The effectiveness of the braking system is the foundation of safe driving. Nissan Almera Classic. It is the brake master cylinder (MBC) and the wheel cylinders that are responsible for converting pedal force into hydraulic pressure that presses the pads against the discs.
Over time, the rubber cuffs inside these units become tanned, begin to leak liquid, or jam. If you notice a soft pedal, leaking brake fluid at the pedal or uneven braking, replacing the brake cylinder becomes an inevitable procedure. Ignoring these symptoms can lead to complete brake failure at a critical moment.
Diagnosis of faults and selection of spare parts
Before proceeding with disassembly, it is necessary to determine exactly which unit requires replacement. Most often, owners encounter problems with the master cylinder, located in the engine compartment, or the working cylinders on the wheels, which are hidden behind the brake discs.
The main symptom of a malfunction master cylinder is a drop in the fluid level in the tank without visible signs of leaks on the wheels, as well as a failing brake pedal. In the case of front or rear mechanisms, symptoms include fluid leakage from under the caliper boot or drum, as well as spontaneous braking of one of the wheels.
When choosing a new spare part, it is important to consider that for Nissan Almera Classic There are different modifications of the brake system depending on the year of manufacture and configuration. Low-quality analogues can quickly fail due to mismatches in piston sizes or quality of o-rings.
- 🔍 Visually inspect the rubber cuffs for cracks or swelling.
- 💧 Check the tightness of all brake line connections.
- 🛠️ Use only certified DOT-4 brake fluids.
Saving on the braking system is unacceptable, since the lives of the driver and passengers directly depend on it. It’s better to overpay for an original unit or a proven brand than to face a system failure on the highway.
⚠️ Attention! Using incompatible brake fluid can cause the rubber seals to swell and cause immediate brake failure.
Necessary tools and workplace preparation
To carry out replacement work, you will need a standard set of automotive tools, but there are also specific devices that will greatly simplify the task. You will need a set of sockets and spanners, including size 10 mm, 12 mm and 17 mm, as well as a special key for bleeder fittings.
Also, be sure to prepare a container to drain the old brake fluid, as it is toxic and can damage the paintwork of the body if it gets into it. Don't forget to use clean cloths and protective gloves, as working with chemicals requires caution.
If you are planning to replace the wheel cylinder on your rear drum brakes, you may need a special spring puller and a tool to remove the caliper guides. The master cylinder often requires a wrench to unscrew the tubes from the housing.
- 🔧 Set of socket heads and ratchet with extension.
- 🧴 Container for collecting used brake fluid.
- 🧽 Clean rags and rags for cleaning up spilled liquid.
- ⚙️ Special wrench for brake bleeding fittings.
☑️ Preparation for replacement
Brake master cylinder replacement process
Replacement work master cylinder begin by disconnecting the battery to prevent a short circuit when disconnecting the fluid level sensor. Next, you need to drain all the brake fluid from the system using a syringe or bulb so that it does not get on the engine parts during dismantling.
Disconnect the electrical connector of the fluid level sensor, and then carefully unscrew the nuts securing the brake pipes. Be very careful as old tubes can be brittle and easily break if too much force is applied. If the tubes are damaged, they must be replaced with new ones.
After disconnecting the tubes, unscrew the nuts securing the cylinder itself to the vacuum brake booster. Remove the assembly and clean the mating surface on the amplifier from dirt and remnants of the old gasket. Install a new cylinder, having first lubricated the O-ring with special lubricant.
Attach the new unit, tighten the fastening nuts and connect the brake pipes. It is important not to overtighten the tube nuts so as not to strip the threads, but also not to leave them too loose. Connect the electrical connector of the sensor and return the battery terminal to its place.
⚠️ Attention! It is strictly forbidden to use old brake pipes if they show signs of corrosion or mechanical damage.
Before unscrewing the tubes, mark their location with a marker so that during assembly you do not confuse the connection points if they differ in length or bend.
Replacing working cylinders on front and rear wheels
Replacing the wheel cylinders on the front wheels, which are usually built into the calipers, requires removing the wheel and removing the brake caliper. Unscrew the caliper guides, carefully remove it without damaging the brake hose, and secure it with wire to the suspension spring.
Next, remove the brake pads and unscrew the bleeder fitting or the cylinder body itself, if the design provides for its replacement separately. Install the new cylinder, making sure the piston is completely recessed into the housing. This can be done using a clamp or a special puller.
For rear wheels with drum brakes the process is more labor intensive. It is necessary to remove the brake drum, which often sticks, and dismantle the springs and handbrake levers. Only after this is access to the working cylinder, which is secured with two bolts to the rear beam.
- 🛑 Unscrew the caliper guides and remove it from the bracket.
- 🔩 Remove the old working cylinder, first draining the liquid.
- 🔄 Install the new unit and make sure there are no distortions.
- 🧼 Clean the seat from rust before installation.
