1-- 5
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1.3 ENGINE
The engine is a vertical, in--line four cylinder diesel
engine, which is direct--connected to the alternating
current generator. Information on the major engine
systems is provided in the following subparagraphs.
1.3.1 Electronic Governor Module
The electronic governor module is a solid state control
module preprogrammed for 1800 RPM. The electronic
governor module, along with the engine speed sensor ,
replaced the manual governor in order to provide a
constant engine speed.
1.3.2 Engine Air System
The air cleaner (Item 11, Figure 1-1) is designed to
prolong engine life and performance by preventing dirt
and grit from entering the engineand causingexcessive
wear on all operating parts. In order for the air filter to
operate properly, the operator must regularly maintain
the air cleaner equipment in accordance with the
instructions provided within this document.
1.3.3 Lube Oil Filter Arrangement
The engine lubr icating oil filter ismounted inahorizontal
arrangement and shown in Figure 1-4.
1.3.4 Fuel System
The fuel system is fitted with an in--line pre--filter and a
fuel filter, which als oacts as a water separator. Thefilter
is also fitted with a heater. The fuel system is shown in
Figure 1-3.
1.4 ENGINE SCREW THREADS
All threads used on the engine are metric.
1
2
3
4
5
6
7
8
9
1. Fuel Tank
2. Fuel Supply Line
3. Inline Fuel Filter
4. Mechanical
Fuel Pump (Engine)
5. Fuel Filter and Water
Separator
6. Injection Pump
8. Fuel Bleed Va lve
7. Injector Nozzles
9. Fuel Return Line
Figure 1-3 Fuel System Diagram
1
2
3
4
1. Oil Filter (Primary)
2. Oil Pressure Sender
3. Oil Pressure Switch
4. Oil Pan
Figure 1-4 Lube Oil
1.5 ALTERNATING CURRENT GENERATOR
1.5.1 Principle of Operation
The Marathon Alternator Company (Lima) brushless
AC generator (see Figure 1-2, item 9) is a
self--regulated, rotating field synchronous unit. The
generator stator and exciter stator are combined in a
common housing. The gener ator field, exciter rotor, and
rotating rectifier assembly are mounted on a common
shaft. The output of the exciter rotor is applied to the
generator field winding through a rotating, full--wave
bridge, silicon rectifier unit.
All connections between t he exciter stator windings and
the generator stator windings are internal within the
stator housing. Only the output power leads are
connected at the terminal box, w hich islocated on topof
the generator.
1.5.2 Alternating Current Generator Diagram
Figure 1-5 shows the internal schematic diagram of the
generator, exciter, and rectifier unit. The generator is a
three--phase unit, andtheexciter stator and exciter rotor
also hav ethree--phase windings. Aportion of theexciter
stator windings is connected across a tap on the
generator stator winding. This exciter shunt winding
provides the generator field excitation power required
for thegenerator no--load voltage. Another por tionof the
exciter stator windings is connected in series with the
output of the generator and provides a compounding
excitation characteristic.
