Tightening Sequence for Main Bearing Cap Bolts on 4-Cylinder Engines
Main Bearing Cap Bolt Tightening Sequence for V6 Engines
1. Position the block so that the bottom is facing up. Unscrew the cap bolts, remove the caps and lay them out in the order they were installed. Remove the old liners from the caps and cylinder block and wipe the caps and beds clean.
2. Clean the outer surface of the new main bearings with oil grooves, and carefully insert them into the cylinder block beds. Insert the corresponding mating bearings into the covers, aligning the projections with the grooves. Do not lubricate the bearings.
3. Install the thrust half rings (in the 3rd support on 4-cylinder engines and in the 2nd on V6).
4. Install the crankshaft and measure the clearances in the main bearings. To do this, place a piece of calibration wire on each main journal of the crankshaft parallel to its axis.
5. Clean the surfaces of the liners in the lids, install the lids (frame of covers on the 3VZ-FE engine) and tighten the bolts in three stages to the specified torque in the specified sequence (see Fig. Tightening Sequence for Main Bearing Cap Bolts on 4-Cylinder Engines or rice. Main Bearing Cap Bolt Tightening Sequence for V6 Engines).
6. On V6 engines, tighten the cover bolts 90° further.
6. Loosen the bolts and carefully lift the covers, compare the thickness of each of the crushed wires with the scale on the package and determine the size of the gap.
7. If the clearance is not within the norm, the reason may be the incorrect selection of the size group of liners. Make sure that there is no dirt or oil between the bearings and the cover surfaces during measurements. If the width of the crushed wire at the ends is very different, then the crankshaft main journal is taper.
8. Remove any remaining wire from the journals and remove the crankshaft.
9. Lubricate the main journals and thrust surfaces of the crankshaft. Lubricate the journals under the oil seal with molybdenum grease and install the crankshaft in the cylinder block. Install the covers in their original places so that the arrows are facing the front of the engine. Install the half rings.
10. Install the upper ring by rotating it along the crankshaft journal. The grooves in the ring should be facing outward.
(The publication is taken from the website: ToyotaMan.ru)
11. The lower rings are inserted into the groove on the cover.
12. Tighten the bolts in three stages to the specified torque in the sequence shown (see Fig. 4-Cylinder Engine Main Bearing Cap Bolt Tightening Sequence or Fig. V6 Engine Main Bearing Cap Bolt Tightening Sequence).
13. Check the freedom of rotation of the crankshaft.
14. Check the crankshaft axial clearance (see subsection 3.3.9.1).
15. Install the rear oil seal (see subsection 3.1.14 or subsection 3.2.15).