The rocker arm assembly uses the principle of leverage to convert the upward thrust of the push rod into pressure on the valve. The rocker arm is divided into an intake valve rocker arm and an exhaust valve rocker arm, which are installed on both sides of the rocker arm seat through the rocker arm shaft on the rocker arm seat. There are bronze (or powder metallurgy) bearing bushings in the center hole of the rocker arm at both ends of the support, which cooperate with the rocker arm shaft and can rotate freely. The rocker arm seat is fixed to the cylinder head with studs. There are adjustment screws and lock nuts in the contact part of the rocker arm and the push rod. The valve clearance can be adjusted by turning the adjustment screws. After the adjustment, it is fixed with the lock nuts to prevent the adjustment screws from loosening during work.
The easy failure of the rocker arm assembly during the long{{0}}term rotation of the diesel engine is the wear of the rocker arm shaft and the rocker arm bushing. When the wear gap between them exceeds 0.25mm, the rocker arm bushing should generally be replaced. Under normal circumstances, their assembly clearance is around 0.06mm.
