gasket for the master cylinder cover.

That would be my preferred choice and that is what I would replace.

I know what migrate entails and I really doubt that is the case.

***

Yep, just did my clutch fluid and there was black stuff in the bottom. Felt the rubber diaphragm and it was coarse turning my finger black when I rubbed it. Happened to have another rubber diaphragm for another Honda, exact size that should solve the problem. Strangely my front brake one looked brand new, think that one has been changed out.

The brakes and clutch diaphragm is supposed to be changed out every time you change the fluid, I think that is over kill but if your diaphragms are 10 plus years old I would change them out. If they are 20 I would switch them out for sure next fluid change.