UAZ clutch master cylinder: characteristics and description

2024 Author: Erin Ralphs | [email protected]. Last modified: 2024-02-19 11:42

Any car with a manual transmission is equipped with a mechanism such as the clutch master cylinder. UAZ "Loaf" is no exception. How is the clutch master cylinder? What is it for in the car? All this - later in our article.

Clutch Features

In this case, we are looking at a manual transmission. The car cannot constantly move in the same gear. Accordingly, to switch it, you need to disconnect the box from the engine flywheel.

To disengage the friction discs, there is a clutch slave and master cylinder. UAZ "Patriot" is also equipped with them. There are no such elements on foreign cars with automatic transmission. Thus, it briefly disconnects the motor from the transmission and, when the pedal is released, smoothly engages them. The car is already in high (or low) gear.

Hydraulic drive

Ulyanovsk production cars use a hydraulic clutch drive. This node combines several elements, namely:

• UAZ clutch master cylinder.
• Hydraulic tubes and hoses for fluid circulation.
• Expansion tank filler.
• Clutch slave cylinder.
• Return spring and pedal.

With the help of the latter, the entire complex node is controlled.

How does it work?

When the driver presses the pedal, a force is created in the system, which is transmitted through the rod to the clutch master cylinder. UAZ 469 still rides "in gear". Further, for a short period of time, the cylinder perceives these forces and transfers them to the worker.

In this case, the liquid passes through metal tubes and rubber hoses. The working cylinder is connected to the fork. When the element piston moves up, the fork is actuated and moves the release bearing. Thus, the system disconnects the motor from the transmission. This will continue until the driver releases the pedal back. You should not keep it for a long time, as the release bearing wears out a lot. Over time, he begins to buzz. Therefore, experienced drivers are advised to release the pedal if the car is standing for more than 10-15 seconds. Of course, if it is in "neutral".

Device

What is the device of the UAZ clutch master cylinder? This element consists of a metal case, a return spring, a piston and a pusher. The latter is connected to the clutch pedal.

Destination

This element serves to transfer forces from the pedal to the working cylinder by converting pressurehydraulic fluid.

If we consider the design in more detail, this element is divided inside into two parts. The top one is used to store and fill the drive with hydraulic fluid. With proper adjustment, its volume should be 75 percent of the total working volume. As for the bottom of the clutch master cylinder, it serves as the working area. When the pedal is not depressed, the piston of the element is pressed against the separating wall by a spring. A gap is formed between the element and the pusher, which, when actuated by the pedal, is filled with hydraulic fluid. At the same time, its supply from the upper part stops. The piston transfers the force from the driver's foot to the working cylinder, and then to the release fork. The pressure level in the system increases significantly.

Thus, the clutch works due to the difference in piston diameters and the increase in its outlets. Unlike mechanical, this type of drive is easier to use, since less effort is needed on the pedal to actuate the fork. When the driver releases the foot, the return spring is activated, which moves the piston of the pusher element to its original position. Fluid circulation between the two chambers resumes again.

Description of faults

The design of such an element as the clutch master cylinder (including UAZ) and its components is very reliable. But it can also be a source of serious problems. One of the most common reasonsmalfunction is a low level of hydraulic fluid in the expansion tank.

It must be checked at every maintenance, otherwise there will be a risk of remaining "clutchless". At a low level, the piston is not able to produce a normal push and actuate the release fork. The car will run in one gear. What can be the reason for the lack of level? This is a depressurization of the system. Check all tubes and hoses that go from the master cylinder to the working one. The latter should also be checked for leaks. It happens that the anther fails. It simply frays from frequent movements of the stem. You can recognize this by dark oily traces. The same traces are found along the way, on the highways themselves (especially if it runs through the wheel arch). If you have non-standard wheels, which is very often true for UAZs, they can wipe the hose when turning. And this applies not only to the clutch, but also to the brake pipes.

In places of bending they are rubber. They must not be allowed to collapse. If there are cracks, it must be replaced immediately.

Inflation

Another reason why the UAZ clutch master cylinder does not work is the presence of air in the system. Even small bubbles can cause clutch failure. This error is closely related to the previous one. Air can be sucked in from damaged tubes and hoses.

Replacing the UAZ clutch master cylinder

If the car does not respond to pressing the pedal, and the fluid level is normal and there is no damage to the tubes, most likely the rod or piston itself is faulty.

As a result, it cannot generate the necessary pressure to operate the system. In order to replace the clutch master cylinder, the UAZ must be placed on a flat surface and pumped out with a syringe. Next, we disconnect the main cylinder from the pedal and seal all the holes from which the liquid flows. This also applies to pipes. Make sure that dirt and moisture do not get inside. This liquid is very hygroscopic. Then we unscrew the nuts securing the cylinder and take it out. After installing a new element, add fluid and bleed the system.

How to upgrade?

To do this, we need a hose and a plastic bottle where the airy liquid will drain. We will pump through the valve on the working cylinder. It is unscrewed with a 10 key. We remove the protective cap from it, put on the hose and call the second assistant. He will press the clutch pedal. At this time, you need to monitor the flowing fluid. It is necessary to press until it becomes homogeneous, that is, without bubbles. After that, check the clutch fluid level in the reservoir again. If it has fallen, top it up to the maximum mark. It is important not to mix fluids from different manufacturers. If you do not know which brand was filled earlier, make a complete replacement. It will be right. Moreover, the service life of the fluid for the clutch and brake system is not more thantwo years. Further, it absorbs moisture and becomes ineffective.

So, we found out what a car's clutch master cylinder is, how it works and how to replace it yourself.