42724A 4 Mercruiser COVER ASSEMBLY

2. Remove main bearing caps (1).3. Remove the crankshaft from the cylinder block. Weight of the crankshaft is approximately 145 lb. (65 kg). 4. Remove main bearings (2) from the block and from the caps. Remove the thrust bearings.
Typical Example5. Use tooling (A) to remove gear (3) from the crankshaft.Install Crankshaft And Gear
Typical Example1. Heat the crankshaft gear to a maximum temperature of 600 °F (315°C). Install the gear on the crankshaft with the "C" mark on the gear toward the pulley end of the crankshaft.2. Clean the surfaces on the cylinder block for the main bearings. Install the upper halves of the main bearings in the block. Put clean engine oil on the bearings.3. Turn the camshaft so the "C" mark on the camshaft gear will be toward the "C" mark on the crankshaft gear when the crankshaft is installed. Put the crankshaft in position in the cylinder block with a hoist. Make sure the timing marks on the camshaft gear and crankshaft gear are in alignment as shown.4. Clean the Nos. 1 and 5 main bearing caps. Install new bearings in the caps. Put clean engine oil on the bearings. Temporarily install the caps to hold the crankshaft in place.
Make sure part number on cap is toward front of engine, and number on bottom of cap is the same as number on block when caps are installed.
5. Clean the Nos. 2,3 and 4 main bearing caps. Install new bearings in the caps. Put clean engine oil on the bearings, bolts, threads and surfaces of the washers for the caps. 6. Check the bearing clearance with Plastigage (A). Install the caps and tighten the bolts to a torque of 30 3 lb.ft. (40 4 N m). Put a mark on each bolt head and the bearing caps. Tighten the bolts 90° more. Remove the bearing caps and measure the width of the Plastigage. The main bearing clearance (Plastigage width) with new bearings must be .0030 to .0065 in. (0.076 to 0.165 mm). The maximum permissible clearance with used bearings is .010 in. (0.25 mm).7. Put the caps in position on the engine and install the washers and bolts. Tighten the bolts to a torque of 30 3 lb.ft. (40 4 N m). Put a mark on each bolt head and the bearing caps. Tighten the bolts 90° more. Do not use an impact wrench.8. Remove the Nos. 1 and 5 main bearing caps. Follow the procedure in Steps 5 and 6 and check the main bearing clearance for the Nos. 1 and 5 main bearings.9. Follow the procedure in Step 7 and install the No. 1 main bearing cap. 10. Put clean engine oil on thrust bearings (1). Install the bearings with the steel back against the cylinder block. Install the No. 5 main bearing cap. Tighten the bolts for the cap with the procedure in Step 7. 11. Check the crankshaft end play with tool group (B). The end play is controlled by the thrust bearings on the No. 5 main. The end play with new bearings must be .0025 to .0145 in. (0.064 to 0.368 mm). The maximum permissible end play with used bearings is .025 in. (0.64 mm). If a replacement has been made for any of the timing gears, it will be necessary to check the engine timing to make sure it is correct. See INSTALL FUEL INJECTION PUMP HOUSING AND GOVERNOR.END BY:a) install pistonsb) install timing gear cover