810849 Mercruiser CYLINDER HEAD ASSEMBLY (3.0LX)

Do not let the connecting rods hit the bottom end of the cylinder liners or crankshaft when the pistons are removed and installed. Put rubber hose or tape over the threads of the rod bolts to prevent damage to the crankshaft.
3. Remove connecting rod caps (1) from the two connecting rods and push the pistons up until the rings are free of the cylinder liner. 4. Remove pistons (2).5. Do the above steps again for the remainder of the pistons.Install Pistons
1. Turn the crankshaft until the bearing journals for the pistons to be installed are at bottom center.2. Put clean engine oil on the crankshaft journals and on the inside of the cylinder liners. Put clean engine oil on the piston rings and connecting rod bearings.3. Move the piston rings on the piston until the ring openings (gap) are approximately 180° apart.
Never install tool (A) (the ring compressor) without the use of the cylinder liner as a guide. Damage to the piston rings can be the result.
4. Put tool (A) in position on the cylinder liner as shown. Put the connecting rod and piston in position in the same cylinder liner for which it was removed and into the ring compressor. Make sure the "V" mark on the piston is in alignment with the "V" mark on the cylinder block.5. Put the piston into position while the connecting rod is put into position over the crankshaft. 6. Put clean engine oil on bearings, bolt threads and surfaces of the nuts that make contact with the connecting rod caps. Put caps (1) in position on the connecting rods and install the nuts. Tighten the nuts to a torque of 30 3 lb.ft. (40 4 N m). Put a mark on each nut and the end of each bolt. Tighten the nuts 90° more.
When the connecting rod caps are installed, make sure the number on the side of the cap is next to and respective with the number on the side of the connecting rod.
7. Follow Steps 1 through 6 for the installation of the other pistons.end by:a) install cylinder headb) install oil pan platec) install oil pumpDisassemble Pistons
start by: 1. Remove the rings from the pistons with tool (A). 2. Remove retaining ring (3), piston pin (1) and connecting rod (2) from the piston.3. Clean the piston ring grooves on the old piston with an acceptable ring groove tool.4. See USE OF PISTON PIN BEARING REMOVAL AND INSTALLATION TOOLS, SPECIAL INSTRUCTIONS, Form No. SMHS7295 for more information of removal and installation of piston pin bearings. Be sure to remove the bearings from the crankshaft end of connecting rod. 5. Heat the connecting rod in an oven to a temperature of 350°-500°F (176°-260°C). Never use a direct flame to heat a connecting rod.6. Put 6V3029 Spacer (11) in the base plate. Put the connecting rod on the base plate of tooling (B).7. Put the connecting rod piston pin bearing end in the center of the port assembly of tooling (B). Install pin (6) in the center of the bore for the connecting rod bearing.8. Install 6V2049 Adapter (9). Put the hole in the adapter in alignment with the hole in the base plate of tooling (B).9. Install clamp bar (10) and clamp pin (7). The old bearing is pushed out by tooling (B) as the new bearing is installed.10. Put 5P8645 Pusher Adapter (8) in position as shown with the taper side down. The piston pin bearing joint must be in alignment with the hole in adapter (9) and the base plate of tooling (B).11. Put pusher (4) on adapter (8).12. Use tooling (B) to push the new piston pin bearing into the connecting rod until adapter (8) of tooling (B) makes full contact with the connecting rod surface.13. Remove the connecting rod and the old piston pin bearing from tooling (B).14. Check the piston pin bearing bore diameter after the bearing is installed. The correct dimension is 1.7012 .0003 in. (43.210 0.008 mm). The maximum permissible clearance between the bearing and piston pin (worn) must not be more than .003 in. (0.08 mm).Assemble Pistons
1. When old pistons are used, clean the piston grooves with tool (B). 2. Put connecting rod (2) in position in the piston with bearing tab groove (3) and number identification on the same side as the "V" mark on the top of the piston.3. Install piston pin (1) and retaining ring (4).4. For correct piston and ring clearances, see PISTONS AND RINGS in SPECIFICATIONS.5. Install the oil ring spring in the oil ring groove of the piston. The oil ring (7) must be installed on the piston with the ring end gap 180° from the oil ring spring joint. 6. Install oil ring (7) on the piston with tool (A).7. Install intermediate piston ring (6) with the side that has the mark "UP-2" toward the top of the piston with tool (A).8. Install top piston (5) with the side that has the mark "UP-1" toward the top of the piston. Make sure the piston ring end gaps are 90° apart before the pistons are installed.end by:a) install pistons