4.7.4. Check and adjustment of gaps in the mechanism of the drive of valves
Warm up the engine up to the working temperature. Uncover a head of the block of cylinders (see above). Turn out spark plugs. Install the piston of the 1st cylinder in compression step VMT (the tag on a pulley of a bent shaft has to be opposite to a tag on the engine block).
Check by means of a set of probes gaps between cams of camshafts and adjusting washers in the drive of inlet valves of the 1st and 2nd cylinders, then final valves of the 1st and 3rd cylinders. Turn a bent shaft on one turn and again establish a tag on a pulley against a tag on the block of cylinders. In this provision of a bent shaft check gaps in the mechanism of the drive of inlet valves of the 3rd and 4th cylinders and final valves of the 2nd and 4th cylinders. Write down the measured gaps and compare them to the recommended gaps.
Nominal gap on the hot engine, mm:
for inlet valves 0,32 — 0,40
for final valves 0,37 — 0,45
If gaps deviate nominal, make adjustment.
Adjustment of gaps is made on the cold engine.
Adjusting washers which are issued from 2,00 to 2,98 mm thick through each 0,02 mm are applied to change of gaps.
Fig. 2.35. Replacement of an adjusting washer at adjustment of gaps in the mechanism of the drive of valves: And — compression of a pusher by means of Nissan RV 10115110 adaptation; B — installation of a clamp the Nissan RV 10115120 for blocking of a pusher in the drowned situation and extraction of an adjusting washer by means of a magnet
For replacement of adjusting washers use Nissan RV 10115110 and RV 10115120 devices (fig. 2.35)
. Turn a bent shaft and establish cams of the drive of valves of the adjustable cylinder up. Then squeeze special adaptation an adjustable pusher and take out a magnet an adjusting washer. Measure and write down washer thickness. Determine thickness of a washer which needs to be established on the following formula:
thickness of the established adjusting washer = thickness of the taken-out adjusting washer + the measured gap — a nominal gap.
Choose an adjusting washer which thickness corresponds to settlement size. If there is no washer of settlement thickness, use a washer thickness, the next to settlement.
Oil engine a new adjusting washer and establish it on a pusher by an inscription down. Take out the device for compression of a pusher. Make similarly adjustment of other valves. Again check gaps. Establish into place a cover of a head of the block of cylinders, previously having replaced its sealing laying.
Execute the remained assembly operations as it should be, the return to removal. Check operation of the engine.