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Repair the valve mechanism
| Fig. 2.45. Valve gear: 1 - a bolt 40 Nm + to tighten on 1/4. (90 ?�); 2 - a bolt 50 Nm + to tighten on 1/4. (90 ?�); 3 - phase shifter; 4 - driving the camshaft sprocket; 5 - the valve of 1 system of variable valve timing; 6 - a bolt 10 Nm; 7 - O-ring; 8 - a bolt 10 Nm + to tighten on 1/4. (90 ?�); 9 - housing camshafts; 10 - roller lever; 11 - conical biscuit; 12 - support member; 13 - the valve spring plate; 14 - a spring valve; 15 - the valve stem seal; 16 - repair of the valve guide sleeve; 17 - the directing plug of the valve; 18 - cylinder head; 19 - valve; 20 - EGR valve with potentiometer EGR; 21 - a cover; 22 - the holder; 23 - a cover; 24 - the exhaust camshaft; 25 - the inlet camshaft; 26 - the directing plug
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Details of the valve mechanism shown in Fig. 2.45.
Processing the mounting surface of the cylinder head
| Fig. 2.46. The amount of allowance for processing
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The allowance for processing cylinder head a = not less than 108.25 mm (Fig. 2.46).
NOTE After processing, the landing surface must be correspondingly lower valves (valve seat ring handle), since otherwise the valve piston face. Observe the minimum allowable size. |
Checking the axial displacement of the camshaft
| Fig. 2.47. Checking the axial displacement of the camshaft
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Measure at the removed casing and set the camshaft cover. The maximum tolerance max. 0.40 mm
Valve sizes
NOTE Valves handle prohibited. It allowed only lapping. |
Processing valve seat
NOTE When repairing engines with leaky valve handle or replace the valve seats and valve insufficiency. Particularly in engines with long service life you must check the valve guides for wear. Valve seats should doobrabatyvat just enough to achieve the kind of perfect work surface. Before treatment should calculate the maximum allowance for processing. If you exceed the allowance for processing may be impaired function of the hydraulic control valve clearance (lash), which would entail the replacement of the cylinder head. |
NOTE If the valve is replaced during repair, then the measurements should use a new valve. |
| Fig. 2.49. Measuring the distance between the end of the valve stem and the upper edge of the cylinder head
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Measure the distance between the end of the valve stem and upper edge of the cylinder head (Fig. 2.49). Calculate maximum allowance for processing on the basis of the measured distance and the minimum size. Minimum dimensions The inlet valve - 7.6 mm, Exhaust valve - 7.6 mm Measured distance minus minimum size = maximum allowance for processing. Example Measured distance - 8.0 mm Minimum size - 7.6 mm Max. permissible allowance for processing - 0.4 mm (8.0 mm - 7.6 mm).
NOTE The maximum allowable allowance for processing is shown in Figure processing valve seats as the size of ?�b?�. |
| Fig. 2.50. The processing circuit of the intake valve
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Processing inlet valve seat a = ZH28,7 mm; b = max. permissible allowance for processing; c = 1,5-1,8 mm; Z = lower edge of the cylinder head; a = 45 ?� angle of the valve seat; b = 30 ?� upper correction chamfer; g = 60 ?� the correction lower chamfer.
| Fig. 2.51. The processing circuit of the exhaust valve
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Processing saddle valve a = ZH25,0 mm; b = max. permissible allowance for processing; c = about. 1.8 mm; Z = lower edge of the cylinder head; a = 45 ?� angle of the valve seat; b = 30 ?� upper correction chamfer; g = 60 ?� the correction lower chamfer.
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