Check and adjustment
Examination
If camshafts or valve-related components are removed or replaced, or if engine performance becomes abnormal over time due to changes in valve clearances, check as follows:
1. Start the engine and warm it up.
2. Stop the engine.
3. Remove the valve cover. See below.
4. Remove the mudguard from the right wing protective trim.
5. Measure valve clearances as follows:
A. Set the piston of cylinder No. 1 to TDC on the compression stroke.
- Rotate the crankshaft pulley clockwise and align the TDC mark with the timing indicator on the front cover.
- At the same time, make sure that the cam lobes of the intake and exhaust camshafts of cylinder No. 1 are facing away from each other, as shown in the figure.
- Otherwise, turn the crankshaft pulley one more turn (360°) and arrange them as shown in the picture.
b. Using a feeler gauge, measure the valve clearances between the valve lifters and the camshaft.
Valve clearances. See section below «Technical data and specifications».
- Guided by the figure, use a feeler gauge to measure the valve clearances in the places marked with a mark «X», as indicated in table No. 1 below (in Fig.) places are marked with black arrows.
- The piston of cylinder No. 1 is at TDC during the compression stroke
With. Turn the crankshaft pulley one revolution (360°) clockwise, align the TDC mark with the timing indicator on the front cover.
- Using a feeler gauge, using the drawing as a guide, measure the valve clearances in the marked places «X», as shown in table No. 2 below (in Fig. places are marked with black arrows).
- The piston of cylinder No. 4 is at TDC on the compression stroke.
Table No. 1
Measurement location | Cylinder No. 1 | Cylinder No. 2 | Cylinder No. 3 | Cylinder No. 4 | |
The piston of cylinder No. 1 is at TDC during the compression stroke | Inlet | X | X | ||
Issue | X | X |
Table No. 2
Measurement location | Cylinder No. 1 | Cylinder No. 2 | Cylinder No. 3 | Cylinder No. 4 | |
The piston of cylinder No. 4 is at TDC during the compression stroke | Inlet | X | X | ||
Issue | X | X |
6. If the measured value differs from the norm, make an adjustment. See below.
Adjustment
Make adjustments based on the selected valve tappet thickness.
1. Remove the camshafts. See above.
2. Remove valve tappets whose clearances differ from the norm.
3. Using a micrometer, measure the thickness at the center of the removed valve tappets (A).
4. Calculate the thickness of the replacement valve tappet using the following formula.
Calculation of valve tappet thickness
t = t1 + (C1 - C2), Where:
- t = Thickness of replacement valve tappet.
- t1 = Thickness of the removed valve tappet.
- C1 = Measured valve clearance.
- C2 = Standard valve clearance.
Intake 0.28mm
Release 0.30 mm
- Thickness of the new valve tappet (IN) can be identified by the markings (A), embossed on the reverse side (inside the cylinder)
Marking «788» means thickness 7.88mm
Note. Valve tappets are available in 26 thicknesses ranging from 7.88 to 3.38 mm in 0.02 mm increments (during production at the factory).
5. Install the selected valve tappets.
6. Install the camshafts. See above.
7. Turn the crankshaft pulley by hand several turns.
8. Using standard values, make sure that the valve clearances on a cold engine are within normal limits. See above.
9. Install the remaining components in the reverse order of removal.
10. Warm up the engine and check for unusual noise or vibration.