Bomag BW 156 D-3 Service Manual page 39

Diesel engine
The new single drum rollers of product range BW 156/179 D-3/PD-3 are powered by Cummins diesel
engines of series B. This automotive engine is characterized by the following features:
• low weight,
• compact design,
• low specific fuel consumption,
• low noise development,
• low exhaust emissions,
• simple, but effective constructive design with simple installation characteristics.
The engines used in these single drum rollers have the following designations:
• BW 156 D-3/PD-3
• BW 179 D-3/PD-3
The engine 4B3.9 is an aspirating engine with a power of 56 kW.
The engine 4BT3.9, in contrast, is fitted with a turbo charger and has a power of 75 kW.
The 4-cylinder four stroke engines are water cooled.
The combustion method with direct fuel injection enables the use of a less expensive casting for the
cylinder head, highest possible utilization of fuel and minimum heat transfer to the coolant.
This in turn enables the use of more effective, quieter cooling fans and smaller, but more effective
radiators.
The extremely economical fuel consumption was achieved by the following design measures:
• small exhaust channels with minimum cooling,
• as a measure to improve the rate of efficiency the combustion chambers were specially shaped for
direct fuel injection,
• excellent mixing of fuel and air due to the helical flow out of the intake channel,
• alloyed trough head shaped pendulum shaft pistons,
• specially formed exhaust manifold for effective utilization of exhaust pulses in the turbo charger.
BW 156/177 D-3/PD-3
BW 178/179 D-3/PD-3
4B3.9
4BT3.9
Service Training
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