Checking the lubrication clearance of the main bearings
1. Install new main bearing shells.
2. To measure the lubrication gap, you can use an internal micrometer or other special device, but the most accurate and easiest method is to use a special plastic gauge.
3. Clean the crankshaft, bearings and oil holes, then carefully install the crankshaft onto the bearings.
4. Place a piece of plastic on each of the main bearings along the shaft axis.
5. Install the main bearing caps, being careful not to displace the plastic. Tighten the cover mounting bolts to the specified torque in the sequence shown. Do not turn the crankshaft.
6. Unscrew the bolts and carefully remove the covers.
7. Compare the width of the crushed film with a special scale to determine the size of the lubrication gap.
8. If the gap size does not meet technical requirements, install liners of a different size. If necessary, bearings can be turned.
9. Carefully remove any traces of film from the shaft and bearings.
Final installation of the crankshaft
1. Carefully remove the crankshaft.
2. Install the central main bearing half rings.
3. Clean the surface of the bearings and lubricate them with grease or motor oil.
4. Check that the crankshaft bearings are clean and install the crankshaft in place.
5. Lubricate and install the lower bearings. Install the main bearing caps and insert the mounting bolts.
6. Lubricate and install the lower bearings. Install the main bearing caps and insert the mounting bolts.
7. Tighten all main bearing cap bolts to the specified torque in the sequence shown.
8. Turn the crankshaft by hand several times and check for ease of movement.
9. Check the crankshaft axial play and install the rear oil seal.