3406C (PEEC III) Truck Engines Caterpillar

Introduction

Troubleshooting can be difficult. The troubleshooting index gives a list of possible problems. To make a repair to a problem, refer to the possible cause and the corrective action. Also, refer to Electronic Troubleshooting, SENR5503 for 3406C PEEC III.

This list of problems, causes and corrections will only give an indication of the location of a possible problem. This will also list the type of repairs that are needed. Normally, more other repair work is needed beyond the recommendations in the list.

Service personnel may remember similar complaints which were corrected by a previous method of troubleshooting. Although the complaint could be similar, the cause could be different.

Get a good description of the problem from the operator and/or the person that owns the vehicle. Knowing the details of the problem can save time. This will make the repair job faster and easier.

Troubleshooting Problems

Loud Combustion Noise

Probable Cause

1. Low Quality Fuel Or Water In The Fuel

   Refer to Special Instruction, SEHS7067, "Fuel Recommendations For Caterpillar Diesel Engines". Also, Special Instruction, SEHS6947 has fuel correction factors and tables.

2. Defective Fuel Injector Nozzle

   Remove the fuel injector nozzles. Refer to Testing and Adjusting, "Testing Fuel Injector Nozzles"for the correct testing procedure.

3. Defective Fuel Injection Pump

   Although a fuel injection pump may supply enough fuel, the pump could be the cause of rough running. The rough running could be the result of slow timing that is caused by wear on the bottom end of the plunger. Refer to Testing and Adjusting, "Checking Plungers and Lifters of an Injection Pump" for the correct specifications and procedures to check the plungers and lifters.

4. Incorrect Fuel Injection Timing

   Refer to Electronic Troubleshooting, SENR5503 for the correct test procedure.

5. Wrong Timing Position Sensor Calibration

   Refer to Electronic Troubleshooting, SENR5503 for the correct test procedure.

6. PEEC III System Component Fault

   Refer to Electronic Troubleshooting, SENR5503.

Fuel Consumption Too High

Note: Refer to Truck Performance Diagnostic Guide, SEBD0808, "Truck Performance Complaints" for additional information on related problems.

Probable Cause

1. Errors In The Measurement Of Miles Per Gallon

   Follow the truck high fuel consumption checklist.

   • Verify that the odometer is working correctly.

   • Fill the fuel tank. Correctly measure the amount of fuel that is added to the tank.

   • Comparison to other trucks

   • Different truck or engine specifications

   • Different operating loads

   • Different operating modes

2. Low quality fuel or water in the fuel

   Refer to Special Instruction, SEHS7067, "Fuel Recommendations For Caterpillar Diesel Engines". Also, Special Instruction, SEHS6947 has fuel correction factors and tables.

3. Fuel system leaks

   Inspect the fuel system for leaks. Make any needed repairs or replacements.

4. Excess Idle Time

   The engine should be shut off whenever the engine is not being used to supply power.

5. Excess Road Speed Or Operation At High Engine Speeds

   Reduce road speed and follow progressive shifting driving guidelines.

6. Excessive Wind Resistance

   Decrease the gap between the cab and the trailer. Add an air deflector to the truck.

7. Dragging Brakes

   Adjust or repair the brakes.

8. Fuel And Combustion Noise (knock)

   Check the items that are listed in the following problems:

   • "Too Much Black Smoke Or Gray Smoke"

   • "Engine Overheating"

   • "Engine Over Cooling"

   Refer to Electronic Troubleshooting, SENR5503.

9. Wrong fuel injection timing

   Refer to Electronic Troubleshooting, SENR5503 for the correct test procedure.

10. Wrong timing position sensor calibration

    Refer to Electronic Troubleshooting, SENR5503 for the correct test procedure.

11. Wrong Rack Position Sensor Calibration

    Refer to Electronic Troubleshooting, SENR5503 for the correct test procedure.

Too Much Black Smoke Or Gray Smoke

Probable Cause

1. Not Enough Air For Combustion

   Check for a plugged air cleaner element or for blockage in the air lines. Refer to Testing And Adjusting for the procedures to check inlet manifold pressure and aftercooler core leakage.

2. Defective fuel injection nozzle

   Remove the fuel injector nozzles. Refer to Testing and Adjusting, "Testing Fuel Injector Nozzles"for the correct testing procedure.

3. Wrong fuel injection timing

   Refer to Electronic Troubleshooting, SENR5503 for the correct test procedure.

4. Wrong timing position sensor calibration

   Refer to Electronic Troubleshooting, SENR5503 for the correct test procedure.

5. Incorrect Rack Position Sensor Calibration

   Refer to Electronic Troubleshooting, SENR5503 for the correct test procedure.

6. PEEC III system component fault

   Refer to Electronic Troubleshooting, SENR5503.

Too Much White Smoke or Blue Smoke

Probable Cause

1. Too Much Oil In The Engine

   Do not put too much oil in the crankcase. If the oil level in the crankcase increases during engine operation, check for fuel in the crankcase. Fuel can be eliminated from the crankcase by making repairs or replacements to the fuel injection lines and the nozzles.

2. Engine Misfires

   Refer to items that are listed in "Too Much Black Smoke Or Gray Smoke". Refer to Electronic Troubleshooting, SENR5503 for more information.

3. Rough Running Engine

   Refer to items that are listed in "Too Much Black Smoke Or Gray Smoke". Refer to Electronic Troubleshooting, SENR5503 for more information.

4. Incorrect fuel injection timing

   Refer to Electronic Troubleshooting, SENR5503 for the correct test procedure.

5. Incorrect timing position sensor calibration

   Refer to Electronic Troubleshooting, SENR5503 for the correct test procedure.

