HARNESS AS-CEM 3805465 - Caterpillar

Probable Causes
Active or logged codes
Engine oil level
Failed turbocharger seals
Worn valve guide seals or faulty valve guide seals
Worn valve guides
Worn piston rings
Extended idle timesRecommended Actions
Note: Replacing the DOC and DPF is recommended if there is oil in the exhaust.
Table 1
Troubleshooting Test Steps Values Results
1. Check for Active or Logged Diagnostic Codes
A. Establish communication between Caterpillar Electronic Technician (ET) and the Electronic Control Module (ECM). Refer to Troubleshooting, Electronic Service Tools, if necessary.
B. Download the "Product Status Report" from the engine ECM before performing any troubleshooting or clearing diagnostic trouble codes.
Note: Troubleshoot any active codes before continuing with this procedure.
Diagnostic Codes
Result: Active codes are present.
Troubleshoot the active code.
Result:No active codes are present.
Proceed to Test Step 2.
2. Check Engine Oil Level and Obtain an Oil Sample
A. Check oil level and obtain an oil sample. If the oil level is high, then take an oil sample to check for fuel dilution. Refer to Troubleshooting, Oil Contains Fuel if fuel is present.
Oil
Result: The engine oil sample shows moitor or action required.
Make necessary repairs
Result: The engine oil sample and oil level are OK.
Result: The engine oil level is not at the correct level.
Determine root cause of why the oil level was high or low.
3. Failed Turbocharger Seals
A. Check the inlet manifold and the exhaust manifold for oil.
Turbo Seals
Result: Oil is present in the inlet or exhaust manifold.
Repair: Replace the turbocharger. Verify the repair.
Result: Oil is not present in the inlet or exhaust manifold.
Proceed to Test Step 4.
4. Worn Valve Guide Seals or Faulty Valve Guide Seals
A. Inspect the valve guide seals for wear and for damage.
Valve Guide Seals
Result: The valve guide seals are damaged.
Repair: Replace the valve guide seals. Verify the repair.
Result: The valve guide seals are not damaged.
Proceed to Test Step 5.
5. Worn Valve Guides
A. Inspect the valve guides for wear. Refer to the Specification manual for the maximum permissible wear of the valve guides.
Valve Guides
Result: The valve guides are worn.
Repair: If necessary, recondition the cylinder head. Verify the repair.
Result: The valve guides are not worn.
Proceed to Test Step 6.
6. Worn Piston Rings
A. Piston rings that have excessive wear can cause too much pressure in the crankcase. The additional pressure in the crankcase will cause more than the normal amount of crankcase blowby from the crankcase breather. Use the following service tools, along with Software License, NETG5044:
1. 285-0900 Blowby Tool Gp (SMALL ENGINE)
2. 348-5430 Multi-Tool Gp
B. Inspect piston rings
Piston Rings
Result The piston rings are worn.
Repair: Replace the piston rings. Verify the repair.
Result The piston rings are not worn.
Proceed to Test Step 7.
5. Extended Idle Times
A. Extended idle times will allow oil to pass into the exhaust system.
Idle Times
Result The idle times are extensive.
Repair: Reduce the idle times.
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).