Removing the camshaft was discussed in the article - "Removing the cylinder head of the VAZ-2123 engine".
With increased wear of the camshaft in the engine, the oil pressure may drop and the knock of valves may appear, even with serviceable hydraulic lifters.
1. We disassemble the camshaft bearing housing, for which we unscrew the two bolts securing the camshaft thrust flange with a 10 key
2. Remove the thrust flange from the groove in the front bearing journal of the shaft.
3. Remove the camshaft from the bearing housing by sliding it forward.
When removing the camshaft from the bearing housing, be careful not to damage the surfaces of the camshaft journals with the sharp edges of the cams.
4. Inspect the camshaft.
Seizures, nicks, scratches, enveloping of aluminum from the bearing housing are not allowed on the working surfaces of the journals.
5. On the working surfaces of the cams, wear over 0.5 mm is not allowed, as well as scuffing and wear of the cams in the form of a cut.
Replace the defective shaft.
6. We measure the diameters of the bearing journals of the shaft. They should be (counting from the front):
1 - 45.915-45.931 mm;
2 - 45.615-45.631 mm;
3 - 45.315–45.331 mm;
4 - 45.015-45.031 mm;
5 - 43.415-43.431 mm.
7. Inspect the camshaft bearing housing.
Cracks on the body are not allowed.
Risks, scratches, scuffs, excessive wear are not allowed on the working surfaces of the neck supports.
8. Measure the inner diameters of the camshaft housing supports.
They should be (counting from the front):
1 – 46,000–46,025 мм;
2 – 45,700–45,725 мм;
3 – 45,400–45,425 мм;
4 – 45,100–45,125 мм;
5 – 43,500–43,525 мм.
If the clearances between the shaft journals and the bearings exceed 0.2 mm (wear limit), replace the housing and, if necessary, the camshaft.
Install a new camshaft and bearing housing, as well as all removed assemblies and parts in the reverse order of removal.
Before installing the camshaft in the bearing housing, lubricate the working surfaces of the camshaft journals and cams with engine oil.
Tighten the bearing housing retaining nuts in the order shown in the figure. The tightening torque of the nuts is 18.33-22.6 Nm (1.87-2.3 kgf.m).