Clutch breakfluid turns black????

[Vaatjie]

I did a complete inspection on my patrol and decided to do preventative maintenance on some items. This now include servicing the master and slave cylinder on the clutch. (The vehicle has only 80 000km on and is a 2006 model.) Overhauled the two cylinders and filled the system with new oil. 3 months down the line I noted that the DOT4 oil is black. Took a syringe and took out the black oil. Cleaned the reservoir. Filled with new DOT 4. Bleed the system again. Three weeks down the line and the oil is turning black again. Now my question is.
1. Can the engine oil or gasses enter this system through the vacuum assisted clutch system????
2. Bad oil.??? Tried to bleed the system with DOT5.1 oil. Could not get the system bleed, so I change to DOT4.
3. Bad o-rings from Hydra drive?????

The DOT4 oil is also dissepering slowly. Now leaks on system. Did an Orange River trip in December 2011/12 and would have seen a leak clearly on the system with all the dust.

[Herrie]

Maybe it is because the exhaust is very close to the slave cylinder and the heat is changing the color.

[Peter Connan]

I think you have bad O-rings.

Also, I would not recommend the use of dot 5 brake fluid in a Patrol. The reason I say this is that the higher the dot rating, the more resistant the brake fluid is, but also the more hygroscopic it is. In other words, it absorbs water faster, and this causes the internal surfaces of the cylinders to rust if the brake fluid is not replaced regularly.

[BABELAAS]

on a recent trip to Namibia, my clutch pedal went pap and had to be pumped to change gears. It was extremely hot ( about 40 degrees). I checked that the clutch fluid was not leaking, it looked clean and not boiling or hot. ( I had had the brake and cluth fluid replaced last year before a trip through Botswana).
To make a long story short , I had the cluch fluid and the brake fluid replaced and the problem was resolved, for the rest of the trip, the cluch was perfect. I can only assume that the clutch fluid had absorbed moisture somehow!!!

[ricster]

I want to replace my.... well my Patrols clutch fluid, as I see that the fluid is quite black.

I've never done this job before, so.....Can this be done by me alone? And how do I do it?

I thought if I can do it alone, then I would remove the bleed screw/nipple at the gearbox side and allow the fluid to drain out by gravity. Then when empty fill up the reservoir till the new fluid runs out underneath ( at the g/box side) to flush out the system a bit. Then refit the bleed screw while new clutch fluid is running out the bottom. Top up the reservoir and Bob's your auntie

BUT.... I'm probably completely wrong in my assumption.... which would make me look like the first 3 letters of the word assumption ....ha ha

[marakasmalan]

Hello Gents,

Four main possible causes:

1. Heat
2. Pollution (moisture contamination or other foreign substance)
3. Poor bleeding
4. Seals

Yes, you should see the leaks, but only if the leak is where you are expecting it. More experience members my elaborate on that aspect.

If you ask "can I do it alon/by myself" it means yes you can, but you should not. Yet. If you are in my valley call in, I may help you with the self bleeding system. Not rocket science but it help to see it once in operation.

Also, on the brakes, once you bled all four brakes bleed them again, makes a difference - learned this from the Alfa guys but it applies to any vehicle and it makes a notable difference.

You are not the first person to replace these type of seals, so find out from the others and get sound advice.

Cheers