When installing the cam, the holder has to be evenly and slowly tightened. Make sure the cam goes down evenly. Due to the cam lobe positions, some would be pushing against the valves whilst some would not and the cam would tend to be unbalanced. You have to make sure it goes in balanced.
You must not push the valves as one of the piston would be at TDC and if you push too hard, you would damage the valves. To test if the valves moves, you need to move the piston away from TDC.
The best way to go about is to move the piston away from TDC while you are installing the camshafts and after it is installed and aligned correctly, turn the crankshaft back to its TDC position.
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Wednesday, January 30th, 2013 AT 12:12 PM