Insert selection
1. Give the crankshaft to the service station specialists. They will perform the necessary measurements, if necessary, machine the shaft journals and select the liners of the desired diameter.
Shaft installation
Note. New bolts are required to attach the caps or main cap assembly.
2. Make sure the piston cooling oil nozzles (if they are designed) stand in their places in the shaft supports.
3. Wipe the backsides of the liners and the liner bores in the crankcase and in the bearing caps.
4. Insert bushings into main bearing bores and covers. Follow that. so that the protrusions in the liners fit into the cutouts of the bores. Do not touch the working surfaces of the earbuds with your fingers. Keep in mind that the top bearings have one long oil groove along the entire length of the bearing, while the lower bearings have a short groove at each end. Install Thrust Bushing in No. 4 or 5 Support (4 cylinder engine) or on support No. 6 (6 cylinder engine) (pic. 17.4, a, b). If the earbuds are coated with protective grease, wash it off with kerosene. Wipe the earbuds dry with a lint-free cloth. Lubricate the surfaces of all liners with engine oil (fig 17.4, in).
5. Lower a cranked shaft in support so. so that the cranks of cylinders No. 1 and 4 (4 cylinder engine) or #1 and 6 (6 cylinder engine) were at BDC, ready to install the connecting rods. Check the end play of the crankshaft as indicated in 8 paragraph 13.
6. Lubricate the cap bearings with engine oil. Make sure that the tabs on the earbuds fit into the corresponding cutouts on the covers.
7. Replace the covers with liners. deploying them as needed (the protrusions of the liners in the bores of the crankcase and in the covers must be on one side). On the N42 4-cylinder engine, install the cover assembly, making sure that the dowel pins are present. Thoroughly clean the new cover bolts and lubricate their threads with engine oil Screw in and lightly tighten the bolts for the time being. On a 6-cylinder engine, do not forget to fix the oil pick-up pipe bracket with cover bolts No. 5 (Figure 17.7, a, b).
8. Tighten the cover bolts to the required torque (pic. 17.8). On the 4-cylinder N42 engine, first tighten the inner row of cover block bolts, then the outer row.
9. Check that the shaft rotates easily.
M43TU engines and 6-cylinder engines
10. Insert a new oil seal into the crankshaft oil seal rear housing. Install housing with seal and new gasket to engine as directed in chapter 2A or 2B.
11. On a 6-cylinder engine, install the sprocket and oil pump drive chain on the shaft, as indicated in chapter 25.
4-cylinder N42 engine
12. Install the oil pump drive chain and balance shafts, as well as the damper and crankshaft pulley hub, as indicated in chapter 2A.
13. Press in place the front and rear crankshaft seals (see chapter 2A). Install the cuffs so that the grooves on their surfaces coincide with the engine crankcase connector.
14. Obtain a sealant press kit from your BMW dealer. This kit contains Loctite primer. Apply a primer to the mating surfaces of the cylinder block and lower crankcase with a brush.
15. Insert new nozzles for pressing the sealant into the junction of the cylinder block and the lower crankcase. To perform this operation, there is a special tool BMW 119 360, but you can get by with a suitable punch (pic. 17.15).
16. Using the syringe provided in the kit, press the sealant through the nozzle (pic. 17.16), until the sealant appears in the grooves of the front and rear crankshaft seals. Repeat this operation on the other side of the engine.
17. Also lubricate the sealant that has appeared in the grooves of the cuffs with a primer to bind the sealant.
All engines
18. Insert pistons with connecting rods into the engine. as indicated in the next paragraph.
19. On a 4-cylinder engine, install the flywheel (or faceplate), timing chain and its housing, oil damper and sump (see chapter 2A).
20. On a 6-cylinder engine, install the flywheel (or faceplate), primary cam chain and sump (see chapter 2B).