07-15-2025, 01:10 PM
Starting Issue Overview
A user faced persistent starting problems with a CAT 345 BL excavator. The machine refused to start reliably, whether cold in the morning or after running and being shut down warm. This caused downtime and frustration on the job site.
Symptoms Noticed
The excavator would crank but fail to fire up. Sometimes, it would start after excessive cranking but then struggle to keep running. No specific error codes were reported on the monitor.
Initial Checks
Basic checks included verifying battery condition, making sure the starter motor turned the engine at the right speed, and confirming there was enough fuel in the tank with no signs of fuel contamination.
Fuel System Focus
Most troubleshooting focused on the fuel system. The owner checked:
Possible Injector Problems
Attention turned to the injectors themselves. Worn or leaking injectors can cause hard starting or rough idle. Some contributors suggested performing a cylinder cut-out test or inspecting injectors for leakage overnight, which can drain pressure and make starting difficult.
Electrical and Sensor Checks
The owner also checked key sensors, such as the coolant temperature sensor and fuel pressure sensor. Faulty readings can confuse the ECU, causing improper fuel delivery at startup. Connections and grounds were cleaned to eliminate poor contacts.
Next Steps
Suggestions included:
The case highlighted how troubleshooting a CAT 345 BL starting issue often revolves around the fuel system, electrical sensors, and injector condition. Careful step-by-step checks help isolate the cause, preventing unnecessary part replacement and downtime.
A user faced persistent starting problems with a CAT 345 BL excavator. The machine refused to start reliably, whether cold in the morning or after running and being shut down warm. This caused downtime and frustration on the job site.
Symptoms Noticed
The excavator would crank but fail to fire up. Sometimes, it would start after excessive cranking but then struggle to keep running. No specific error codes were reported on the monitor.
Initial Checks
Basic checks included verifying battery condition, making sure the starter motor turned the engine at the right speed, and confirming there was enough fuel in the tank with no signs of fuel contamination.
Fuel System Focus
Most troubleshooting focused on the fuel system. The owner checked:
- Fuel filters for clogs or water.
- Fuel lines for air leaks.
- Fuel pump performance to ensure the injectors received proper pressure.
Possible Injector Problems
Attention turned to the injectors themselves. Worn or leaking injectors can cause hard starting or rough idle. Some contributors suggested performing a cylinder cut-out test or inspecting injectors for leakage overnight, which can drain pressure and make starting difficult.
Electrical and Sensor Checks
The owner also checked key sensors, such as the coolant temperature sensor and fuel pressure sensor. Faulty readings can confuse the ECU, causing improper fuel delivery at startup. Connections and grounds were cleaned to eliminate poor contacts.
Next Steps
Suggestions included:
- Checking the fuel shutoff solenoid for sticking.
- Testing fuel rail pressure during cranking.
- Considering a full injector bench test.
- Inspecting the glow plug or intake heater system, which can aid cold starts.
The case highlighted how troubleshooting a CAT 345 BL starting issue often revolves around the fuel system, electrical sensors, and injector condition. Careful step-by-step checks help isolate the cause, preventing unnecessary part replacement and downtime.
