vtidan

I remember reading a post recently about slave cylinders and black clutch fluid. The fluid in my car is quite black and I suspect it has never been renewed. (car has covered 33k miles and is a 2000) Would I feel any negative effects from this old crappy fluid? Im thinking I will just get it drained and changed by a local garage or will the slave cylinder likely be on its way out? I have not noticed any leakage. Will the clutch pedal feel any different with brand new fluid? One more question, do I need to replace it with DOT4 Brake/clutch fluid as on most vehicles these days??? cheers.

andyds2k

Mine was exactly the same at 33k miles, after draining and bleeding I felt no difference in the clutch pedal feel. However, if its black get it done. It only took me 30 mins to do.

What you really want to look out for is bits of debris in the fluid, this could be an indication that the seals are going.

Also DOT4 or 5 will be ok.

vtidan

cheers pal. I'll get it done.

nickrg3

Calling Davey!! Calling Davey!!

Should we call this Grand Theft Avatar?

AquilaEagle

How do you check it and change it?

RUSS H

I would not recommend changing to dot 5 in a six year old car used
on the road. Stick to dot 4.

Russ.

andyds2k

Why is that ?

RUSS H

Well dot 4 is mineral based and dot 5 is silicone based.

4 will absorb moisture, 5 will not.

So in dot 5 water absorbed from the air will sit in the brake
pipes seperately from the fluid, this can boil into vapour
under hard braking thus losing your brakes.

Dot 5 is the better choice if you maintain your system
often, as you would if you used the track a lot.

Its a divided subject to be honest. Myself ? Stock OEM fluid.

Russ.

andyds2k

I am assuming you me the clutch fluid.

To check it I guess if its black in colour then replace. Not sure why it actaully goes black apart from contaminates or possible boiling!!!..maybe. On the other hand it probably goes black for the same reason engine oil goes black, but I am no chemical enginner in oils.

To change it is the same as bleeding you brakes. There is a bleed nipple on the slave cylinder mounted on the side of the gearbox.
1) Jack car up on nearside, to gain access to the slave cyliner (don't forget to use axlestands).
2) Attach plastic tube of required diameter to the bleed nipple and place other end in a container ( 1litre size should be enough). Note there is a rubber dust cap over the top of the bleed nipple.
3) Undo bleed screw about quater turn (should be enough, but you may need to loosen more of no fluid comes out when clutch pedal is pressed.
4) Remove cap on master cylinder.
5) Press down on brake pedal and check for fluid entering container. If not loosen bleed nipple slightly (helps to have two people.
6) Release clutch pedal. You will probably have to pull it back up as it won't return by itself.
7) Keep pumping pedal until all the brake fluid has left the master cylinder. The reason for doing this is to enable you to clean the master cylinder before adding new fluid and mixing good with bad.
8) This step is up to the individual to do and you should use caution. Use a lint free cloth and carefully clean the inside of the master cylinder of any black residue. Ideally the master cylinder should be removed and cleaned with brake fluid, but that is a bigger job and personally an over-kill. Just be carefull not to leave or drop any debris into the master cyclinder.
9) Top up the master cylinder to MAX. You will need to keep topping it up to make sure it doesn't run dry while performing the next step.
10) Have some gently press the brake pedal and hold it down. Tighten the bleed nipple.
11) Release or pull back clutch to the upper position. Then undo bleed nipple.
12) Repeat 10) and 11) until the brake fluid going into the container is as clear as what you are putting into the master cylinder.
13) Now continue 10) and 11) until there are no air bubbles in the plastic tube. On the final press of the clutch (no air bubbles and clear fluid). Tighten bleed nipple and job done.
14) Now check the feel of the clutch by pressing a few times and check that it comes up by itself. If it doesn't you either have air still in the fluid/master cylinder has no fluid/bleed nipple is still loose and leaking fluid.

REMEMBER : when putting in new brake fluid and bleeding make sure the master cylinder doesn't run dry.Keep it topped up!!

15) Remove plastic tube. Check tightness of bleed nipple - be carefull not to overtighten as it is easy to strip the thread. Replace master cylinder cap after check clutch fluid level for one last time. Replace dust cap on the bleed nipple.

16) After a drive check the clutch fluid again. The level should not go down, if it does check for leaks at the bleed nipple. Then check after a week just to make sure (assuming you have been driving it).

CAUTION: brake/clutch fluid will strip paint so be carefull. Any clothes/rags used should be thrown away, you don't want to use to wipe something down later and old fluid disposed of at the local tip correctly.

Any comments or errors you see are appreciated.

andyds2k

Thanks, now I understand