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Master Cylinder Repair Kit

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Not a brake mechanic or a clutch expert? Don't worry. We'll help you figure out troubles with the master cylinder and even give you solutions for rebuilding a broken one using a brake master cylinder repair kit. Here are some troubleshooting tips:

How to find out if you have a bad brake master cylinder

  • Step on the brake pedal a couple of times to check the pressure. If the brake pedal is too soft, this indicates lack of pressure, which can be caused by a faulty cylinder.
  • Check the brake fluid level. If there's no evidence of leaks in the reservoir, lids, or lines, and there's enough brake fluid in the system, braking trouble may be brought about by a defective cylinder.
  • Inspect the brake lines for signs of leaks, rust, or corrosion. Leakage through the O-ring can be hard to trace. To check for any evidence of leak, wipe a clean rag along the lines. If there's no fluid on the rag, then the problem may lie with the cylinder.
  • Examine the cylinder grommets. Rubber grommets seal the plastic reservoir of brake fluid to the master cylinder's metal part. Exposed to fluid pressure and brake pedal movement, these grommets may eventually tear or crack, causing fluid leaks.
  • By checking other brake components, you can pinpoint the real cause of the brake fluid leaks, isolate the braking problem to a faulty cylinder, and determine whether you will need a master cylinder repair kit or any replacement part.

    Signs of a broken clutch master cylinder

    • Soft pedal. When a clutch pedal has lost its usual resistance when you step on it, this could mean that there are leaks in the master cylinder. The leaks may be coming from the broken seals.
    • Difficult shifting. Shifting gears would be difficult if you can't press on the clutch pedal easily. This could be a symptom of a failing cylinder.
    • Sinking clutch pedal. The hydraulics of the clutch is probably messed up if the clutch pedal sinks to the floor. A pedal that gets stuck to the floor can be fixed by doing a cylinder repair using the right master cylinder repair kit.
    • Low transmission fluid level. If the transmission fluid supply is depleting fast, this could be a leakage problem. The cylinder or any other parts of the transmission system may have cracks or holes.
    • Noise when clutch pedal is pressed down. That loud noise when you press down the clutch could be a sign of a leaking cylinder. The faulty cylinder may fail to hold the release fork as you hold down the clutch pedal.
    • Oily cylinder. You might find oil at the bottom of the cylinder if this is leaking. To be sure, visually inspect this component right under the hood.

    To check for a faulty clutch cylinder, you can ask someone to hold down the clutch as you go check for the rise of transmission fluid in the reservoir. As the clutch is released, see if the fluid will still rise. If so, then you're dealing with a bad cylinder.

    Using a master cylinder repair kit to rebuild the cylinder

    If all symptoms and results point to a faulty master cylinder, you have to get on your toes and fix this ailing part to restore the car's braking power and to enjoy smooth gear shifting. You won't always have to replace the cylinder. You can rebuild the unit using the right repair kit.

    The master cylinder repair kit should:

    • Match the cylinder of the brake system or clutch assembly (check the part number and other product details to be sure that it fits the vehicle and its engine)
    • Come complete with all the hardware needed for rebuilding the unit (check if the kit comes with a reservoir and other important attachments or components)
    • Have a manufacturer warranty for your safety (check if the master cylinder repair kit comes with instructions or fitment labels)