clutch fluid (1 Viewer)

[robstar]

Hi - I replaced the clutch master and slave cylinders on my bj44;
flushed and replaced clutch fluid three times. After a while (few months), the
fluid in the master cylinder gets dark. Is this an indication that I should
replace the steel clutch line(s) also?

Thanks.

 

[DougAustinTx]

Well, it means that your lines are either dirty or rusty. If you clean the system out with brake cleaner squirted through the lines until it comes out clean, then remove and disassemble the master and slave to clean the DOT 3 fluid out, and replace it with Dot 5 silicone fluid, you probably won't have the discoloration any more. My clutch fluid is 5 years old and still looks nice and purple like it did when I put it in.

 

[davegonz]

What is this purple nurple fluid you mention? What brand are you using?

 

[robstar]

Thanks for suggesting the dot 5 silicone fluid. Sounds like a good idea.
Did changing to dot 5 cause any damage to the rubber seals? How did you clean
the parts (master, slave, steel line) that were coated with dot 3 fluid?
What is the recommended fluid change cycle for dot 5 fluid?

 

[DougAustinTx]

Dot 5 silicone fluid has no recommended change period. It doesn't absorb moisture so it is good indefinitely as far as I know. I use brake cleaner to clean all the DOT 3 out of everything before adding the DOT5....... otherwise any remaining DOT3 will sink to the lowest point and the moisture in it will cause a rust pocket. Not all DOT 5 is silicone, you have to check to make sure it says silicone on the label. I have never experienced any degradation of rubber that was in contact with the silicone, and I have used it in lots of vehicles. In answer to the question by davegonz, almost all DOT 5 silicone that is sold is colored with a purple dye to differentiate it from the other DOT fluids.

 

[robstar]

Great, I'll go for Dot 5 silicone.
Thanks.

 

[davegonz]

Might have to try that.

 

[emac]

If you are switching to silicone fluid you should make sure all the old fluid is removed as pockets of of old fluid will still gather moisture.

It is also worth noting that silicone fluid is not recommended for racing, so no heavy track use

 

[Jetlander]

If you are switching to silicone fluid you should make sure all the old fluid is removed as pockets of of old fluid will still gather moisture.

It is also worth noting that silicone fluid is not recommended for racing, so no heavy track use

Glad you added that tidbit of info at the end. I was about to take the cruiser to the drag strip and make a few runs.