Baotou North Benz parts, cam and tappet back of the impact of abnormal sound, sometimes loud, will be in a short period of time to wear a bad cam, so that it completely scrapped, causing the failure of the reasons may have the following points:
(1) the cam line is wrong. Due to wear or overhaul grind with the wrong cam cam profile, which deviates from the normal linear design (mainly ascent).
(2) tappet hole deviation. Mainly caused by machining errors and excessive partial wear.
(3) the tappet does not rotate. Most are caused by abnormal wear or displacement in service.
(4) lack of lubrication. Accidental factors cause oil blockage or splash and lack of oil mist.
(5) surface abrasion. If the rocker arm or valve guide is blocked, the contact pressure on the cam surface will be too large.
Baotou North Benz parts cam and tappet impact abnormal sound is heard most clearly at the tappet chamber cover panel. When the sound is small, it can be extended to each tappet hole by means of a push rod from the opening of the tappet chamber cover plate. Distinguish which tappet is impacting the cam. Remove the abnormal sound of the tappet, observation and cam contact and the bottom surface of the catheter body with the cylinder, for picking and scratches. If the friction marks on the underside are striped, the tappet does not rotate. Showing crossed bars indicating that the tappet rotation is blocked. As long as the cam and tappet surfaces have not been grazed, try again. Until all the lifters are able to rotate without noise. If one of the cam or tappet has been grazed, it should be checked whether the other one is worn with it or not. The scraped parts can not be used continuously.
In general, the fault is always the first abnormal sound, after contact traces, finally will cause damage to the components, so when found abnormal sound, if not to check the friction and seizure marks, the fault is still in the early stage. Sometimes, in order to find fault, it needs to operate at the most exciting speed at the abnormal sound for a period of time and then check it so that it can see the mark and find the fault.
If you hear the noise, there is no trace in the Baotou North Benz accessories tappet and the bottom surface of the cylinder, and the cam rise sections connected with the base circle where there is a line that is usually a sign of imprinting, tappet card. The deflection of tappet hole deviation and excessive wear should be checked. If a grainy or watermark bar appears on the surface of the cam, this is a sign of excessive contact pressure on the cam surface. Should check the rocker arm and valve guide, hysteresis, spring pressure is too large and so on. If the surface of the cam is yellow, the problem of insufficient lubrication shall also be checked, in addition to the inspection of the preceding paragraph. If the knocking of the cam is clear and rhythmic, the speed increases as the speed rises, and at the same time, there are two upward stop prints on the outer cylindrical surface of the tappet, which is caused by the obstruction of the upper and lower movements of the tappet. If the knocking sound obvious, but do not see any scratches and imprinting, doubt the cam profile (mainly ascent) is not correct.