How to change your clutch fluid:

 

Thanks for posting the video. Good guide to those who've never done this. Few comments below.

I don't know if I agree with evacuating the reservoir entirely. I know there's still the fluid in the hose between the reservoir and mc, but I think doing it this way there's a possibility to introduce air into the system. I've always evacuated mine to around the L line. With a small hose attached to the syringe, it picks up most of the dark particles at the bottom of the res.

Any particular reason you didn't mention gravity bleeding? I used this method last time with great results. Only used the helper right at the end to make sure there was good pedal pressure.

@3:23 clutch pedal completely up when pumping? I think you meant to say completely down when opening the bleeder screw¿?

 

Thanks for good questions and feedback. Here are my thoughts:

Gravity bleeding or power bleeding don't get air bubbles or old brake fluid out of the CSC. The hydraulic lines do, but nothing else. Here's why:



If you follow the hydraulic tubing you can see that the inlet and bleed outlet are connected a small distance away from the CSC. The fluid is has no reason to travel that extra distance into the CSC and then back out when doing a gravity bleed.

When we push your foot on the clutch to the floor, the CSC piston extends 8-10mm. Open the bleed nipple and the fluid squirts out because the spring pressure of the pressure plate pushes in the CSC piston. After the nipple is closed, we need to pump the pedal 5 (or more) full strokes to fill up the CSC with fresh fluid. By repeating these steps, we are pumping in new fluid.


Reservoir: The hose is quite long and I don't think any air could travel through the hose into the master cylinder. Even if it did, since we are collapsing & refilling the CSC, it would get pumped out anyways. This also allows easy cleaning of the bottom of the reservoir and remove all the black stuff.

@ 3:23 I will add a annotation clarifying "completely up" as in a full clutch pedal stroke: floor to absolute top. - Thanks!

With many things, there are different ways to do the same thing. The best way is the way that works for you.
Thank you again for your feedback, I appreciate it very much!

 

@MotorvateDIY

I see your point about gravity bleeding. I think a hybrid method is best then. Use gravity bleeding to bleed most of the line, then traditional to bleed the csc. I suppose given the volume of the system it probably isn't that significant, just easier on the helper.

About emptying the reservoir entirely, after thinking about it further, even if there was an air bubble to form, it's quite high in the system and should rise to the top.

One other comment discussed elsewhere, periodically changing the fluid in the reservoir between full bleeds to minimize fluid contamination. I just did that about 3 months after doing a full bleed. The fluid wasn't terribly dirty but there was already some black particles forming at the bottom of the reservoir.

 

Any reason why I couldn't/shouldn't use this for extracting the old fluid? I have one sitting in my garage.

 

That should work just fine.

 

Is there a preference on brake fluid? dot4?

 

Not really... but since the slave cylinder is inside the transmission, they tend to run hotter than the older external type. With that in mind, I like to use a high temp DOT4, like Motul RBF600.

 

Amazon. Yes.

 

Motul is kinda a high end fluid.....you're not going to find it at Walmart

 

I paid to have this done because I didn't have a helper.......

But, I'd slip the box end side of a 6 point wrench over that.

 

Sorry for the late reply....
Yes, one 500 ml bottle is enough and they can be purchased on amazon (as mentioned) Z1, or maybe your local motorcycle shop. That is where I got mine from.

 

^^^ Good advice...
and use a second wrench on the other half to prevent twisting the clutch tube.
Some WD-40 or your favourite penetrating oil would also be a good idea.

 

Does anyone have experience doing this with the rjm pedal? I'm having a terrible time getting this to work. The first time opening the bleeder was fine, plenty of fluid came out. Each time after that (with pumping several times) less fluid came out .I have gravity bled it about 3 times and that seems to reset this cycle. After bleeding 3-4 times almost no fluid comes out and it takes about 30 pumps of the clutch pedal to feel like pressure is back. When I loosen the bleeder to gravity bleed, it sound like air is getting sucked back in. ?.. l messed around increasing the travel of the pedal but it doesnt seem to change anything. All l can think at this point is to reinstall the original pedal and try again. I've had no issue needing to pull the pedal up after bleeding.
Well, put the oe pedal in. Now I have to pull it up every time. Waiting on a helper before I attempt bleeding again.
I don't think the rjm pedal was a factor in this. But what a PITA this was. The one time we didn't lose count, it required 47 pumps to get pressure back in the pedal. I put the rjm back in and drove it around the block last night. Top of my head don't remember all the little adjustments to be made but, it engages about half an inch from the floor. Not taking the kids out like that. Will mess with it today then probably never flush the clutch again.

 

How are you gravity bleeding it?

I just flushed/bled mine as part of 2 yr maintenance. My process is this;

1) Suction out old fluid up to the min mark - I use a small hose on the end of the medical suction device (something like this ) to get at the debris at the bottom of the reservoir. Refill then repeat until fluid in reservoir is all new.

2) Open bleeder at slave until fluid starts to come out, ~1/2 to 1 turn is enough.
3) Monitor reservoir and refill as needed. Usually 3-4 refills is plenty.

4) Snug (but not fully tighten) bleeder screw
5) Have helper slowly pump pedal 5-6 times then hold
6) Proceed with traditional bleed.
7) Do this about 4-5 times.
8) When satisfied, snug up the bleeder. DO NOT OVER TIGHTEN!!

Step #5+ is needed to replenish small amount of fluid left in the line by the slave which is not replaced by gravity bleeding.

In your case if no fluid is coming out then either there's air in the line and/or bleeder isn't open enough. Fluid doesn't gush out but does come out at a steady rate. This is probably 3rd or 4th time doing it. No issues with the above method.