Tip & How-To about 1991 BMW M5

Brake fluid disappearing

If brake fluid is disappearing from the reservoir and you can’t find a leak, check the pedal bucket. A leaking clutch master cylinder will fill it up with fluid, with no exterior leaks. And it holds nearly a pint of fluid!

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Why is my clutch feel like there is air in the line it seems to have alot of play.


Air in the hydraulic clutch release System. The system consists of the clutch master cylinder, line, hose and clutch slave cylinder. Check the level at the clutch master cylinder. The fill reservoir is along the firewall on drivers side with a black cap. It uses DOT 3 brake fluid. Add fluid if low and pump pedal. If low you have a leak. If full you have a master cylinder internal seal bad so you have to have the master cylinder for the clutch replaced.

Jul 24, 2014 | 1996 Pontiac Sunfire

1 Answer

clutch master cylinder low on fluid is it a sign off a bigger problem???


Only if it has a leak somewhere. Not that many places to check. Sometimes the master will leak, and you will have brake fluid below the clutch pedal.
A single steel line runs from master to the slave cylinder, down on the transmission bell housing. Check the line and the slave cylinder for leaks. If the slave is leaking, probably need a new one. And same for the master cylinder.
Fill the reservoir and check clutch operation. If any air got in the line to the slave, you will have to bleed the slave at the bleeder valve there. They are bled just like brakes, using the clutch pedal.

Dec 10, 2013 | 1996 GMC Sonoma

1 Answer

bleeding the clutch after installing/96 bronco xlt


Clutch Master Cylinder ABCDEFGHIJKLMNOPQRSTUVWXYZ Inspect/Replace The clutch master cylinder is located next to the brake master cylinder. A slave cylinder is attached to the release lever at the clutch. The two cylinders are attached hydraulically by tubing and hose.
f62-17.gif A hydraulically operated clutch. To Remove:
  • Take off the reservoir cover and remove the fluid from the reservoir.
  • Disconnect any wires connected to the reservoir or master cylinder body.
  • Disconnect the tubes.
  • Remove the nuts or bolts attaching the master cylinder to the vehicle.
  • Slide the master cylinder off. If it will move only a short distance but no farther, replace one of the nuts or bolts (finger tight) to support the master cylinder and then disconnect the pushrod from the pedal. After disconnecting the clip or pin and clip holding the pushrod to the pedal, try to remove the master cylinder again.
To Replace:
  • When installing a new master cylinder, it is a good practice to flush the cylinder with clean brake fluid. This is done to remove any debris that might be left over from the manufacturing process or chemical coatings that were used to protect the cylinder from corrosion. To flush a master cylinder, simply fill the reservoirs and the cylinder bores about one-third full with clean brake fluid, install the reservoir cover, plug the line ports, shake the cylinder to work the fluid all around, and drain out all the fluid.
  • Bench bleed the cylinder.
  • If the old master cylinder used a boot or hub seal, a new one should be installed as the master cylinder is being replaced.
  • Place the master cylinder in position, replace the mounting bolts or nuts, and tighten them to the correct torque.
  • Reconnect the pushrod to the pedal as necessary.
  • Remove the plugs or bleeder tubes from the outlet port as you connect the line. Do not tighten the line yet. Place a shop cloth under the line fitting to catch any fluid that may leak out.
  • Fill the reservoir about three-fourths full with brake fluid.
  • Have an assistant slowly push the pedal as you observe the connections a the outlet port. They will probably be leaking some fluid with air bubbles. Continue the pedal strokes until only fluid with no air bubbles leaves the connection.
  • At this point, tighten the connection with the pedal is being pushed downward.
  • Fill the reservoir to the correct level and replace the cover.
  • Reconnect any wires that were disconnected.
  • Check the brake pedal free travel and adjust it if necessary. There should be 1/16 to 1/8 in. (1.6 to 3.1 mm) of free travel before the pushrod engages the piston in the master cylinder

May 08, 2012 | Ford Cars & Trucks

1 Answer

Clutch pedal drops to the floor with no real effort. How do I check the master cylinder?


CLUTCH AND MASTER CYLINDER SHARE THE SAME RESERVOIR YOU CHECK LEVEL IN THE MASTER CYLINDER.ADD BRAKE FLUID TO THE MAX LINE DONT OVER FILL.IF MASTER CYLINDER RESERVOIR IS EMPTY.CHECK FOR FLUID LEAKS AT CLUTCH LINES AND CONNECTIONS AT CLUTCH RELEASE CYLINDER AND CHECK BRAKE LINES - CALIPERS - WHEEL CYLINDERS AND BRAKE BOOSTER.FIX LEAKS AND BLEED BRAKE AND CLUTCH SYSTEM.

Jul 25, 2010 | Cars & Trucks

2 Answers

My clutch pedal is stuck to the floor??


It is most likely a hydraulic clutch, and it is most likely leaking at the clutch slave cylinder. Check the clutch master cylinder for fluid, it should be a small master cylinder looking thing with a fill cap next to the brake master cylinder and booster unit. If it is empty fill it with the same dot 3 brake fluid that you use for your brake master cylinder, and make sure that you are pouring the fluid into the clutch master cylinder reservoir and not the rubber seal that should be under the fill cap. After filling the clutch master cylinder up with fluid, then try and pump up the clutch pedal. It might take a while to pump up hydraulic pressure, and you might also have to work the pedal a few times by hand at first.

Also, you might have to bleed the clutch at the slave cylinder if it will not build up enough pressure to release the clutch.

Apr 28, 2010 | 1988 Mazda RX-7

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