0388273 JOHNSON CARBURETOR ASSEMBLY

Illustration 1 g01158700
Note: EGR is used on certain types of engines with an external governor. Examples include Cat PEEC and Woodward 3201A. Note: EGR activates when oil pressure exceeds 69 kPa (10 psi) which is the idle speed low oil pressure threshold. Note: EGR deactivates when oil pressure falls below 69 kPa (10 psi) which is the idle speed low oil pressure threshold.
The GSC+ receives an engine start signal. The signal will be one of three.
The operator turns the ECS to the Manual Start position.
The ECS is in the AUTO position and the remote initiate contacts (IC) close.
The ECS is in the AUTO position and a start command is sent by the optional Customer Communication Module (CCM).
Before the cycle crank sequence begins, the GSC+ checks the system. The GSC+ checks that no system faults are present. The GSC+ checks that all previous shutdown faults have been reset. Note that shutdown faults are removed by turning the ECS to OFF/RESETposition. The GSC+ checks that the engine is not already running. The GSC+ also checks in order to make sure that the "Service" mode is not activated.
At the start of a crank cycle, the GSC+ checks the setpoint value for the crank time delay. If the setpoint value for the crank time delay is greater than zero seconds (factory default is five seconds), then following the setpoint value amount, the GSC+ will:
Activate the ignition shutoff relay (ISR). This disables ignition in the EIS control.
Deactivate the Fuel Control relay (FCR) on the ETR fuel systems.
Activate the starter motor relay (SMR). At the start of a crank cycle, the relay status indicators on the GSC+ display the status of K4 (SMR), K5 (RR), and K6 (ISR). K1 (EGR) may also be shown if the engine oil pressure is above setpoint value P014. If the setpoint value for the crank time delay is either zero seconds or the programmed amount of time has expired, the GSC+ will perform the following functions:
Deactivate the ignition shutoff relay (ISR) which enables ignition in the EIS control.
Activate the fuel control relay (FCR) on the ETR fuel systems.The starting motor relay (SMR) remains active until the cycle crank time reaches the setpoint value P017 for total crank time or until the engine starts. The setpoint value that is provided by the factory for P017 is ten seconds of crank time and ten seconds of rest time. The relay status indicators on the GSC+ display the status of K4, K5, and K7 (FCR) during this portion of the crank cycle. K7 is for use in ETR fuel systems. K1 (EGR) may also be shown if engine oil pressure is above setpoint value P014.
The GSC+ deactivates the starting motor relay (SMR) and the GSC+ activates the crank termination relay (CTR) when the engine speed reaches the setpoint value P011 for crank terminate speed. The factory default of setpoint value P011 is 400 rpm.
The GSC+ activates the electronic governor relay (EGR) when the oil pressure reaches setpoint value P014. Setpoint value P014 is for low oil pressure at idle speed. The factory default of setpoint value P014 is 70 kPa (10 psi). The EGR signals the electronic governor (EG) in order to accelerate the engine to the rated speed. This happens if the machine is equipped with the EG. Note: The optional customer communication module (CCM) can remotely activate the EGR when the setpoint value for the oil pressure is exceeded. The optional customer communication module (CCM) can remotely deactivate the EGR when the setpoint value for the oil pressure is exceeded.
The GSC+ shows the following information.
Information for one or more phases on the upper display
Information for the power meter on the lower display
Information for the engine system on the lower display
The relay status of K1 (EGR), K3 (CTR), K5 (RR), and K7 (FCR) on the lower displayEngine Starting Sequence for engines with an GECM
The GSC+ receives an engine start signal. The signal will be one of three.
The operator turns the ECS to the Manual Start position.
The ECS is in the AUTO position and the remote initiate contacts (IC) close.
The ECS is in the AUTO position and a start command is sent by the optional Customer Communication Module (CCM) to the GSC+.
The GSC+ checks the system before sending a start signal to the GECM. The GSC+ checks that no system faults are present. The GSC+ checks that all previous shutdown faults have been reset. Note that shutdown faults are removed by turning the ECS to OFF/RESETposition. The GSC+ also checks that the engine is not already running.
The GSC+ activates the starter motor relay (SMR), the run relay (RR), and the electronic governor relay (EGR).
The normally closed contacts of the SMR open. This will turn off the optional battery charger.
The normally open contacts of the RR close. This provides battery power to the Woodward loadshare module (if present).
The normally open contacts of the EGR close. This provides a logic high input signal to the start input of the GECM.
The engine GECM controls the following operations: starter motors, crank duration, ignition and timing. Refer to Troubleshooting, RENR5979, "G3500C Engines" for a complete description of the starting sequence for the GECM.
The setpoint value of P017 (Total Crank Cycle Time) and P018 (Cycle Crank Time) will determine if the starter motor relay will be activated. P018 determines the amount of time that the SMR will be energized. P018 also determines the amount of time that the SMR will be de-energized between attempts to crank the engine. The setpoint value P017 and P018 must match the corresponding settings of the engine GECM. The crank cycle and the starter motor are controlled by the GECM, not the GSC+. The SMR of the GSC+ will behave as if the SMR were controlling the starter motor. If these setpoint values are not matched in the engine GECM, the GSC+ may initiate false diagnostics and false condition of events.
While the starting motor is cranking, the GSC+ shows the status of the relays on the relay status indicators of the lower