Engine Will Not Crank

TM 9-2320-312-24-2

Troubleshooting Section

Driven Equipment

b. Load test the batteries. Refer to Special

Instruction, SEHS9249, "Use of 4C-4911

Battery Load Tester for 6, 8 and 12 Volt Lead

Check the alignment and balance of driven

Acid Batteries".

equipment.

2. Check the vehicle wiring to the starting motor

Engine Misfiring or Running Rough

solenoid. Refer to the OEM vehicle manual.

Refer to Troubleshooting, "Engine Misfires, Runs

3. Check the engine start switch and the relay for

Rough, or Is Unstable".

switch power.

4. Inspect the starting motor cables for damage

i01351154

or loose connections.

Engine Will Not Crank

5. If the starting motor cables are corroded, remove

SMCS Code: 7569

the starting motor cables and clean the starting

motor cables.

Probable Causes

6. Test starting motor operation.

Note: This is NOT an electronic system problem.

7. Inspect flywheel ring gear for damage.

Refer to Testing and Adjusting for additional

information.

8. Ensure free movement of the driveline.

The probable root causes are listed in order below:

9. Remove engine accessories that may lock up

the engine and inspect engine accessories that

Batteries

may lock up the engine.

Starting circuit

The following list illustrates examples of engine

accessories that may lock up the engine:

Starting motor solenoid

Air compressor

Starting motor

Power steering pump

Flywheel ring gear

Engine oil pump

Transmission

10. Check for fluid in the cylinders (hydraulic

PTO

cylinder lock) by removing the individual

hydraulic electronic unit injectors.

Engine accessory

Note: Drain the fuel from the cylinder head. Fuel will

Hydraulic cylinder lock

flow from the cylinder head into the cylinders when

the hydraulic electronic unit injector is removed.

Internal engine problem

11. Disassemble the engine. Inspect the internal

Ring gear

components for the following conditions:

Recommended Actions

Seizure

Perform the following diagnostic procedures in

Broken components

order:

Bent components

1. Inspect the batteries.

Refer to Disassembly and Assembly.

a. Charge the batteries. Refer to Special

Instruction, SEHS7633, "Battery Test

12. Inspect the flywheel ring gear for damage.

Procedure".

Refer to Disassembly and Assembly for more

information.