2.1.1. Head of cylinders

Head of cylinders from aluminum alloy, a saddle and plug-in directing plugs of valves.

Characteristic

Value

Height of a head of the block of cylinders, mm

M 115

  • nominal

84,8 — 85,0

  • minimum

83,8

M 102

  • nominal

98,5 — 98,4

  • minimum

97,8

M 123

  • nominal

84,8 — 85,0

  • minimum

84,0

M 110

  • nominal

93,9 — 94,0

  • minimum

93,1

Buckling of the plane of interface of a head to the block of cylinders in longitudinal/cross the directions, no more, than a mm

M 102

0,10

M 115

0,08

M 110

0,08

M 123

0,08


Main technical characteristics

Model

Diameter of the cylinder x piston stroke, mm
Working volume, cm 3
Rated power "net", kW (h.p.) / with a frequency of rotation of a bent shaft, rpm
The maximum torque, N. of m (кгс.м) / with a frequency of rotation of a bent shaft, rpm
Extent of compression

M 115.938

87x83,6

1997

70 (94)/4800

158 (16,1)/3000

9

M 102.920

89x80,25

1997

74 (100)/5500

160 (16,3)/3000

8

M 102.939

89x80,25

1997

80 (109)/5100

172 (17,5)/3500

9

M 102.980 *

95,5x80,25

2299

100 (136)/5100

205 (20,9)/3500

9

M 102.982 *

95,5x80,25

2299

92 (125)/5000

194 (19,8)/3500

8

M 115.954

93,75x83,6

2307

80 (109)/4800

185 (18,9)/3000

8

M 123.920

86x72,45

2525

74 (100)/5200

183 (18,7)/3000

8,4

M 123.921

86x72,45

2525

103 (140)/5500

196 (20,0)/3500

9,4

M 110.923

86x78,8

2746

115 (156)/5500

226 (23,0)/4000

9

M 110.984

86x78,8

2746

125 (170)/5500

224 (22,8)/4500

8

M 110.988

86x78,8

2746

136 (185)/6000

240 (24,5)/4500

9

* Engines of models M 102.980 and M 102.982 have an identical factory index (M 102.E23) and differ with extent of compression and a grade of the applied fuel.


Longitudinal section of the engine M 102


Cross-section of the engine M 102


Valves

Characteristic

Value

Diameter of valves of the engine, mm

M 102.985

  • inlet

41,0

  • final

37,0

Roughness of the plane of interface of a head to the block of cylinders, micron

M 102

0,005 — 0,020

M 115

0,012 — 0,020

M 110

0,012 — 0,020

M 123

0,012 — 0,020

Length of bolts of fastening of a head of cylinders, mm

M 102

  • nominal

119,0

  • maximum

122,0

M 115

  • nominal

119,0

  • maximum

122,0

M 110

  • nominal

160,0

  • maximum

162,7

M 123

  • nominal

160,0

  • maximum

162,7


Saddles of valves

Saddles of valves plug-in.

Characteristic

Value

Facet corner, hail.

45 +0 —15 0

Corner of the top cone, hail.

30

Corner of the lower cone, hail.

60

Width of a working facet, mm

M 102

  • inlet valves

1,8 — 2,5

  • final valves

1,5 — 2,5

M 115

  • inlet valves

2,0 — 2,1

  • final valves

1,5 — 2,5

M 110

  • inlet valves

2,3 — 2,5

  • final valves

1,5 — 2,5

M 123

  • inlet valves

2,3 — 2,5

  • final valves

1,5 — 2,5

When using unleaded gasoline it is necessary to establish stronger saddles of valves.


Characteristic of saddles of valves

Saddles of inlet valves

Size, mm

Engine model
M 115.938
M 102.920, M 102.939
M 102.980, M 102.982
M 115.954
Diameter of nests of saddles of valves

nominal

48,500 — 48,516

46,000 — 46,016

46,000 — 46,016

48,500 — 48,516

repair size (no more)

49,000

47,000

49,000

Outer diameter turned gray

nominal

48,590 — 48,600

46,090 — 46,100

48,590 — 48,600

repair size (no more)

49,80

47,30

49,0800

Internal diameter turned gray

 

37,0

Saddle height

 

10,29 — 10,40

7,980 — 8,000

10,89 — 11,00

Tightness at a press fitting of saddles of inlet and final valves

 

0,08 — 0,10

0,074 — 0,10

0,08 — 0,10

Size, mm
M 123.920, M 123.921
M 110.923
M 110.984, M 110.988
Diameter of nests of saddles of valves

nominal

42,700 — 42,716

47,000 — 47,016

47,000 — 47,016

repair size (no more)

43,700

48,018

Outer diameter turned gray

nominal

42,790 — 42,800

47,090 — 47,100

repair size (no more)

44,0

48,30

Internal diameter turned gray
 

 
Saddle height
 

10,89 — 11,00

8,51 — 8,6

 
Tightness at a press fitting of saddles of inlet and final valves
 

0,08 — 0,10

 


The directing plugs of valves

The directing plugs of valves plug-in, pressed in a head of cylinders.

Characteristic

Value

Tightness, mm

0,012 — 0,013

Effort of a press fitting, кгс.м

300,0 — 350,0


Characteristics of the directing plugs of valves

Parameter, mm

The directing plugs of inlet valves
nominal size
1st repair size
2nd repair size

Color of a tag

Gray-green

Red

White

Gray

Gray-brown

Outer diameter

14,03 — 14,05

14,21 — 14,23

14,41 — 14,43

Internal diameter

9,00 — 9,015

Diameter of an opening in the directing plug

14,02

14,20 — 14,22

14,40 — 14,42

Length

55,0

Extreme wear

9,025

Parameter, mm

The directing plugs of final valves
nominal size
1st repair size
2nd repair size

Color of a tag

Gray-green

Red

White

Gray

Gray-brown

Outer diameter

15,03 — 15,05

15,21 — 15,23

15,41 — 15,43

Internal diameter

11,000 — 11,018

Diameter of an opening in the directing plug

15,02

15,20 — 15,22

15,40 — 15,42

Length

45,0

Extreme wear

11,030