5004274 JOHNSON CARBURETOR ASSY., Port, 115

Table 1
Event Code
Description Conditions which Activate the Code System
Response
E841(1) Cyl #1 Exhaust Port Temp Deviating Low
E842(1) Cyl #2 Exhaust Port Temp Deviating Low
E843(1) Cyl #3 Exhaust Port Temp Deviating Low
E844(1) Cyl #4 Exhaust Port Temp Deviating Low
E845(1) Cyl #5 Exhaust Port Temp Deviating Low
E846(1) Cyl #6 Exhaust Port Temp Deviating Low
E847(1) Cyl #7 Exhaust Port Temp Deviating Low
E848(1) Cyl #8 Exhaust Port Temp Deviating Low
E849(1) Cyl #9 Exhaust Port Temp Deviating Low
E850(1) Cyl #10 Exhaust Port Temp Deviating Low
E851(1) Cyl #11 Exhaust Port Temp Deviating Low
E852(1) Cyl #12 Exhaust Port Temp Deviating Low
E853(1) Cyl #13 Exhaust Port Temp Deviating Low
E854(1) Cyl #14 Exhaust Port Temp Deviating Low
E855(1) Cyl #15 Exhaust Port Temp Deviating Low
E856(1) Cyl #16 Exhaust Port Temp Deviating Low
E857(1) Cyl #17 Exhaust Port Temp Deviating Low
E858(1) Cyl #18 Exhaust Port Temp Deviating Low
E859(1) Cyl #19 Exhaust Port Temp Deviating Low
E860(1) Cyl #20 Exhaust Port Temp Deviating Low The cylinder exhaust temperature is lower than the average temperature for all of the cylinders. The amount of deviation has exceeded the trip point for the programmed delay time. The code is logged.
The alarm output is activated.
Table 2
Event Code
Description Conditions which Activate the Code System
Response
E841(3) Cyl #1 Exhaust Port Temp Deviating Low
E842(3) Cyl #2 Exhaust Port Temp Deviating Low
E843(3) Cyl #3 Exhaust Port Temp Deviating Low
E844(3) Cyl #4 Exhaust Port Temp Deviating Low
E845(3) Cyl #5 Exhaust Port Temp Deviating Low
E846(3) Cyl #6 Exhaust Port Temp Deviating Low
E847(3) Cyl #7 Exhaust Port Temp Deviating Low
E848(3) Cyl #8 Exhaust Port Temp Deviating Low
E849(3) Cyl #9 Exhaust Port Temp Deviating Low
E850(3) Cyl #10 Exhaust Port Temp Deviating Low
E851(3) Cyl #11 Exhaust Port Temp Deviating Low
E852(3) Cyl #12 Exhaust Port Temp Deviating Low
E853(3) Cyl #13 Exhaust Port Temp Deviating Low
E854(3) Cyl #14 Exhaust Port Temp Deviating Low
E855(3) Cyl #15 Exhaust Port Temp Deviating Low
E856(3) Cyl #16 Exhaust Port Temp Deviating Low
E857(3) Cyl #17 Exhaust Port Temp Deviating Low
E858(3) Cyl #18 Exhaust Port Temp Deviating Low
E859(3) Cyl #19 Exhaust Port Temp Deviating Low
E860(3) Cyl #20 Exhaust Port Temp Deviating Low The cylinder exhaust temperature is lower than the average temperature for all of the cylinders. The amount of deviation has exceeded the trip point for the programmed delay time. The code is logged.
The shutdown output is activated.
The engine is shut down. Probable Causes
Software for the Integrated Temperature Sensing Module (ITSM)
Monitoring system parameters
Inlet air restriction
Operation with a light load
Faulty thermocouple
Insufficient ignition
Valve lash settings
Low cylinder compressionRecommended Actions
Software for the ITSM and Parameter Settings
Ensure that the latest version of software for the ITSM has been installed in the control module.Monitoring System Parameters
Ensure that the monitoring system parameters for the exhaust port temperatures are set correctly. Refer to Troubleshooting, "Event Codes" for information that relates to the default parameters, ranges, and delay times of the monitoring system parameters that are for the exhaust port temperatures.Inlet Air Restriction
Inlet air restriction can cause uneven exhaust port temperatures. Cylinders at the front half of the engine may have exhaust port temperatures that are lower than the exhaust port temperatures for the cylinders at the rear half of the engine by 10 to 20 °C (18 to 36 °F).Measure the inlet air restriction for each turbocharger. If an imbalance in the system is discovered, make repairs in order to equalize the inlet air restriction for each of the turbochargers.Ensure that the spark arrestors for each cylinder have not become restricted. Replace any spark arrestors that are damaged or obstructed. Operation with a Light Load
Operation with a low load can result in low exhaust temperatures. Operate the engine at low idle or near low idle in order to identify a misfire problem.Troubleshoot the cause of the misfire. Refer to Troubleshooting, "Engine Misfires, Runs Rough or Is Unstable".Faulty Thermocouples
Observe the temperatures from the thermocouples after the engine is shut off. If the engine is allowed to cool to ambient conditions, the thermocouples will report a temperature that is close to the ambient temperature.When the engine is operating properly, the temperatures from similar locations are reduced at a similar rate. Also, the temperatures from similar locations are comparable.If any discrepancies are found, switch the suspect thermocouple for another thermocouple. If the temperature problem follows the thermocouple, replace the suspect thermocouple.If the temperature problem stays at the original location of the suspect thermocouple, investigate the cause for the low temperature.Insufficient Ignition
Use Cat ET to check for logged diagnostic codes that relate to the ignition system. Troubleshoot the code. Refer to Troubleshooting, "Ignition Primary - Test".If no logged diagnostic codes are present for the suspect cylinder, inspect the components of the ignition system for the cylinder. Check the following components for problems:
Engine wiring
Ignition transformers
Spark plugsRefer to Troubleshooting, "Ignition Secondary - Test".Valve Lash Settings
Check the valve lash settings for the valves on the engine. Refer to Systems Operation/Testing and Adjusting, "Valve Lash and Valve Bridge Adjustment" for information that is related to adjusting the valve lash for the engine.Low Cylinder Compression
Measure the cylinder pressures of the suspect cylinders in order to check for problems that are related to compression.If low cylinder compression is found, investigate the cause of the low compression. Perform the necessary repairs.