Examination
1. Valve clearances can be checked and adjusted with the cylinder head removed (before putting it on after repair) or during periodic maintenance.
2. Two clearance values are given - for a cold and warm engine (coolant temperature above 35°C). If checking clearances with the engine in the vehicle, warm the engine up to normal operating temperature (it is better to drive 3-4 km), then turn it on and remove the valve cover.
3. With the valve cover removed, rotate the crankshaft (or camshaft if head removed) until the upper convex points of the two cams of the first cylinder are set at the top, and the cylindrical parts of the cams are directed towards the sliding surfaces of the two rocker arms. There is only one such provision, so there is no need to fear for its definition. Minimal shifts to the left or right are not significant. It is important that the cylindrical parts of the two cams of the same cylinder are in contact with the sliding surface of the valve levers.
4. Insert a gap measuring plate of the required thickness between the cam and the lever. If the plate moves freely, without resistance, it is necessary to turn the adjusting ball head bolt until the plate passes with noticeable resistance. How to determine the value of this resistance? Obviously, skill and experience matter here, but a novice mechanic can handle it. Definitely wrong is the setting when the record passes without any resistance. Also incorrect is the installation when the plate does not pass at all. Therefore, we will discuss intermediate settings:
A) when resistance begins to be felt in advance;
b) when the plate, although with great resistance, still managed to advance.
It is this second setting that is more unambiguous. If you have any doubts about the size of the valve clearances, rotate the adjusting bolt so. so that the advance of the plate occurs with obvious resistance, but it is possible. Then we turn the adjusting bolt a little in the other direction, increasing the gap so much that the resistance to advance decreases. The lower limit of adjustment, which is the setting, must not be exceeded (A).
This is all a secret related to valve adjustment. It is known from practice that the size of the gap in the position (b) 0.05 mm less than the gap in the position (A). Moving between (A) And (b), the error that can be made will be equal to 0.03 mm. In comparison with the price, the gap value, for example, 0.35 mm - this error is minimal and you don’t have to worry about the condition of the engine.
Another important piece of information is that a very small clearance can do more for an engine than a very large one. Too little clearance can cause valves to burn out, requiring expensive repairs. A large gap can cause a drop in engine power, louder engine operation, especially audible at slow speeds, and knocking out the valve levers at the points of contact with the valve stem or further increase in clearance. Even if it were necessary to grind the contact surface of the lever, this operation is much simpler. It is necessary to remove the lever as in point 5 when removing the camshaft, and eliminate the dents on the grinding machine, making sure that the grinding surface has the shape of a shaft with a diameter of about 30 mm.
In 1.1 and 1.3 liter engines with an ignition distributor, the valve sequence is as follows, when viewed from the side of the distribution belt - intake-exhaust; inlet-outlet; inlet-outlet: inlet-outlet.
5. Repeat the steps described in subparagraphs 3 and 4 for the valves of the remaining cylinders. If the motor is rotated clockwise (viewed from the timing belt side), it is necessary to adjust the valves in turn, starting with cylinder 3, and then 4 and 2. This is in accordance with the ignition sequence in the engine 1-3-4-2.
6. Put on the valve cover with a new gasket.
7. If the clearances are adjusted after repair for a cold engine or when the valves were adjusted on the removed head, they must be checked again after 1000 km at normal engine operating temperature.
Attention: It is recommended to adjust the valves on a hot engine.
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