C175 Petroleum Engine Caterpillar

Crankcase Pressure Is High

Usage:

Use this procedure to troubleshoot a high crankcase pressure or use this procedure if one of the following diagnostic codes is active.

Show/hide table

Table 1
J1939 Code and Description	CDL Code and Description	Comments
101-0 Engine Crankcase Pressure : High - most severe (3)	E1036 (3) High Crankcase Pressure	The Engine Control Module (ECM) activates this code when the crankcase pressure has exceeded the limit for a programmed time period. The amber warning lamp is illuminated. The code is logged. Engine power is derated. This code can be caused by an obstructed tube, an obstructed breather, or an obstructed hose. Also, a plugged OCV system will cause the code.
101-15 Engine Crankcase Pressure : High - least severe (1)	E1036 (1) High Crankcase Pressure	The Engine Control Module (ECM) activates this code when the crankcase pressure has exceeded the limit for a programmed time period. The amber warning lamp is illuminated. The code is logged. Engine power is derated. This code can be caused by an obstructed tube, an obstructed breather, or an obstructed hose. Also, a plugged OCV system will cause the code.
101-16 Engine Crankcase Pressure : High - moderate severity (2)	E1036 (2) High Crankcase Pressure	The ECM activates this code when the crankcase pressure has exceeded the limit for a programmed time period. The amber warning lamp is illuminated. The code is logged. Engine power is severely derated. This code can be caused by an obstructed tube, an obstructed breather, or an obstructed hose. Also, a plugged OCV system will cause the code.

Probable Causes

Engine oil level
Faulty sensor
Lack of boost supply pressure
OCV system plugging
Internal engine problem
Drain line check valve
Separator

Recommended Actions

Show/hide table

Table 2
Troubleshooting Test Steps	Values	Results
1. Check the Engine Oil Level A. Check the engine oil level.	Engine oil level	Result: The engine oil level is OK. Proceed to Test Step 2. Result: The engine oil level is high. Troubleshoot the cause of the incorrect oil level.
2. Faulty Sensor A. Connect Caterpillar Electronic Technician (ET) to the service tool connector. B.Apply electrical power to the engine. Do not start the engine. C. Remove the oil filler cap. D. Monitor the crankcase pressure in Cat ET.	Crankcase pressure sensor	Result: The crankcase pressure reading is 0 kpa (0 inH2O) ± .5 kpa (2 inH2O). Proceed to Test Step 3. Result: The crankcase pressure reading is not 0 kpa (0 inH2O) ± .5 kpa (2 inH2O). Replace the crankcase pressure sensor.
3. Lack of Boost Supply Pressure A. Connect Caterpillar Electronic Technician (ET) to the service tool connector. B. Start the Engine. C. Inspect the boost line from the separator back to the intake manifold to ensure that there are no air leaks. D. Monitor the Inlet Manifold Air Pressure (IMAP) sensor reading in CAT ET to ensure that boost pressure is present.	Boost supply pressure	Result: The line is damaged or a leak is found. Replace the damaged line, or repair the leak Result: No boost pressure or boost is low. - Check the air inlet and exhaust system for leaks. - Check the operating conditions of the engine to ensure that the engine is not operating at low load and speed conditions. - Check the condition of the turbochargers Result: Boost pressure is ok Proceed to Test Step 4.
4. OCV System Plugging A. Remove electrical power from the engine. B. Check the OCV piping for plugging and/or freezing. C. Inspect the OCV tubing from the valve covers to the separator. D. Inspect the drain tubing from the separator to atmosphere.	Plugged OCV	Result: The OCV piping is plugged. Clean any obstructions from the tube. Result: The OCV piping is not plugged. Proceed to Test Step 5.
5. Internal Engine Problem Damaged pistons or rings can cause too much pressure in the crankcase. This condition will cause the engine to run rough. There will be more than the normal quantity of fumes (blowby) entering the OCV system. The OCV system can then more quickly become restricted, causing oil leakage at gaskets and seals that would not normally have leakage. Blowby can also be caused by worn valve guides or by a failed turbocharger seal. A. To determine whether the piston rings leak, measure the crankcase blowby. Use the following service tools, along with Software License, NETG5044: 1. 285-0901 Blowby Tool Gp (LARGE ENGINE) 2. 348-5430 Multi-Tool Gp	Damaged or worn engine parts	Result: Crankcase Blowby is high, and there are worn or damaged engine parts Repair or replace the worn or damaged parts. Result: Crankcase Blowby is OK. Proceed to next step
6. Drain Line Check Valve Malfunctioning A malfunctioning drain line check valve will allow oil and pressure to back up in the crankcase separator. Inspect the oil drain tube where it vents to atmosphere for signs of oil, smoke, and/or mist being emitted from the tube.	Check valve	Result: Oil or smoke is being emitted from the oil drain tube. Repair: Replace the drain line check valve. If the problem has not been resolved. Proceed to the next step.
7. Faulty Separator A. If all other Steps in this procedure have been followed and the crankcase pressure remains high, then replace the separator.	Separator	Result: The separator has been replaced Verify that the problem has been resolved.

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).