2.3.5. Dismantling, check and assembly of a bent shaft

Dismantling
Take off a GRM drive belt, the case of the oil pump, a flywheel, a head of cylinders assembled and the oil pallet. Procedures of removal of details are provided in appropriate sections.
Remove a back plate of the block of cylinders and a back epiploon of a bent shaft.
Uncover rods and inserts of conrod bearings of a bent shaft.
Uncover radical bearings of a bent shaft and remove a bent shaft. Arrange inserts of radical bearings as their compliance to numbers of covers.
Remove a rotor of the sensor of provision of a bent shaft.

Fig. 2.120. Components of a bent shaft



NOTE
For simplification of installation arrange the removed details (covers of rods, inserts of conrod and radical bearings) as their compliance to numbers of cylinders and orientation in an installation site.

Check
Check radical and conrod necks of a bent shaft for absence of damage (teases and holding straps), excessive wear and cracks. Besides, check openings of oil channels for lack of a contamination. Repair or replace a faulty detail.
Check conicity and not roundness of radical and conrod necks of a bent shaft.
Nominal rate:
diameter of a radical neck – 57 mm;
diameter of a conrod neck – 45 mm;
conicity and not roundness of radical and conrod necks – 0,1 mm or are less.

Check of inserts of radical and conrod bearings
Visually check a condition of a surface of each insert (flaking, uneven contact, risks, teases, etc.). Replace defective inserts.

Measurement of a gap in bearings
Measure diameter of radical and conrod necks of a bent shaft.
Measure internal diameters of openings under radical bearings in a bed of a bent shaft (in the block of cylinders and a cover of the bearing) and openings under conrod bearings (in the lower head of a rod and a cover of a rod).
Measure thickness of inserts of conrod and radical bearings.
Calculate a gap in bearings by results of the taken measurements (it is necessary to subtract from value of internal diameter of an opening under the bearing the size of diameter of a neck of a shaft and thickness of an insert of the bearing).
Gap in the conrod bearing: 0,28–0,48 mm.
Gap in the radical bearing (an ustanovlnny limit for new details): 0,024–0,044 mm.

Check of epiploons of a bent shaft
Check forward and back epiploons of a bent shaft for lack of damage or wear of working edges. With defects replace an epiploon.

Check of covers of bearings

Fig. 2.121. Check of an axial gap of a bent shaft


After installation of covers of radical bearings check that the bent shaft rotates smoothly and the axial gap of a bent shaft corresponds to nominal rate. If the axial gap exceeds maximum permissible value, then replace persistent half rings of the bearing and/or inserts of the bearing (fig. 2.121).
Nominal rate: 0,06–0,26 mm.
Maximum permissible value: 0,30 mm.

Check of a rotor of the sensor of provision of a bent shaft
Remove a rotor of the sensor of provision of a bent shaft.
Check a rotor of the sensor of provision of a bent shaft for absence of damage, cracks and wear. If necessary replace a sensor rotor.

Fig. 2.122. Check of a gap between tooth of a rotor of the sensor and a tip of the sensor by means of a depth gage


Check a gap between tooth of a rotor of the sensor and a tip of the sensor by means of a depth gage (fig. 2.122).
Nominal rate of a gap between tooth of a rotor of the sensor and a tip of the sensor: 0,5–1,1 mm.

NOTE
Measure distance from top of tooth of a rotor of the sensor of provision of a bent shaft to an adjusting surface under the sensor on the block of cylinders.
Measure length of a tip of the sensor of provision of a bent shaft as distance between an end face of a tip of the sensor and the landing plane of the sensor.
Calculate a gap as a difference between the specified values.

Assembly
Establish the top inserts of radical bearings in a bed of a bent shaft on the block of cylinders.

NOTE
Be attentive at installation of inserts of the radical bearings removed earlier when dismantling, arrange them according to the adjusting tags put before removal.

Establish a bent shaft. Apply engine oil on radical necks of a bent shaft.
Establish the lower inserts and covers of radical bearings. Tighten bolts of fastening of covers the nominal moment of an inhaling in the following sequence: cover of the central bearing, bearing No. 2 cover, bearing No. 4 cover, cover of the forward bearing and cover of the back bearing.
Tighten bolts gradually in two-three receptions, then tighten the nominal moment of an inhaling.
At installation, covers it is necessary to arrange so that shooters of covers were directed to a pulley of a bent shaft and number of covers corresponded to numbers of cylinders.
Moment of an inhaling of bolts of fastening of covers of radical bearings: 27–33 N · m (60–65 °), bolts of fastening of covers of a rod: 50–53 N · m.
Double-check that the bent shaft rotates smoothly and the axial gap of a bent shaft (a gap between a persistent flange of the central radical bearing and the corresponding cheek of a bent shaft) corresponds to nominal rate.
Nominal rate of an axial gap of a bent shaft – 0,06–0,26 mm.
By means of the special tool (a mandrel for installation of a back epiploon of a bent shaft 09231-2100) install a back epiploon of a bent shaft in the epiploon case, as shown in the drawing. Be attentive, correctly arrange a mandrel not to damage and to deform an epiploon at installation.

Fig. 2.123. Installation of a back epiploon of a bent shaft



Establish a back plate of the block of cylinders and tighten bolts of its fastening.
Establish covers of rods.
Establish a flywheel, the case of the oil pump, the oil pallet and a belt of the GRM drive. Procedures of installation of details are provided in appropriate sections.