How to unscrew a stuck drum?
Use a special puller or gently tap the inside of the hub through a wooden spacer with a hammer to avoid damaging the parts.
- Front discs + Rear drums
- All wheels are rims
- All wheels are drums
- I don't know
Bleeding the brake system and checking leaks
After installing new components, it is critical to properly bleed the brake system. Air trapped in the lines makes the pedal “wobbly” and reduces braking efficiency. Start the procedure with the wheel furthest from the master cylinder, that is, the rear right one.
Fill the reservoir with new brake fluid and keep an eye on the level while bleeding to prevent air from entering the master cylinder. Have a helper press the brake pedal while you loosen the bleeder valve, releasing the fluid/air mixture.
Repeat the process until a clean, bubble-free stream of liquid comes out of the hose. Move to the next wheel in order: rear left, front right, front left. After bleeding is complete, check that the pedal is stiff and there are no leaks in all connections.
If the pedal remains soft, there may be air remaining in the system or there may be a problem with the master cylinder. In this case, the procedure will have to be repeated, possibly using a vacuum pump to more effectively remove air pockets.
- 🚗 Start pumping from the wheel farthest from the GTZ.
- 🛢️ Constantly monitor the liquid level in the tank.
- 💨 Check that there are no air bubbles in the exiting stream.
- 🛑 Check the tightness of all connections after completion.
| Work stage | Tool | Important Note |
|---|---|---|
| Draining liquid | Syringe, container | Do not allow it to get on the body |
| Unscrewing the tubes | Key for 10, 12 | Act smoothly, without jerking |
| Cylinder installation | Ratchet, dynamometer | Observe tightening torque |
| Bleeding the system | Hose, wrench 8, 10 | Monitor the level in the tank |
⚠️ Attention! Brake fluid is hygroscopic and absorbs moisture from the air. Use only liquid from a closed container; do not store an open container for a long time.
High-quality bleeding of the system is 50% of success in restoring brake efficiency after replacing cylinders.
Common mistakes and advice from professionals
One of the common mistakes newbies make is trying to replace only one slave cylinder on an axle. This leads to uneven braking and the car skidding when the pedal is pressed sharply. Professionals strongly recommend changing cylinders on the same axis in pairs.
Another common problem is neglecting the condition of brake lines and hoses. If rubber hoses have microcracks or swelling, they may burst under pressure during emergency braking. Be sure to inspect them every time you replace cylinders.
Don't forget about cleanliness. Even a small amount of dust or dirt getting inside the brake cylinder can cause it to jam. Work in a clean room and close all openings in the system with plugs immediately after disconnecting the tubes.
It is also important to properly dispose of used fluid and old parts. Brake fluid is a toxic waste and should not be discharged down the drain or onto the ground. Take it to a special collection point for chemical waste.
- 🔄 Change working cylinders on one axle only in pairs.
- 🔍 Inspect all hoses and tubes for defects.
- 🧹 Work in a clean environment, excluding dirt.
- ♻️ Properly dispose of waste fluid and parts.
Why does the pedal fail?
This may indicate the presence of air in the system, a malfunction of the cuffs of the new cylinder, or problems with the vacuum booster.
Final Maintenance Recommendations
After successful replacement and bleeding, a test drive should be carried out in a safe place. Accelerate to a low speed and press the pedal smoothly and then sharply to evaluate the effectiveness of braking and the absence of extraneous sounds.
Carefully monitor the behavior of the car in the first days of operation. If the pedal becomes soft again or a squeak appears, you must immediately return to the diagnosis. There may be air left somewhere or an error was made during assembly.
Regularly checking the brake fluid level and cylinder condition will help avoid serious damage in the future. Change the fluid in the system every 2-3 years, even if visually it seems clean, as its properties deteriorate over time.
Compliance with all technical standards and the use of high-quality spare parts will ensure long and reliable operation of your brake system. Nissan Almera Classic. Remember that road safety depends not only on the skill of the driver, but also on the serviceability of the car.
Regular preventative maintenance and timely replacement of worn components is the key to your safety and the longevity of your car.
How often should brake fluid be changed?
It is recommended to change the brake fluid every 2 years or 40,000 kilometers, as it absorbs moisture over time and loses its properties.
Is it possible to mix different brands of brake fluid?
It is strictly forbidden to mix liquids of different brands and types (for example, DOT-3 and DOT-4). This can cause a chemical reaction, destroying the rubber seals and causing brake failure.
What to do if the brake pedal remains soft after bleeding?
Most likely there is air left in the system. Try bleeding the system again, paying special attention to the master cylinder. Also check the tightness of all connections and the condition of the new cylinders.
Do I need to change brake pads when replacing cylinders?
If the wear of the pads approaches the limit value (less than 2-3 mm), they should be replaced. This is also a good opportunity to check the condition of the brake rotors and caliper guides.