881671 Mercruiser COVER, Cylinder Head

Table 1
Required Tools    
Tool     Part Number     Part Description     Qty    
A     9U-6148     Idler Shaft Puller     1    Start By:
Remove the front housing. Refer to Disassembly and Assembly, "Housing (Front) - Remove and Install".
Remove the valve mechanism cover. Refer to Disassembly and Assembly, "Valve Mechanism Cover - Remove and Install".
Keep all parts clean from contaminants.Contaminants may cause rapid wear and shortened component life.
Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids.Dispose of all fluids according to local regulations and mandates.
Ensure that number one piston is at the top center position on the compression stroke. Refer to Systems Operation, Testing and Adjusting, "Finding Top Center Position for No. 1 Piston".
Illustration 1 g01337345
Alignment of timing marks
Ensure that timing marks (X) on the gears are aligned. Refer to Illustration 1.Alternatively, make temporary timing marks on the gears in order to show alignment.
Loosen the nuts on all rocker arms. Unscrew the adjusters on all rocker arms until all valves are fully closed.Note: Failure to ensure that ALL adjusters are fully unscrewed can result in contact between the valves and pistons.
Illustration 2 g01337783
Typical example
Remove bolt (2), washer (3), and plate (4) .
Remove idler gear (5) from shaft (1) .
Illustration 3 g01337810
Extracting the shaft from the cylinder block
If necessary, follow Steps 6.a and 6.b in order to remove shaft (1) .
Make a temporary mark on the cylinder block in order to show the position of oil hole (Y) .
Use Tooling (A) to extract shaft (1) from the cylinder block.Installation Procedure
Table 2
Required Tools    
Tool     Part Number     Part Description     Qty    
B     9U-7324     Indicator Bracket     1    
7H-1942 Dial Indicator     1    
3S-3268 Indicator Contact Point     1    
7H-1940 Universal Attachment     1    
Keep all parts clean from contaminants.Contaminants may cause rapid wear and shortened component life.
Illustration 4 g01364486
Typical example
If necessary, follow Steps 1.a and 1.b in order to install shaft (1) .
Align oil hole (Y) on shaft (1) with the temporary mark on the cylinder block.
Use a soft faced hammer and a hard wooden drift to install shaft (1) into the cylinder block.Note: Install shaft (1) squarely into the cylinder block. Ensure that oil hole (Y) is aligned with the temporary mark and that the shoulder on the shaft is seated against the face of the cylinder block.
Ensure that plate (4) and idler gear (5) are clean and free from wear or damage. If necessary, replace any components that are worn or damaged.
Ensure that number one piston is at the top center position on the compression stroke. Refer to Systems Operation, Testing and Adjusting, "Finding Top Center Position for No. 1 Piston".
Illustration 5 g01337345
Alignment of timing marks
Lubricate shaft (1) with clean engine oil. Position idler gear (5) onto shaft (1). Ensure that timing marks (X) on the gears are aligned. Refer to Illustration 5.
Lubricate the bearing surface of plate (4) with clean engine oil. Install plate (4), washer (3), and bolt (2) .Note: Ensure that the bearing surface of the plate is toward the idler gear.
Tighten bolt (2) to a torque of 34 N m (25 lb ft).
Use a feeler gauge in order to check the end play of idler gear (2). Refer to Specifications, "Gear Group (Front)" for more informat