How to align the timing marks on the zd25 camshaft?

[DiDiana]

For the zd25tcr engine, the timing marks on the camshaft need to be aligned with the marks on the high-pressure pump. The '0' mark on the front face of the camshaft pulley should align with the central vertical line on the rear timing case. Below is additional information about the camshaft: Camshaft working principle: The camshaft is positioned within the cylinder head, above the combustion chamber, directly driving the rocker arms and valves without the need for long pushrods. Compared to pushrod engines with the same number of valves (i.e., overhead valve configurations), overhead camshaft designs require fewer reciprocating components. This significantly simplifies the valve train structure, markedly reduces engine weight, and simultaneously improves transmission efficiency while lowering operational noise. Camshaft usage considerations: The camshaft is one of the critical components of an engine. The hardness of the cam lobe and the depth of the chilled layer are key technical indicators that determine the camshaft's service life and engine efficiency. While ensuring the cam has sufficiently high hardness and an adequate chilled layer depth, attention must also be paid to preventing excessive carbides in the journal areas to maintain good machinability.