Repair of the cylinder head Tavria Sens Slavuta why the valve is burned out. 

Repair of the cylinder head Tavria Sens Slavuta why the valve is burned out.
Correct welding, welding preparation, welding: • Правильная заварка ГБЦ...
When and why crimping is needed: • Ремонт ГБЦ Зачем нужна...
The cylinder head MeMZ Tavria Sens Slavuta 1,3 has been repaired. The exhaust valve has burned out.
In order to dry the cylinder head, we need to dismantle the axis of the rocker arms with rocker arms. This requires removing the tips of the adjusting screw. They sit between the rocker adjusting screw and the end of the valve stem. We loosen the nut with the head by 12. Unscrew the screws with a screwdriver. With the help of a magnet, we extract the tips. One of them is not removed, because the camshaft cam presses on the rocker arm, and that in turn presses the valve. Press on the valve spring and pull out the tip.
We remove the axis of the rocker arms. The axle fixes the gougeon, and on the other side there is a plug. To dismantle the axle, you need to unscrew the slug and plug. Unscrew the goujon with a screwdriver. Using a square of 8 and a pneumatic gun, unscrew the plug. We take a special bar, and slowly, with small blows, we knock out the axis of the rocker arms. Now you need to remove the rocker arms with springs. Remove the camshaft by turning it around the axis. Let's examine the camshaft journals for scuffs and scuffs, measure their diameters, and pay attention to the cams. Here we are interested in preserving the geometry of the cam itself.
The troubleshooting showed that the camshaft bed and the camshaft itself should not be touched. Now we can start drying the valves. We tap the upper cups with a magnetic desiccant and use a clamp desiccant and a magnet to disassemble the head. Pressing the handle, squeeze the spring, freeing the crackers, and remove them with a magnet. We remove the springs and after that we take out the lower plates with a magnet, which are put under the spring.
Examine the valve seats. As a result, we can say that the seats are in good condition, we just correct the working chamfer, then remove the valve seals and remove the old camshaft oil seal. We check the bushings with an internal gauge. 8.06-8.07. We defect the valves for wear along the stem. Intake 7.92-7.93; release 7.90-7.91. The thermal gap in this head is 0.15 inlet 0.3 mm. We fit into these parameters. We also check the valves for runout, i.e. bent or not. The beat is within normal limits and does not exceed 3 acres.
Recently, many fakes have appeared on the market, so I will check the valve with a magnet. Here the possible cause of the valve burnout was found out. The exhaust valve disc must never be picked up with a magnet. Then the head was checked for leaks. Pressure testing showed that everything is fine here too. As a result, the head is in good condition. Global repairs for replacing bushings, seats, welding windows and other things are not required. And you just need to change the valves, correct the chamfers of the seats, grind the valve-seat interface, and mill the working surface. We restore the chamfers of the valve seats on the machine. The client decided to change the valves and install all new ones. We rub the valves against the seat. We will grind with a suction cup. We apply the lapping paste to the valve disc and with light circular reciprocating movements, for just a few seconds, we rub the valve against the seat.
We mill the surface of the head, after which we must blow through the channels of the cylinder head from the shavings, and wash it in the washing machine, washing out the remaining shavings, and washing off the lapping paste. After washing and drying, we start assembling the head. There is a special mandrel to install the camshaft oil seal. The oil seal is put on this mandrel. Carefully, without much effort, we drive the oil seal into the head to the chamfer in the seat. We put the valve seals using a special mandrel. In this head, the lower plate passes through the oil seal, so first we put the oil seal itself. We place the valves in our lapped places. We put on the lower plates and arrange the springs with the upper plates.
Vkladyvayem v verkhniye tarelki sukhariki. Zasukharim klapany. Stavim raspredval.
Teper' nuzhno vstavit' os' koromysel na mesto. Yesli trebuyetsya, to nuzhno polirnut' poverkhnost' vala i zatochit' kray ot vozmozhnogo naboya, kotoryy mog obrazovat'sya posle yego demontazha. Vstavlyaya os' koromysla, nuzhno obratit' vnimaniye na otverstiye guzhona v valu. Ono dolzhno sovpadat' s rez'boy v golovke. Vybrav nuzhnyy kray nachinayem zavodit' val na svoye mesto. Sobirayem koromysla v obratnom poryadke. Stavim guzhon i probku na svoye mesto.