4.1.12. Removal, check of a state and installation of the camshaft

Check of an axial side play and side beating

 PERFORMANCE ORDER

1. Check of an axial side play is made as follows:
   a) Install the camshaft in the engine and fix it by covers of bearings;

   b) Fix the dial measuring instrument on a head of cylinders, having rested it a plunger against a shaft end face (see an accompanying illustration);

   c) Having used the big screw-driver as the lever, take away a shaft against the stop back and nullify the measuring instrument, then push a shaft forward and consider instrument reading;
   d) Compare result of measurement to requirements of Specifications;
   e) The excessive size of an axial side play speaks about wear of the camshaft, or a head.
2. For check of a side beating:
   a) Lay the camshaft removed from the engine in two V-shaped prisms, then press a plunger of the dial measuring instrument to a neck of the central bearing and measure beating size at rotation of a shaft;
   b) Compare results of measurement to requirements of Specifications;
   c) At excessive fight the camshaft is subject to replacement.

Removal

 PERFORMANCE ORDER

1. Uncover a head of cylinders (see Removal and installation of a cover of a head of cylinders).
2. Bring the piston of the first cylinder into the provision of VMT (see Reduction of the piston of the first cylinder in the provision of the top dead point (TDP)).
3. Remove the ignition distributor (see the Head Elektrooborudovaniye of the engine).
4. In case of need turn out a bolt of fastening of a cogwheel of the camshaft for the purpose of removal it from a pin.

For the purpose of blocking of a shaft from a provorachivaniye pass the screw-driver through one of openings in a cogwheel.


5. Remove assembly of yokes (see Removal, check of a state and installation of assembly of yokes). If covers of bearings of the camshaft are subject to removal from assembly, they need to be marked as installation (put down tags asymmetrically for a guarantee of the correct orientation of covers).

6. Take a bent shaft (see an accompanying illustration).

Check

 PERFORMANCE ORDER

1. Check bearing gangs of a shaft and internal surfaces of covers of bearings for existence of scratches and zadir. In case of detection of serious defects the head of cylinders is subject to replacement on new or restored. By means of the calibrated plastic wire (Plastigauge set) measure the size of working gaps in bearings. Compare results of measurements to requirements of Specifications.

Instructions for use of the Plastigauge set are provided in Installation of a bent shaft and check of working gaps of radical bearings and Installation of conrod and piston assemblies and check of size of working gaps in conrod bearings of a bent shaft of the Part the General and capital repairs of the engine of the present Chapter. If the gap of any of bearings exceeds the limit of admissible range, replace the camshaft.


2. Estimate degree of wear of cams of the camshaft:
   a) Attentively examine the forming surfaces of working ledges of all cams, checking them for existence of scratches, zadir and signs of uneven wear;
   b) In case of detection of defect of at least one of cams replace the camshaft. Do not forget about need of identification of causes of wear – check motive oil for presence of abrasive particles at it. Check passability of the oil pump and all maslotok (wear of raising of cams is most often connected with pollution of oil or violation of its giving);

   c) By means of a micrometer measure height of cams (see an accompanying illustration). Compare results of measurements, in case of need replace the camshaft.

3. Check working surfaces of yokes of the drive of valves for existence of signs of wear, attritions, cavities and other defects.
4. In case of identification of any of the listed above defects it is necessary to check a condition of motive oil and serviceability of its giving in a head of cylinders. Only having established and having removed a cause of infringement start installation of replaceable components (a head, the camshaft or assembly of yokes).

Installation

 PERFORMANCE ORDER

1. Carefully clear the camshaft, beds of its bearings in a head of cylinders and covers, and also yokes of the drive of valves. Try to remove completely the slightest traces of slime and dirt. For rubbing of components use only pure, неворсящуюся rags.

2. Grease cams and bearing necks of the camshaft with special assembly lubricant (see an accompanying illustration).


If not carefully to grease a shaft before installation, it can lead to serious damages of bearings and cams in the first seconds after start of the engine prior to normal circulation of oil.


3. Accurately lower the camshaft in a head of cylinders. Having used a face head of the corresponding size or a piece of a pipe of suitable diameter as a mandrel, put tore an epiploon to the regular place (the open party with the spring established in a groove inside).
4. Establish into place assembly of yokes (see Removal, check of a state and installation of assembly of yokes).
5. Having turned a shaft as appropriate, put on its forward pin a cogwheel (marking of "UP" for 12 hours).
6. Install a belt of the GRM drive and the accompanying components (see Removal, check of a state and installation of a gas-distributing belt and cogwheels of the GRM drive).

If in the course of service of a head the provision of a bent shaft was brought down, take care at installation of a belt of alignment of adjusting tags of its cogwheel (see Removal, check of a state and installation of a gas-distributing belt and cogwheels of the GRM drive).


7. Turn out spark plugs and turn a bent shaft manually, checking correctness of installation of phases of gas distribution. Through two turns adjusting tags of gear have to return to a starting position. Otherwise take off a belt and achieve the required combination of tags.

If in the course of a provorachivaniye of a bent shaft there is resistance, the procedure should be stopped immediately!


8. Further installation is made as it should be, the return to an order of dismantle of components.