How do you remove, inspect, and install rocker arms and pushrods, and adjust valve clearance on Mercury Grand Marquis?

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Remove the valve cover(s) from the cylinder head(s). Beginning at the front of one cylinder head, remove the rocker arm fulcrum bolts and store them separately in marked containers to ensure they will be reinstalled in their original locations. If the pushrods are the only items being removed, loosen each bolt just enough to allow the rocker arms to be rotated to the side for pushrod removal. Lift off the rocker arms, fulcrums, and fulcrum guides if used, and store them in marked containers with the bolts. Remove the pushrods and store them separately to avoid mixing during installation; a perforated cardboard box is ideal for pushrod storage. Check each rocker arm for wear, cracks, and damage, especially where the pushrods and valve stems contact the rocker arm faces, ensuring the hole at the pushrod end of each rocker arm is open. Inspect the pivot area and fulcrum for wear, cracks, and galling, replacing worn or damaged rocker arms and fulcrums as necessary. Inspect the pushrods for cracks and excessive wear at the ends, rolling each across a piece of plate glass to check for bending. Before tightening the rocker arm bolts, ensure both lifters for each cylinder are on the base circle of the cam lobe with both valves closed. Lubricate the lower end of each pushrod with clean engine oil or moly-base grease and install them in their original locations, ensuring each pushrod seats completely in the lifter. Apply moly-base grease to the ends of the valve stems and the upper ends of the pushrods before positioning the rocker arms, fulcrums, and guides, and also to the fulcrums to prevent damage to mating surfaces before engine oil pressure builds up. Set the rocker arms and guides in place, then install the fulcrums and bolts. Adjustment is typically needed after replacing valve train components or significant grinding of the valves or seats. Using a lifter bleed-down tool, press on the rocker arm until the lifter leaks down, then check the clearance between the valve stem and rocker arm with a feeler gauge, comparing the results to the specifications and recording them for future reference. Repeat the procedure for each valve in the specified order, checking the intake and exhaust valves with the crankshaft in position 1, then rotating the crankshaft one complete revolution to position 2 and checking the specified valves, followed by a 1/4-turn to position 3 for the remaining valves. Clearance can be adjusted using different length pushrods available from the dealer; use a shorter pushrod for insufficient clearance and a longer one for excessive clearance.

Genuine Mercury Grand Marquis Rocker Arm

8 Rocker Arms found

Mercury Grand Marquis Arm Assembly - Valve Rocker

Mercury Grand Marquis Arm Assembly - Valve Rocker

Mercury Grand Marquis Arm Assembly - Valve Rocker

Mercury Grand Marquis Arm Assembly - Valve Rocker

Mercury Grand Marquis Arm Assembly - Valve Rocker

Mercury Grand Marquis Arm Assembly - Valve Rocker

Mercury Grand Marquis Arm Assembly - Valve Rocker

Mercury Grand Marquis Arm Assembly - Valve Rocker

Mercury Grand Marquis Rocker Arm

Mercury Grand Marquis Rocker Arm Parts Questions & Experts Answers

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