C9.3 Marine Auxiliary and Generator Set Engine Caterpillar

Engine Does Not Crank

Usage:

C9.3 C93

Use this procedure to troubleshoot an engine that will not crank.

Complete the procedure in the order in which the steps are listed.

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Table 1
Troubleshooting Test Steps	Values	Results
1. Inspection of the Batteries and Battery Cables A. Inspect the main power switch, battery posts, and battery cables for loose connections and for corrosion. If the battery cables are corroded, remove the battery cables and clean the battery cables. Tighten any loose connections. B. Inspect the batteries. C. Charge the batteries. Refer to Special Instruction, SEHS7633, "Battery Test Procedure" for additional information. D. Load-test the batteries. Refer to Special Instruction, SEHS9249, "Use of 4C-4911 Battery Load Tester for 6 v, 8 v, and 12 v Lead Acid Batteries".	Batteries	Result The batteries and cables are OK. Proceed to Test Step 2. Result The batteries and cables are not OK. Repair: Make the necessary repairs. If the problem is not resolved, proceed to Test Step 2.
2. Switches and/or Circuit Breakers (if applicable) A. If equipped, check any switches and/or circuit breakers that may interfere with the engine cranking. Refer to the applications electrical schematic for additional information.	Switches and/or Circuit Breakers	Result The switches and/or circuit breakers are OK. Proceed to Test Step 3. Result The switches and/or circuit breakers are not OK. Repair: Make the necessary repairs. If the problem is not resolved, proceed to Test Step 3.
3. Starting Motor Solenoid and Starting Circuit Test the operation of the starting motor circuit. Refer to Systems Operation/Testing and Adjusting, "Electrical System" for additional information.	Starting Motor Solenoid and Circuit	Result The starting motor solenoid and circuit are OK. Proceed to Test Step 4. Result The starting motor solenoid and circuit are not OK. Repair: Make the necessary repairs. If the problem is not resolved, proceed to Test Step 4.
4. Inspect the Starter Pinion and Flywheel Ring Gear A. Test the operation of the starting motor. B. Check the pinion clearance. Inspect the pinion and the flywheel ring gear for damage. Refer to Systems Operation/Testing and Adjusting, "Electrical System" for additional information.	Starter Pinion and Flywheel Ring Gear	Result The starter pinion and flywheel ring gear are OK. Proceed to Test Step 5. Result The starter pinion and flywheel ring gear are not OK. Repair: Make the necessary repairs. If the problem is not resolved, proceed to Test Step 5.
5. Inspect Engine Accessories and the Transmission (if applicable) A. Ensure free movement of the driveline. B. Remove any engine accessories that may lock up the engine and inspect any engine accessories that may lock up the engine. The following list illustrates examples of engine accessories that may lock up the engine: 1. Hydraulic pump that is driven from the rear gear group 2. Air compressor 3. Engine oil pump 4. Other components that are driven by the engine	Engine Accessories and Transmission	Result The engine accessories and transmission are OK. Proceed to Test Step 6. Result The engine accessories and transmission are not OK. Repair: Make the necessary repairs. If the problem is not resolved, proceed to Test Step 6.
6. 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. Check the exhaust (NRS) cooler for leaks. Refer to Testing and Adjusting, "Exhaust Cooler (NRS) - Test". D. If there was excessive fuel in the cylinder, replace the seals and reinstall the injector. Drain any excess fuel from the cylinder head. E. If a mechanical problem is suspected, disassemble the engine. Refer to the Disassembly and Assembly manual. Inspect the internal components for the following conditions: 1. Seizure 2. Broken components 3. Bent components	Hydraulic Cylinder Lock	Result The engine has hydraulic cylinder lock. Repair: Make the necessary repairs. Verify that the repair eliminated the problem.

If the procedure did not correct the issue, contact your Cat dealer Technical Communicator (TC). For further assistance, your TC can confer with the Dealer Solutions Network (DSN).