 | 1. Check the bearing surface for the installation of camshafts in the presence of cavities, scratches, burrs or other signs of excessive wear. In the case of defects should be replaced by a head. |
2. Measure the outer diameter of each of the shaft bearing journals. Record measurements and compare them with those given in the Specifications nominal values. Measure the internal diameter of the bearing in the cylinder heads and subtract from the results of the last measurement results corresponding to the first. The resulting difference will be the amount of clearance in the shaft bearings. Compare the data to requirements of Specifications. If necessary, replace the rolls and / or the heads. 3. Evaluate the radial runout shafts arranging them in the V-shaped blocks and using a dial gauge type plunger. Rotate the shaft slowly in blocks, write statements and compare their nominal values (see. Specifications). If necessary, replace the appropriate shaft.  | 4. Use a micrometer to measure the height of the cam shaft. Compare results of measurements to requirements of Specifications, then subtract them from the past in order to determine the degree of wear of the cams. If the wear exceeds the maximum permissible value (see. Specifications), replace the appropriate shaft. |
5. Evaluate the condition of working surfaces of the valve lifters.  | If the contact surface of the push rod is worn, it makes sense also to evaluate the state of the corresponding cam lobes of a camshaft / shim on engines DOHC.
On SOHC engine tappets must be kept upright to avoid the ingress of air (see. Part Engines SOHC of this chapter). |
 | 6. Use a micrometer to measure the outer diameter of each pusher. Compare results of measurements to requirements of Specifications. Worn over the allowable limit, replace pushers. |
 | 7. Measure the diameter of each pusher, compare the results of measurements to requirements of Specifications. If necessary, replace the assembly guide (engines SOHC), a cylinder head (engines DOHC). |
8. Subtract the value of the outer diameter of a pusher of the inner diameter of the corresponding slots in the guide / head to determine the backlash of landing of pushers in nests - when installing new components (tappets, rail / head) there is a possibility of the output parameter of range.
9. On engines SOHC vote wear rockers and their axes (see. Part Engines SOHC of this chapter). Excessive wear on the rocker arm must be replaced - in any case, do not attempt to conduct their recoverable depreciation.
10. Remember that the status of all components - new or fit for further use of old before installation should be compulsorily tested. |
