Replacing the valve guides is necessaryto carry out at repair of a head of the block of cylinders, and also at excessive wear of elements. Domestic cars have a significant advantage - they can be repaired on their own, with a minimum number of tools and accessories on hand.
Also in stores there is a large selection of spareparts from different manufacturers, so there’s never a problem with them. However, when adjusting the valves on front-wheel drive cars, washers are required, they are not always commercially available. But the guide bushings are relatively simple to change. This procedure will ensure the normal functioning of the engine.
Why do I need a sleeve
In order to ensure stable and uninterrupted operation of the internal combustion engine, the head of the construction block is used. It contains the following elements:
- Valve guides.
- Valves.
- Plates and valve springs.
- Crackers for fixing items.
- Epiploons for prevention of hit of oil in combustion chambers.
When replacing the valve guides VAZ-2109need to ensure maximum cleanliness. All work should be carried out only on the workbench, before installation it is necessary to clean all elements from contamination. Otherwise, the dust particles will get inside the combustion chamber and damage the surface of the sleeves.
The valves are installed in the holes throughwhich passes the fuel mixture and exhaust gases. The more precisely the valve system will work, the higher the engine power and its torque. If the guide turns out to be slightly deformed, this will result in the fact that the piston foot cannot move normally - the friction force will interfere with it. Because of this, the efficiency of the entire mechanism is reduced several times. The likelihood of a broken timing belt increases.
Valve system design
Each valve has plates - working partsdisc shape. They are as close as possible to the nest. To ensure the most dense connection, it will be necessary to do grinding during repair. For this special abrasive paste is used. The second part of the valve is a rod with slots at the end. With its help the forward and return movement to the plate is transmitted. Due to this, the hole in the head of the block opens and closes in time.
To ensure the valve moves strictly along the axisused bushings. Their design is such that the valve stem cannot move to the sides - only up or down. There are no gaps between the inside of the sleeve and the stem, so it will not be able to pass engine oil into the combustion chamber through it. Although seals are installed for this purpose. But over time, it is necessary to replace the valve guides, as they are still destroyed by the action of friction.
When to change bushings
It is imperative to make sure that the bushings are faulty. Similar signs may occur when the packing fails. When do I need to change the guides on the valves?
- In the presence of engine oil in the combustion chambers. At the same time from the exhaust pipe is blue smoke, increases oil consumption.
- If there are knocks and other extraneous sounds coming from the side of the cylinder head.
- If the head of the block is being repaired, be sure to install new guides.
- When replacing all valves in the cylinder head after damage (in the event of an open timing belt).
- During the overhaul of the head unit.
Preparation for repair
The most thorough need to repairheads and timing mechanisms. It is necessary to have several special tools, the set of keys will obviously not be enough. Replacing the valve guides of the VAZ-2106 is performed in the same way as on any other model. The design is different, but only slightly. The wizard will need this tool:
- Mandrel for a vypressovka of guides fromseats It can be made on a lathe or purchased at the store. Factory products have a handle and a working part, which is a metal rod with a diameter slightly smaller than that of the sleeve. At the end of the part is thinner - it freely penetrates into the inner hole of the valve sleeve.
- Special reamers with dimensions of 8.022 ..8.040 (for intake valves) and 8.029..8.047 (for exhaust valves). With the help of these devices, which are elongated drills, it is possible to increase the diameter of the holes in the head of the block for fitting the guides to the desired size.
All work is desirable to carry out with the head removed. Be sure to remove the valves, seals, camshaft and other elements.
Sequencing
Clean up all the elements of the head of the block in advance. Put new guides in the freezer a couple of days before the repair. The algorithm for doing this is:
- Insert the mandrel from the inside, strike with a hammer to knock out the old bushings. Do this as carefully as possible, so as not to damage the cylinder head elements. Remove all guides.
- Clean the place for the installation of new bushings. Use a thinner and a brush for this. Afterwards, be sure to blow with compressed air.
- Warm up the head of the unit on the electric stove to 100 degrees. During this process, the bore holes will widen, it will be easier to install the bushes.
- Install retaining rings on bushings.
- Insert the guides into the mounting holes, drive them with the mandrel up to the stop.
Completion of work
Прежде чем устанавливать клапаны, доработайте internal holes in the sleeves. To do this, allow the head of the unit to cool completely. Try installing valves - if they are not included, then use the reamer to enlarge the hole. First use the smallest size. Be sure to try on the valve after each pass.
You need to achieve maximum planting densityvalve in the sleeve. When replacing the valve guides of the VAZ-2112, be sure to mark the position of the intake and exhaust ports. The inlet sleeves are shorter than the exhaust, so when installing them can not be confused.
