What are the symptoms of camshaft wear?

[ONevaeh]

The symptoms of camshaft wear include increased engine noise, disruption of the valve opening pattern, reduced valve lift, and shortened valve opening and closing overlap time. This affects the accuracy of the valve timing, leading to insufficient air intake and incomplete exhaust emission. It also makes it difficult to adjust the clearance between the valve stem end and the tappet, resulting in reduced vehicle power. The camshaft is the main driving component in the valve train, used to control the timing of the exhaust valve's opening and closing and to drive other accessories such as the fuel pump, oil pump, and distributor. The camshaft can be positioned in three ways: lower-mounted, mid-mounted, and upper-mounted. In a lower-mounted valve train, the camshaft is located in the crankcase; in a mid-mounted valve train, it is located in the upper part of the engine block; and in an upper-mounted valve train, it is located on the cylinder head.