CONE-SPECIAL TAPERED 1262729 - Caterpillar

Refer to Systems Operation, Testing, and Adjusting for additional information on determining the cause of this condition.Probable Causes
Engine supports
Driven equipment
Low compression (cylinder pressure)
Electronic unit injectors
Individual malfunctioning cylinderRecommended Actions
Note: Complete the procedure in the order in which the steps are listed.
Table 1
Troubleshooting Test Steps Values Results
1. Engine Supports
A. Inspect the mounts and the brackets while you run the engine through the speed range. Look for mounts and brackets that are loose and/or broken.
B. Check the alignment of the following before operating the engine under load for any length of time:
Mounts
Coupling
Engine supports
Result: The mounts and brackets are loose and/or broken.
Repair: Replace the mounts and brackets that are loose and/or broken.
Result: The mounts and brackets are not loose and/or broken.
Proceed to Test Step 2.
2. Driven Equipment
A. Inspect the mounting bolts for the driven equipment. Inspect the alignment and the balance of the driven equipment.
B. Inspect the coupling.
Driven equipment
Result The driven equipment and the alignment are not OK.
Repair: Repair or replace the driven equipment.
Result: The driven equipment and the alignment are OK.
Proceed to Test Step 3.
3. Low Compression (Cylinder Pressure)
A. Perform a compression test. Refer to Systems Operation, Testing, and Adjusting, "Compression - Test ".
Low compression
Result: Low compression is recorded on one or more cylinders.
Repair: Possible causes of low compression are shown in the following list:
Loose glow plugs
Faulty piston
Faulty piston rings
Worn cylinder bores
Worn valves
Faulty cylinder head gasket
Damaged cylinder head
Make any repairs, as necessary.
Result: No faults found.
Proceed to Test Step 4.
4. Electronic Unit Injectors
A. Use the electronic service tool to check for active diagnostic codes that relate to the electronic unit injectors.
Diagnostic codes
Result: There are active diagnostic codes for the fuel injectors
Repair: Troubleshoot the active diagnostic codes. Refer to Troubleshooting, "Diagnostic Trouble Codes"
Result: There are no active diagnostic codes for the fuel injectors.
Proceed to Test Step 5.
5. Individual Malfunctioning Cylinders
A. With the engine speed at a fast idle, use the electronic service tool to perform the manual "Cylinder Cut Out Test". As each cylinder is cut out, listen for a change in the sound from the engine. When a cylinder is cut out, there should be a noticeable change in the sound of the engine.
Cylinders
Result: There is not a noticeable change in the sound of the engine for at least one cylinder.
Repair: Investigate the cause of the fault on any cylinder that is not operating. Investigate the cause of the fault on any cylinder that is operating below normal performance.
Result: There is a noticeable change in the sound of the engine for each cylinder.
Contact the Dealer Solution Network (DSN).