4.7.4. Check and adjustment of gaps in the mechanism of a drive of valves
Warm up the engine to working temperature. Uncover heads of the block of cylinders (see above). Turn out spark plugs. Establish the piston of the 1st cylinder in VMT of a step of compression (the label on a pulley of a cranked shaft should be opposite to a label on the engine block).
Check by means of a set щупов gaps between cams of camshafts and adjusting washers in a drive of inlet valves of the 1st and 2nd cylinders, then final valves of the 1st and 3rd cylinders. Turn a cranked shaft on one turn and again establish a label on a pulley against a label on the block of cylinders. In this provision of a cranked shaft check gaps in the mechanism of a 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 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 from nominal, make adjustment.
Adjustment of gaps is made on the cold engine.
Adjusting washers which are issued in the thickness from 2,00 to 2,98 mm 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 a drive of valves: And — pusher compression by means of the Nissan RV 10115110 adaptation; B — installation of a clamp of Nissan RV 10115120 for pusher blocking 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 adaptations (fig. 2.35)
. Turn a cranked shaft and establish cams of a drive of valves of the adjustable cylinder up. Then compress the special adaptation an adjustable pusher and take out a magnet an adjusting washer. Measure and write down thickness of a washer. Define thickness of a washer which it is necessary to establish on the following formula:
thickness of an established adjusting washer = thickness of the taken-out adjusting washer + the measured gap — a nominal gap.
Choose the adjusting washer which thickness corresponds to settlement size. If there is no washer of settlement thickness, use a washer in the thickness closest to the settlement.
Grease with engine oil a new adjusting washer and establish it on a pusher an inscription down. Take out the adaptation for pusher compression. 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.