BOLT 7X0434 - Caterpillar

Introduction
For Specifications with illustrations, make reference to Engine Specifications For G379, G398 & G399 Engines, Form No. REG01306. If the Specifications in Form REG01306 are not the same as in the Systems Operation and the Testing and Adjusting, look at the printing date on the back cover of each book. Use the Specifications given in the book with the latest date.Engine Design
G379 Engine
Arrangement and number of cylinders ... V8Bore ... 158.8 mm (6.25 in.)Stroke ... 203.2 mm (8.00 in.)Direction of Rotation (when seen from flywheel end). SAE Standard Rotation ... CounterclockwiseSAE Opposite Rotation ... ClockwiseFiring Order (Injection Sequence). SAE Standard Rotation ... 1-8-5-4-7-2-3-6SAE Opposite Rotation ... 1-4-5-2-7-6-3-8G398 Engine
Arrangement and number of cylinders ... V12Bore ... 158.8 mm (6.25 in.)Stroke ... 203.2 mm (8.00 in.)Direction of Rotation (when seen from flywheel end). SAE Standard Rotation ... CounterclockwiseSAE Opposite Rotation ... ClockwiseFiring Order (Injection Sequence). SAE Standard Rotation ... 1-12-9-4-5-8-11-2-3-10-7-6SAE Opposite Rotation ... 1-4-9-8-5-2-11-10-3-6-7-12G399 Engine
Arrangement and number of cylinders ... V16Bore ... 158.8 mm (6.25 in.)Stroke ... 203.2 mm (8.00 in.)Direction of Rotation (when seen from flywheel end). SAE Standard Rotation ... CounterclockwiseSAE Opposite Rotation ... ClockwiseFiring Order (Injection Sequence). SAE Standard Rotation ... 1-2-11-12-3-4-9-10-15-16-5-6-13-14-7-8SAE Opposite Rotation ... 1-12-11-4-3-10-9-16-15-6-5-14-13-8-7-2Ignition System
The ignition system has five basic components a magneto, (two on earlier G399 Engines) ignition transformers for each cylinder, wiring harness, spark plugs and instrument panel.
Component Location (G399 Engine Illustrated)
(1) Ignition transformer. (2) Spark plug. (3) Wiring harness. (4) Solid state magneto. (5) Magneto drive housing. (6) Timing bolt.Magneto Operation (Fairbanks Morse)
Cutaway View Of Solid State Magneto (Fairbanks Morse) (Typical Illustration)
(1) Timing bolt. (2) Pulser coil assembly. (3) Plate and power board assembly. (4) Distribution board. (5) Capacitor. (6) Alternator housing. (7) Pulser coil (trigger circuit). (8) Pulser rotor. (9) Electronic switch (silicon controlled rectifier). (10) Plug connector.The magneto is a solid state type. It generates (makes) current in the alternator section of the magneto. Low tension current is held in the capacitor and then released. Distribution is then made through the distribution board (4). This system has no contact points, contactors or brushes. There is no spark inside the magneto and only minimum wear. An ignition spark of high tension is made by the transformer to start the air fuel mixture burning under all operating conditions.The alternator makes a voltage as the magnet rotor is turned by the engine through a drive coupling. The alternating current is sent through a rectifier and held in a capacitor (5). A zener diode, on the power board is the regulator of the capacitor voltage for proper ignition.As the pulser rotor (8) moves by each pulser coil (trigger circuit) (7), a voltage is made and sent to the electronic switch (silicon controlled rectifier) (9) for the cylinder ready for ignition. The switch is then turned on and permits the capacitor (5) to release the voltage (discharge). Then the voltage goes through the distribution