891935 Mercruiser O-RING

2. Loosen clamps on hose (2) and push hose from elbow (1). Remove elbow (1) and the water temperature regulator from the cylinder head.3. Remove tube assemblies (5) and (6) from the engine.4. Disconnect temperature sending unit (3) from the cylinder head.5. Remove bolts (4) to disconnect the water pump elbow from the cylinder head. 6. Remove tube assembly from elbow (8). Tube assembly connects to the air fuel ratio control.7. Remove pipe (7) and gasket from cylinder head. 8. Fasten a hoist to the cylinder head. Remove the bolts that hold the cylinder head to the cylinder block. Remove the cylinder head and gasket. The weight of the cylinder head is 150 lb. (68 kg). When the cylinder head is removed, a new spacer plate gasket must be installed. See REMOVE AND INSTALL SPACER PLATE.Install Cylinder Head
When the cylinder head is removed, a new spacer plate gasket must be installed. See REMOVE AND INSTALL SPACER PLATE. 1. Clean the surfaces of the cylinder head and the cylinder block that make contact with each other. Make sure the surfaces are clean and dry. Install a new, dry gasket (1) on the cylinder block.2. Make sure the gasket for elbow (2) is in position.3. Fasten a hoist to the cylinder head and put it in position on the cylinder block.4. Put 5P3931 Anti-Seize Compound on all the head bolts and rocker shaft bolts. Install the head bolts and washers that hold the head in place. Do not tighten bolts at this time. 5. Install the push rods and rocker shaft assembly (3). Install the bolts and washers that hold the rocker shaft assembly in place. 6. Tighten the bolts as follows: a) Tighten bolts 1 through 18 in number sequence to a torque of 115 lb.ft. (155 N m).b) Tighten bolts 1 through 18 again in number sequence to a torque of 185 13 lb.ft. (250 17 N m).c) Tighten bolts 1 through 18 again in number sequence (hand tighten only) to a torque of 185 13 lb.ft. (250 17 N m).d) Tighten bolts A through E in letter sequence to a torque of 32 lb.ft. (43 7 N m).e) Tighten bolts A through E again in letter sequence to a torque of 32 lb.ft. (43 7 N m).7. Make adjustments until the intake valve clearance is .015 in. (0.38 mm) and the exhaust valve clearance is .025 in. (0.64 mm). See ENGINE VALVE LASH as shown in operation LUBRICATION AND MAINTENANCE GUIDE. Tighten the locknuts for the adjustment screws to a torque of 21 5 lb.ft. (29 7 N m).8. Install the water temperature regulator in the cylinder head with the spring toward the inside. See inset of photo B7371.
If the water temperature regulator is installed wrong, it will cause the engine to overheat.
9. Install the gasket and elbow (5) in position. Connect the hose (4) from the radiator tank top to elbow (5) and tighten the hose clamps. 10. Install bolts (6) that fasten elbow (2) to the cylinder head.11. Install tube assemblies (8) and (9) on engine.12. Install the temperature sending unit (7). 13. Install the gasket and pipe (10) on cylinder head.14. Install the tube assembly to elbow (11). Tube assembly connects to the air fuel ratio control.15. Fill the cooling system with coolant to the correct level.end by:a) install air conditioning compressorb) install fan and fan drivec) install exhaust manifoldd) install fuel injection linese) install air cleaner housing