Dimensions of the swirl chamber seat in the cylinder head
Valve seat dimensions
The cylinder head is cast iron and features plug-in valve seats and swirl combustion chambers. The camshaft bearing seats are made directly in the material of the cylinder head.
| Camshaft bearing bore diameters: | |
| - nominal: | 30.500 - 30.525 mm; |
| - repair: | 30.575 - 30.600 mm. |
| Pusher socket hole diameters: | |
| - nominal: | 35.000 - 35.030 mm; |
| - repair: | 35.500 - 35.530 mm. |
| Valve guide bore diameters: | |
| - nominal: | 8.000 - 8.035 mm; |
| - repair: | 8.263 - 8.288 mm. |
| Diameters of nests of vortex combustion chambers (see fig. Dimensions of the swirl chamber seat in the cylinder head): | |
| - nominal: | |
| size A: | 31.250 - 31.280 mm; |
| size B: | 27.530 - 27.560 mm; |
| - repair: | |
| size A: | 31.550 - 31.580 mm; |
| size B: | 27.830 - 27.960 mm. |
| Height of nests of vortex combustion chambers C (see fig. Dimensions of the swirl chamber seat in the cylinder head): | |
| – nominal: | 4.983 - 5.034 mm; |
| - repair: | 5.223 - 5.284 mm. |
Cylinder head gasket
The thickness of the cylinder head gasket is selected depending on the protrusion of the pistons above the upper plane of the cylinder block, and the value of the most protruding piston is taken into account.
The gasket thickness is identified by the corresponding designation:
- for cylinder blocks with nominal cylinder diameters: the gasket has cutouts;
- for cylinder blocks with overhaul cylinder diameters (0.5 or 1.0): the gasket has a hole.
Designation of cylinder head gaskets
Piston protrusion (mm) | Designation of the head gasket on the cylinder block with cylinder diameters | |
nominal | repair | |
0,500 – 0,680 | 2 cutouts | 2 holes |
0,681 – 0,740 | 3 cutouts | 3 holes |
0,741– 0,840 | 4 cutouts | 4 holes |
Installation method: Cylinder head gasket installed by inscription "OBEN-TOP" towards the head (the inscription must be visible after the gasket is installed on the cylinder block).
Combustion chambers
Swirl combustion chambers, steel, inserted into the cylinder head and fixed with a steel ball.
Chamber type: vortex Ricardo Comet Mark V.
The protrusion of the combustion chambers from the lower plane of the cylinder head: 0–0.061 mm.
Valve seats
The valve seats are pressed into the cylinder head.
Valve seat dimensions
| Size (mm) in accordance with fig. Valve seat dimensions | Valve seat | |
inlet | graduation | |
| Nominal diameter: | ||
A | 38,00 – 38,03 | 33, 00 – 33,03 |
IN | 8,3 – 8,5 | 8,8 – 9,0 |
| 1. repair diameter: | ||
A | 38,20 – 38,03 | 33,20 – 33,23 |
IN | 8,6 – 8,8 | 9,1 – 9,3 |
| 2. repair diameter: | ||
A | 38,40 – 38, 43 | 33,40 – 33,43 |
IN | 8,9 – 9,1 | 9,4 – 9,6 |
Valve springs
The springs are the same for both intake and exhaust valves. Free length: 43 mm.
Valves
Valves installed in the cylinder head are actuated by camshaft lobes through cylindrical tappets.
Valve sizes
| Kind of size | Valve | |
inlet | high school graduation | |
| Rod diameter: | ||
| - nominal | 7,82 – 7,97 | 7,81 – 7,96 |
| – 1. repair | 8,02 – 8,17 | 8,01 – 8,16 |
| – 2. repair | 8,22 – 8,37 | 8,21 – 8,36 |
| Plate diameter | 36,40 – 36,60 | 31,90 – 32,10 |
| Valve length | 107,05 – 107,15 | 109,15 – 109,25 |
Valve clearance (cold)
Inlet valve clearance: 0.35±0.05 mm.
Exhaust valve clearance: 0.50±0.05 mm.
Valve clearance adjustment: by selecting the thickness of the adjusting plates located in the recess of the pushers.
Adjustment plate thickness range: 3.00–4.75 mm.
Difference in thickness of adjusting plates: 0.05 mm.
Pushers
Outside diameter:
- nominal: 34.950–34.975 mm;
- repair: 35.450–35.475 mm.
Visitor comments