Nissan Repair: timing belt, interference engines, timing belt replacement

Question
After replacing the timing belt the aligning marks of camshafts are not matching when crankshaft mark is matching. How can the timing belt be installed correctly? The service manual doesn't recommend rotating camshafts separate from crankshaft.
The car is Nissan Pickup 1989, 6 cylinder, engine VG30i.

Answer
Hi Abraham -

You will need to remove the belt, and readjust the camshaft and crankshafts so they are porperly aligned.

Certain engines, called "interference engines", when both shafts turn independently, the piston(s) may slam into the open valves and cause damage. However at a routine timing belt replacement, it is OK to turn the 2 shafts, as long as it is done by hand, and the travel is minimal.

Hope this helps -
aloha
calvin