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Checking the hydraulic valve lifters
Proper installation of the valve clearances largely determines the engine. If the valve clearances are too large, noise increases and decreases engine efficiency because the valves are opened too late and closing early. If the valve clearance is too small, the valves can not be closed completely on the hot engine, which can cause serious damage. On engines mounted hydraulic tappets, which automatically under pressure in the lubrication system compensate for the gap between the cam of the camshaft and the corresponding valve stem. Therefore, the operation does not require regular inspection and adjustment of valve clearance. However, the need to use engine oil of good quality and recommended viscosity and replace it with the desired frequency. When starting a cold engine there is a slight delay in equalizing the engine oil pressure in all parts of the engine, especially in a hydraulic pusher. Valves can knock about 10 seconds, and then begin to work silently. If the engine does not start a few days, the valves can knock over a long time, since almost all of the oil flows from the top of the engine and the working surfaces of bearings. At this time, care must be taken not to damage the motor: Avoid sudden changes in engine operation, until all jacks are filled with engine oil. When engine warming rate of rotation for 2 minutes should not exceed the speed of "fast" idling (from 2000 to 2500 min-1), or until no knock valves. If the noise does not stop pushers, stop the engine and perform the following steps. Make sure that the engine temperature is at least 80 ?� C - the engine should be heated. Remove the cylinder head cover. While cranking the engine, set the cam located on verifiable pusher, straight up, so it is not working on a pusher.
| Fig. 1.3.72. Check of a free wheeling of a pusher
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Press pusher a wooden or plastic wedge (Fig. 1.3.72). If the free wheeling of a pusher greater than 0.2 mm, the plunger must be replaced. Install the cylinder head cover. Wait 30 Mindo starting the engine for the hydraulic tappets to come back to normal, because otherwise the pistons may hit the valves.
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