See also:

Ford Sierra Service Manual
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Diagram 2a: 1986-on Lighting all models
Diagram 2a: 1986-on Lighting all models ...

Camshafts and cam followers - removal, inspection and refitting
Note: Once the timing chain has been removed from the camshaft sprockets, do not turn the crankshaft until the timing chain has been correctly refitted - this is to prevent contact between the val ...