Ranger Clutch Fluid Change procedure?

Originally Posted by Fountainhead

Hi All,
Open the Clutch Master Cylinder reservoir lid and have someone press the clutch in and out and you will see the fluid of the MC reservoir moving as you cycle the clutch. Think about it, where will the volume of fluid pushed into the CSC return to after actuation? The CSC rides against the Clutch fingers and CSC is normally depressed about 50% position. When the clutch pedal is pressed the CSC fully extends and presses the clutch fingers in about ~0.5 to 0.75 in. When the clutch pedal is pressed in and released, the CSC returns to 50% position. The volume of liquid used to increase the CSC position has nowhere else to go but back into the master cylinder. CSC fluid is constantly changing location from the CSC back to the Clutch master cylinder reservoir.

Brakes only travel a fraction of an inch to press the calipers and the volume of liquid moving is far far less, traveling 5x the distance of the Clutch fluid so there is really no noticeable change/fluid volume change in the brake reservoir.

So in short, the Clutch fluid does move around and is not trapped entirely in the CSC.
Brake fluid is trapped at the Caliper cylinder and cannot move back to the Brake master cylinder.

yes I still regularly change my clutch fluid and for 5 years have used DOT 3/4 Valvoline and so far no problems. It's clean as a whistle. I never let it get even slightly dirty.
I usually empty the master, fill it up, pump the pedal about 12 times then empty the master and fill it back up again. I suppose one day I'll bleed the CSC from the bottom but I will only do so to find out if it has foreign bodies *clutch dust* in the bottom. If the video guy had pumped the clutch about 12 times after the initial fluid removal/addition you would have seen the dirty fluid returning to the master reservoir after a few pumps. Honestly mine has never been dirty enough but to barely see the fluid is contaminated, so I doubt mine is dirty down at the CSC.
If it had been black and chunky I would have bled from the bottom. I may still bleed from bottom, and report back here but I expect to see clear fluid.

Originally Posted by Fountainhead

You're welcome!

Well the fluid has no where to go after pedal release but back into the reservoir. Since fluid does not compress there is no "squeezing" the fluid, it's a solid under pressure. After releasing the pedal the fluid from the bellows/CSC cylinder must go somewhere and there is no room anywhere in the hydraulics *(hose, CSC) but in the reservoir. Just experiment and see for yourself.
It wouldn't hurt to bleed the system just for your peace of mind. Be careful to not release the clutch pedal until the valve/bleed screw is closed. And be gentle when pressing the pedal as there won't be any fluid/cylinder resistance to limit the pedal travel and you could damage the O-rings in the master cylinder. My fluid has always been crystal clear so I've never had to pump "30 times" usually only about 12. Just for my peace of mind, lol. Peace of mind is worth a LOT. Plus I'm a short shifter, non dragster, non launcher so my CSC will probably never get even slightly dirty.

Good Luck Sinister, and welcome to the forum!

Originally Posted by nis350

1. when you release the clutch pedal, the csc would retract to its original position and pushing the fluid back to the same spot in the clutch line. The operation is quite simple, when you press on the clutch pedal, the cmc pushes the fluid downward to the csc, and you release the clutch pedal, the fluid goes back to the same spot on the clutch line. So the fluid just goes back and forth in the clutch line pretty much on the same spot as there is no way for it to circulate anywhere else.

2. during the bleeding process, you press the clutch pedal down first, then open the bleed valve. so there is pressure/resistance as normal. also, the cmc always does full stroke when you press down the clutch pedal, so there is no groove to damage the seals like an old brake master cylinder.