How to Distinguish Between Top Dead Center of Cylinder 1 and Cylinder 4?

1 Answers
ReedRose
07/28/25 2:42pm
When installing the timing belt, rotate the engine to the top dead center position of cylinder 1, and check the position of the camshaft lobes to determine the orientation of the intake and exhaust cam lobes of cylinder 1. When the exhaust valve of cylinder 4 just closes, the intake cam lobe is in the compression state, indicating the top dead center of cylinder 1. Conversely, it indicates the top dead center of cylinder 4.
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