0435223 JOHNSON CARBURETOR ASSY.

Make sure the upper and lower halves of the main bearings are installed so the bearing tabs fit into the notch in the cylinder block and main bearing caps.
1. Clean the bearing surfaces in the cylinder block. Install the upper halves of the main bearings in the block.2. Heat the crankshaft gear to a maximum temperature of 315° C (600° F). Install the gear on the crankshaft. Fasten a hoist to the crankshaft and put the crankshaft in position in the cylinder block with all timing marks in alignment.3. Clean the bearing surfaces of the main bearing caps. Install the lower halves of the main bearings in the caps. When the bearing clearance is checked and the engine is in a vertical position, such as in the vehicle, the crankshaft will have to be lifted up and held against the upper halves of the main bearings to get a correct measurement with the Plastigage. The Plastigage will not hold the weight of the crankshaft and give a correct indication. If the engine is in a horizontal position, it is not necessary to hold the crankshaft up. Do no turn the crankshaft when the Plastigage is in position to check clearances. 4. Check the main bearing clearances with Plastigage (B) as follows:a. Put a piece of Plastigage (B) in position as shown.
Make sure the part number on the main bearing cap is toward the front of the engine and the number on the main bearing cap is the same as the number on the cylinder block on the left side of each main bearing cap.
Do not turn the crankshaft when Plastigage (B) is in position.b. Install the main bearing caps. Put 2P2506 Thread Lubricant on the bolt threads and the face of the washers and install the bolts. Tighten the bolts to a torque of 40 4 N m (30 3 lb.ft.).
Do not use an impact wrench to tighten the bolts the additional 90°.
c. Put a mark on each bolt and main bearing cap, then tighten the bolts 90° more.d. Remove the main bearing caps. Remove Plastigage (B) and measure the width of the Plastigage. The main bearing clearance must be 0.076 to 0.165 mm (.0030 to .0065 in.). The maximum permissible clearance with used bearings is 0.25 mm (.010 in.). 5. Put clean oil on thrust bearing (3) for the No. 7 main bearing. Install the thrust bearing with the identification "BLOCK SIDE" toward the cylinder block. Engines that have a spacer plate have a thrust bearing that has a tab on it and must be installed with the tabs of the thrust bearings in the machined area in the cylinder block. The tabs will not let the thrust bearings be installed backward.6. Install the main bearing caps and tighten the bolts as in Steps 4b and 4c. 7. Check the crankshaft end play with tooling (C). The end play is controlled by the thrust bearings on the No. 7 main bearing. End play with new bearings is 0.064 to 0.368 mm (.0025 to .0145 in.). The maximum permissible end play with used bearings is 0.65 mm (.025 in.).End By:a. install pistonsb. install timing gear coverc. install rear mounting plated. install engine