COUPLING-INNER 3202927 - Caterpillar

Illustration 3 g01943813
Right side view of a C18 with two turbochargers in a series
(1) Low-pressure turbocharger
(2) High-pressure turbocharger
(3) PrecoolerSome applications of the C18 will have two turbochargers. The C18 arranges the two turbochargers in series. The two turbochargers allow the engine to have boost over the entire engine rpm range. The use of two turbochargers increases the maximum boost pressure to 410 kPa (60 psi). The engine also uses an air-to-air aftercooler (ATAAC).The Electronic Unit Injector system (EUI) eliminates many of the mechanical components that are traditionally used in the fuel injector assembly. The EUI also provides increased control of the timing and increased control of the fuel air mixture. The timing advance is achieved by precise control of the fuel injection timing. Engine speed is controlled by adjusting the injection duration.The ECM monitors the system. The ECM detects problems with the system. In the event of a system component failure, the operator is alerted to the condition by a red stop lamp. The check engine light is located on the dashboard. An electronic service tool can be used to read the numerical code of the faulty component or condition.Starting the Engine
The Electronic Control Module (ECM) will automatically provide the correct amount of fuel that is necessary to start the engine. The throttle should not be held while the engine is being cranked. If the engine fails to start in 30 seconds, the starter switch should be released. The starting motor should be allowed to cool for 2 minutes before being used again.
Excessive ether (starting fluid) can cause piston and ring damage. Use ether for cold weather starting purposes only.
Cold Mode Operation
Starting the engine and operation in cold weather is dependent on the type of fuel used, the oil viscosity, and other optional starting aids. For more information, refer to the Operation and Maintenance Manual, "Cold Weather Operation".The Cold Mode flag in Caterpillar Electronic Technician (ET) indicates that the engine system is compensating with a cold mode strategy.Some examples of a cold mode strategy may include:
Elevated RPM
Timing enhancements
Fuel injection enhancementsTroubleshooting performance-related problems when the Cold Mode flag is active is not recommended.The Cold Mode flag will activate in the following conditions:
Coolant temperature is less than 35° C (95° F)
Coolant temperature is less than 75° C (167° F) and NRS gas temperature is less than 35° C (95° F)
Coolant temperature is less than 75° C (167° F) and NRS gas temperature is less than 65° C (149° F)Once coolant temperature is above 75° C (167° F) and NRS gas temperature is greater than 65° C (149° F) for 10 minutes, no cold mode strategy will be active.Delayed Engine Shutdown (If Equipped)
The "Delayed Engine Shutdown" strategy allows the engine to run for a time after the engine start switch key is turned to the OFF position to cool the engine and system components. The engine start switch key may be removed.Note: There may be regulations that define the requirements for the operator and/or support personnel to be present when the engine