With the advent of downsized engines
and a demand for better engine performance, engine manufacturers
are turning to turbochargers to accomplish this.
A turbocharger is simply a centrifugal
compressor driven by exhaust gams. It consists of two rotors
connected by a common shaft. One rotor, called a turbine,
is located in the exhaust stream. The other compressor rotor
is placed on the engine's intake system.
The engines exhaust gases acting on
the turbine spins the rotors. When the compressor wheel reaches
sufficient R.P.M. it forces air into the cylinders in increased
volume not possible at atmospheric pressure. The presence
of more air in the cylinders allows more complete burning
of the fuel, increasing output.
 Turbocharged
engines, because they are more efficient, have areas that
require special attention. Two of these areas are important
to Hastings Manufacturing Company. Piston rings and oil filters
are critical parts of a turbocharged engine.
Turbocharged engines have combustion
pressures that are higher than naturally aspirated engines.
Cylinder and oil temperatures are also higher. It is necessary
to manufacture top compression rings from some type of high
strength iron. Regular piston ring iron will not stand up
to the rigorous demands of the turbocharged engine, and it
is likely they would break. A ring set which had been designed
for a naturally aspirated engine should never be substituted
in a turbocharged engine,
In the more efficient turbocharged
engine, higher exhaust temperatures will be observed. Engine
oil is used to both lubricate and cool the turbocharger bearings.
For the reason, the oil is a critical item. Most oil companies
have developed oils which we specially formulated for turbocharged
engines. These oils have high temperature additive, which
minimize oil coking on the bearings after the engine is shut
down. Oil and filters must be changed strictly according to
engine manufacturer's recommendations, as clean oil with proper
additives is even more critical in a turbo unit.
In summary, the turbocharger s high
R.P.M. operation (up to 200,000 R.P.M.) and elevated temperatures
(up to 1500- F) make it important to select proper engine
oils and follow engine manufacturer's recommended oil and
filter change intervals.
TURBOCHARGER SCHEMATIC
(P49)
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