Car Wheel cylinder

Wheel brake cylinder is an important part of the hydraulic brake system. Inside it there is a feed cylinder. It transports the brake fluid into the feed cylinder, which is on the disk brake bracket. In cars there are used only two-space brake cylinders with two pistons. Due to this fact the brake system is operating even if one cylinder fails.

Sooner or later in the wheel brake cylinder all the substances that have no any relation to the brake system sink. First of all we speak about water and rust. They form a mix that has extremely unpleasant effects. Small rust particles act as emery and are constantly moving with pistons inside the wheel brake cylinder. It is very important to follow replacement limits indicated by the manufacturer. If there is brake fluid leakage, the gasket is worn out. When disassembling the brake cylinder, you need carefully to examine it. If it is worn out, it is required to install a new one. Costly repair of the cylinder is justified only if the parts are not available or the price is too high.

Since the wheel brake cylinder is a part of the brake system, only a mechanic with relevant knowledge and experience should replace it. It would be better to address to a repair shop if you have problems with the brake cylinder. On our website you will find baggage/cargo compartment, cooling hoses, clutch discs, fuel filters, crankshaft bearing insert, filters and many other parts necessary for your car. It is more convenient to visit our online shop then a specialty shop.

Wheel brake cylinder failures

• cylinder bearing surface defects;
• cracks on the pistons;
• piston sealing cups wear;
• piston sealing cups damage;
• slackening of the piston return springs;
• piston jam.

Signs of wheel brake cylinder failures

• free pedal travel;
• metal corrosion;
• increase of the brake path;
• frequent car skids when passing the turns or braking;
• increase of pedal stiffness;
• sinking of  brake pedal;
• hydraulic fluid leakage .

Causes of wheel brake cylinder failures

• compensation port obstruction;
• lack of hydraulic fluid;
• mounting of low-quality parts;
• use of faulty consumables;
• water or admixtures in the hydraulic fluid;
• wear of components;
• non-conforming hydraulic fluid usage;
• untimely service of the brake system elements;
• disregard of vehicle operation rules;
• aggressive driving style;
• untimely change of hydraulic fluid.

Diagnostics

You should carry out the inspection of a wheel brake cylinder every month. In some cases visual inspection will be sufficient. However make sure if there are any signs detecting failure. For example, it may be change of the pedal travel. Diagnose the braking system every 30000 operational  kilometers at service station.

Repair and replacement of wheel brake cylinder

This part can only be repaired if there are cracks or other damages of sealing cup and covers. We will remind that replacement of all rubber components of this unit should be performed at each inspection. You should do the following:

• drain hydraulic fluid;
• disconnect the cylinder;
• carry out its cleaning.

If failure of valves and cylinder bearing surface was detected, it is necessary to immediately make replacement of the whole unit.

We will remind that it is rather simple operation to dismantle a wheel brake cylinder. So, do the following:

• park the car on the first gear;
• secure the front wheels;
• dismantle a wheel;
• clear the cylinder and a brake tube off dirt;
• unscrew the nut that fixes the tube and cylinder;
• disconnect a brake hose from the cylinder;
• blank off a hose hole (for example, by the cap from the bleeding valve);
• turn off fixation bolts. When doing that, hold the cylinder;
• remove the cylinder from a brake back plate.

Important! Don't forget to bleed the braking system upon the termination of replacement.