896895 Mercruiser NUT, (M12)

Start By: a. remove valve covers
Do not let the tops of the fuel injection nozzles turn when the fuel lines are loosened. The nozzles will be damaged if the top of the nozzles turn in the body.
1. Use tooling (A) to loosen the nuts on the fuel injection line.2. Remove fuel injection lines (1).3. Disconnect fuel injection line nut (2) from head adapter nut (3).4. Remove adapter nut (3) and the O-ring seal. 5. Remove four bolts (4) that hold rocker arm assembly (5), and remove rocker arm assembly (5).Install Rocker Shaft Assemblies
1. Check the adjustment of the valve bridges. See Install Push Rods, Valve Lifters And Valve Bridges. 2. Loosen all the rocker arm adjusting screws on rocker shaft assembly (5).3. Install rocker shaft assembly (5).4. Clean the bolts that hold the rocker shaft assembly. Put 2P2506 Thread Lubricant on the bolt threads, and install them.5. Be sure the rocker arms and push rods are in alignment before the rocker shaft assembly bolts are tightened.6. Tighten the rocker shaft bolts in the following sequence.a. Tighten bolts (1) through (4) in numerical sequence to a torque of 280 27 N m (210 20 lb.ft.).b. Tighten bolts (1) through (4) in numerical sequence to a torque of 440 20 N m (320 15 lb.ft.).c. Tighten bolts (1) through (4) in numerical sequence again to a final torque of 440 20 N m (320 15 lb.ft.). 7. Install a new O-ring seal on head adapter (7), and put clean engine oil on it.8. Put fuel injection line (8) in position, but do not tighten the nuts.9. Install adapters (7), and connect fuel injection lines (8).10. Connect fuel injection lines (6) to adapters (7).
Do not let the tops of the fuel injection nozzles turn when the fuel lines are tightened. The nozzles will be damaged if the top of the nozzles turn in the body.
11. Use tooling (A) to tighten the fuel injection line nuts to a torque of 41 7 N m (30 5 lb.ft.).12. Adjust the valve clearance settings. The clearance for the intake valve is 0.38 mm (.015 in.). The clearance for the exhaust valves is 0.76 mm (.030 in.). See Valve Clearance Setting in Testing And Adjusting.End By:a. install valve coversDisassemble Rocker Shaft Assemblies
Start By: a. remove rocker shaft assemblies 1. Remove retainer (1) from the end of the shaft.2. Remove the washers and rocker arm (2). 3. Use tool (A) to remove the pin that holds bracket (3) to the rocker arm shaft.4. Remove bracket (3), rocker arm (4) and the spring.5. Remove the remainder of the rocker arms. The center brackets do not have pins.Assemble Rocker Shaft Assemblies
Make sure all parts of the rocker shaft assembly are clean before assembly. 1. Put clean engine oil on shaft (3).2. Install the center springs, rocker arms and bracket.3. Install spring (1), rocker arm (4) and bracket (2).4. Put tape around the shaft on each side of bracket (2) as shown. Put the hole in bracket (2) in alignment with the hole in shaft (3). Put a mark on each piece of tape in alignment with the hole in bracket (2).5. Install pin (5) until it is extended 12.7 1.0 mm (.50 .04 in.) above the surface of bracket (2). Make sure pin (5) is in alignment with the marks on the tape before the pin is installed. Remove the tape.6. Install rocker arm (6), washers (7) and retainer (8). Install enough washers until the end play on each end of the shaft is 0.30 to 1.40 mm (.012 to .055 in.).End By: a. install rocker shaft assemblies