They would not need to be adjusted for any reason unless they were disassembled. here are the instruction in that case.
3.8L Engine
- To install:
-
Lubricated all rocker arms with Engine Assembly Lubricant D9AZ-19579-D or equivalent.
Rocker arm seats must be fully seated in the cylinder head, and pushrods must be seated in the rocker arm sockets before final tightening, or engine damage may occur.
-
For each valve, rotate the crankshaft until the valve lifter rests on the heel (base circle) of the camshaft lobe. Position the rocker arm(s) over the push rods, then install the rocker arm seats. Tighten the rocker arm seat retaining bolts to 44 inch lbs. (5 Nm).
-
Final-tighten the rocker arm retaining bolt(s) to 19-25 ft. lbs. (25-35 Nm). For final tightening, the camshaft may be in any position.
-
Clean the rocker arm cover and cylinder head mating surfaces of old gasket material and dirt.
-
Install the rocker arm/valve cover(s). For details, please refer to the procedure located earlier in this section.
-
Connect the negative battery cable.