The engine consists of a crankshaft and gas distribution mechanisms, as well as cooling, lubrication, power and control, start-up systems

With the help of a crank mechanism, the reciprocating movement of the pistons in the cylinders is converted into rotational movement of the crankshaft.

KAMAZ-740.10 engine cross section

The gas distribution mechanism opens and closes the valves in a timely manner, which let air into the cylinders and release exhaust gases from the cylinders.

KAMAZ-740.10 engine longitudinal section

The cooling system maintains the required thermal conditions of the engine.

The lubrication system supplies oil to the rubbing parts of the engine to reduce friction and wear.

The power system cleans and supplies air and fuel to the cylinders, and with the help of the regulator automatically regulates the flow (supply) of fuel to the combustion chamber depending on the engine load.

Diesel start system is required to rotate the crankshaft during start-up.

Here we describe a set of components of the KamAZ-740.10, KamAZ-7403.10 and KamAZ-7409.10 engines, explain the scheme of operation and the principle of operation of their mechanisms and systems.

The KAMAZ-740.10 engine (Fig. 1) is a four-stroke liquid-cooled diesel engine with a V-shaped arrangement of eight cylinders; is the base for all engine modifications of the brand.

The KamA3 - 7403.10 engine (Fig. 2) has increased power due to the use of gas turbine supercharging, in which part of the exhaust gas energy is used to compress air and force it into the cylinders.

KAMAZ-74003.10 turbocharged engine

Gas-diesel 7409.10 (Fig. 3) can operate both on natural gas ignited by a pilot dose of diesel fuel, and on diesel fuel in diesel mode.

KAMAZ-74009.10 gas-diesel engine

The main design data and parameters of the engines are given in the technical specification (in parentheses are the values ​​when the engine is running in diesel mode).

Technical characteristics of KamAZ engines

Model 740.10

  • Number of bars 4
  • Number of cylinders 8

V-shaped cylinder arrangement, 90° camber

Cylinder order 1-5-4-2-6-3-7-8

The direction of rotation of the crankshaft is right-hand

Cylinder diameter and piston stroke 120x120 mm

Displacement 10.85 l

Compression ratio 17

Rated power 154 kW

Maximum torque 637 Nm

Crankshaft speed, rpm:

  • - nominal 2600
  • - at maximum torque (1600-1800)
  • - at idle, minimum, no more than 600
  • - the same, maximum, no more than 2930

Intake valve timing:

  • - opening 13° to east. m.t.
  • - closing 49° a.m. m.t.

Same, inlet valve:

  • - opening 66° BC. m.t.
  • - close 10° after c. m.t.

Oil pressure in a warm engine, kPa:

  • - at rated speed 400-550
  • - at minimum idle speed, not less than 100

Nozzle model 33-01

High pressure fuel pump model 33-02

Model 7403.10

Number of bars 4

Number of cylinders 8

V-shaped cylinder arrangement, 90° camber

Cylinder order 1-5-4-2-6-3-7-8

The direction of rotation of the crankshaft is right

Cylinder diameter and piston stroke 120x120 mm

Displacement 10.85 l

Compression ratio 16

Rated power, kW 191

Maximum torque, Nm 785

Crankshaft speed, rpm:

  • - Nominal 2600
  • - at maximum torque 1600-1800
  • - at idle, minimum, no more than 600
  • - the same, maximum, no more than 2930

Intake valve timing:

  • - Opening 13° to east. m.t.
  • - closing 49° a.m. m.t.

Same, vp ear valve:

  • - opening 66° BC. m.t.
  • - close 10° after c. m.t.

Oil pressure in a warm engine, kPa:

  • - at rated speed 400-550
  • - at minimum idle speed, not less than 100

Nozzle model 271

High pressure fuel pump model 334

Model 7409.10

Number of bars 4

Number of cylinders 8

V-shaped cylinder arrangement, 90° camber

Cylinder order 1-5-4-2-6-3-7-8

The direction of rotation of the crankshaft is right

Cylinder diameter and piston stroke, mm 120x120

Displacement, l 10.85

Compression ratio 17

Rated power, kW 154

Maximum torque, Nm 637

Crankshaft speed, rpm:

  • - nominal 2550 (2600)
  • - at maximum torque 1300-1800
  • - at idle, minimum, no more than 600
  • - the same, maximum, no more than 2930

Intake valve timing:

  • - opening 13° to east. m.t.
  • - closing 49° a.m. m.t.

Same, inlet valve:

  • - opening 66° BC. m.t.
  • - close 10° after c. m.t.

Oil pressure in a warm engine, kPa:

  • - at rated speed 400-550
  • - at minimum idle speed, not less than 100

Nozzle model 33-01

High pressure fuel pump model 335