Engine Does Not Crank
Use this procedure in order to troubleshoot an engine that does not crank.
- Switches
- Batteries
- Electric starting system (if equipped)
- Flywheel ring gear
- Driven equipment
- Hydraulic cylinder lock
- Worn engine components
Show/hide table
| Troubleshooting Test Steps | Values | Results |
|---|---|---|
1. Inspect the Switches A. Check the keyswitch input to the ECM. B. Check engine shutdown switches. C. Connect Cat® Electronic Technician (ET) to the service tool connector. D. Use Cat ET to verify the status of the following parameters: - Shutdown switches |
Switches |
Result: The switches are OK. Proceed to Test Step 2. Result: A switch is NOT OK. Repair: Repair or replace damaged switch. If the problem is not resolved, proceed to Test Step 2. |
2. Inspect the Batteries A. Charge the batteries, if necessary. Refer to Special Instruction, SEHS7633, "Battery Test Procedure" for additional information. B. Load-test the batteries. Refer to Special Instruction, SEHS9249, "Use of 4C-4911 Battery Load Tester for 6, 8 V and 12 V Lead Acid Batteries" for additional information. |
Batteries |
Result: The batteries are OK. Proceed to Test Step 3. Result: The batteries are NOT OK. Repair: Repair or replace the batteries. If the problem is not resolved, proceed to Test Step 3. |
3. Check the Electric Starting System A. If the application is equipped with an electric starting system, perform the following procedure: a. Check the wiring to the starting motor solenoid. Refer to the electrical schematic. b. Check the engine start switch and the engine start relay for electrical power. c. Check the starting motor cables. If the starting motor cables are corroded, remove the starting motor cables and clean the starting motor cables. d. Test the operation of the starting motors. |
Starter |
Result: The electric starter is OK. Proceed to Test Step 6. Result: The electric starter is NOT OK. Repair: Repair or replace damaged electric starter. If the problem is not resolved, proceed to Test Step 6. |
4. Inspect the Flywheel Ring Gear for Damage |
Ring Gear |
Result: The flywheel ring gear is OK. Proceed to Test Step 5. Result: The flywheel ring gear is NOT OK. Repair: Repair or replace the ring gear. If the problem is not resolved, proceed to Test Step 5. |
5. Inspect the Driven Equipment |
Driven Equipment |
Result: The driven equipment is OK. Proceed to Test Step 6. Result: The driven equipment is NOT OK. Repair: Repair or replace damaged driven equipment. If the problem is not resolved, proceed to Test Step 6. |
6. Check for Hydraulic Cylinder Lock A. If an injector has been replaced, evacuate any fluids from the cylinder and attempt to start the engine. Fuel will flow from the cylinder head into the cylinders when a unit injector is removed. B. If the engine will not start, check for fluid in the cylinders (hydraulic cylinder lock) by removing the individual unit injectors. Check for damaged seals. Determine the type of fluid that locked up the cylinder. C. If there was a coolant leak, determine the cause of the leak. D. If there was excessive fuel in the cylinder, replace the seals and reinstall the injector. Drain any excess fuel from the cylinder head. |
Hydraulic Cylinder Lock |
Result: The engine does not have a hydraulic cylinder lock. Proceed to Test Step 7. Result: The engine has a hydraulic cylinder lock. Repair: Perform the necessary repairs. If the problem is not resolved, proceed to Test Step 7. |
7. Inspect the Engine for Internal Problems A. If a mechanical problem is suspected, disassemble the engine. Refer to the Disassembly and Assembly manual for additional information. B. Inspect the internal components for the following conditions: - Seizure - Broken components - Bent components |
Damaged or Worn Engine Components |
Result: There are worn or damaged engine components. Repair: Repair or replace the worn or damaged engine components. Verify that the repair eliminated the problem. |
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