6. Coolant In The Combustion System

   Coolant in the combustion chamber can cause white smoke. A cracked cylinder head, a cracked cylinder liner, or a bad cylinder head gasket are possible causes for this condition.

7. Failed Turbocharger Oil Seal

   Check the inlet manifold and the aftercooler core for oil. Make any needed repair or replacement of the turbocharger.

8. Worn Valve Guides

   Refer to Specifications, SENR5507 for the correct specifications for the valve guide.

9. Worn Piston Rings

   Worn piston rings and/or cylinder walls can be the cause of blue smoke. Worn piston rings and/or cylinder walls can cause a loss of compression. Make a visual inspection of the cylinder walls and the piston rings. If necessary, measure the cylinder walls and piston rings. Refer to Specifications, SENR5507 for the specifications.

   Note: High wear at low mileage is normally caused by dirt that enters the engine through the air inlet.

The Engine Has Low Oil Pressure.

Probable Cause

1. Low Engine Oil Level

   Check the engine oil level and fill to the proper level.

2. Oil Leaks

   Check for a loose oil filter or for loose oil supply lines.

3. Dirty Oil Filter Or Cooler Core

   Check the operation of the bypass valve for the filter. As required, install new oil filter elements. Clean the oil cooler core or install a new oil cooler core. Remove the dirty oil and fill the engine with clean oil to the correct level.

4. Diesel Fuel In Lubricating Oil

   Find the location of the diesel fuel leak that allows the fuel to enter the lubrication oil. Make repairs, as needed. Remove any oil that contains diesel fuel. Install new oil filters and fill the engine with clean oil to the correct level.

5. Too Much Clearance Between Rocker Arm Shaft And Rocker Arms

   Check for the correct lubrication in the valve train. Install new parts, as needed.

6. Defect In The Oil Pump Suction Pipe

   Replacement of the pipe is needed.

7. Faulty Relief Valve For The Oil Pump

   Clean the valve and the housing. Install new parts, as required.

8. Defective Oil Pump

   Make a repair or a replacement of the oil pump, as needed.

9. Too Much Clearance Between Camshaft And Camshaft Bearings

   Inspect the camshaft and the camshaft bearings. Make any needed repairs or replacements.

10. Too Much Clearance Between Crankshaft And Crankshaft Bearings

    Inspect the bearings and the crankshaft journals. Make a repair or a replacement, as needed.

11. Too Much Bearing Clearance For Idler Gear

    Inspect the bearings and make replacements, as needed.

12. No Piston Cooling Jets

    Install the piston cooling jets.

13. Defective Oil Pressure Gauge

    Replace the oil pressure gauge.

14. PEEC III system component fault

    Refer to Electronic Troubleshooting, SENR5503.

Engine Overheating

Probable Cause

1. Low Coolant Level

   A sufficient amount of coolant will not go through the engine and the radiator if the coolant level is too low. This lack of coolant will not take enough heat from the engine. There will be insufficient radiator coolant flow. The heat will not be released into the cooling air. Low coolant level is caused by leaks or the wrong filling of the radiator. Once the engine has cooled, make sure that the coolant can be seen at the low end of the radiator filler neck that is on the radiator top tank.

2. Defective Temperature Gauge

   A temperature gauge which does not work correctly will not show the correct temperature. A temperature gauge can show that the coolant temperature is too hot. This can happen even when other conditions are normal. Install a gauge that is working order or check the cooling system with the 4C-6500 Digital Thermometer .

3. Dirty Radiator

   Check the radiator for debris between the fins of the radiator core which prevents free air flow through the radiator core. Check the radiator for the following items. These items prevent the free flow of coolant through the radiator.

   • Debris

   • Dirt

   • Deposits on the inside of the radiator core

4. Loose Belts

   A loose fan drive belt will cause a reduction in air flow through the radiator. Tighten the belts according to the Belt Tension Chart that is shown within this module.

5. Defective Hoses

   Defective hoses with leaks can normally be seen. Hoses that have no visual leaks can collapse during operation. This will cause a restriction in the flow of coolant. Hoses become soft and/or get cracks after a period of time. Refer to Operation and Maintenance Manual for the frequency for changing hoses. The inside of the hose can become loose, and the loose particles can cause a restriction in the flow of coolant.

6. Shunt Line Restriction

   A restriction of the shunt line from the radiator top tank to the engine water pump will cause a reduction in the water pump efficiency. A shunt line that is not correctly installed will also cause a reduction in the water pump efficiency. The result will be low coolant flow and overheating.

7. Improperly Operating Shutters

   Check the opening temperature of the shutters. The shutters must be completely closed at a temperature below the fully open temperature of the water temperature regulators. Also verify that the fan control switches or the viscous fans are operating correctly.

8. Defective Water Temperature Regulator (Thermostat)

   Above normal heating can be caused by a regulator that does not open or a regulator that opens part of the way. Refer to Testing And Adjusting for the procedure to test the water temperature regulators.

9. Defective Water Pump

   A water pump with a loose impeller does not pump enough coolant for correct engine cooling. A loose impeller can be found by removing the water pump. If the impeller has no damage, check the impeller clearance. The clearance between the impeller and the housing is 0.56 mm to 1.50 mm (0.022 inch to 0.059 inch).

   To check for a loose impeller, use the following procedure:

   1. Push the shaft in one direction.

   2. Pull the shaft in the other direction.

   3. Excessive movement indicates that the impeller is loose. Make any needed repairs or replacements to the water pump.

10. Air In Cooling System

    Air can enter the cooling system in different ways. The most common causes are the following causes.

    • Filling the cooling system incorrectly

    • Combustion gas that leaks into the system

    Combustion gas can enter the system through internal cracks or bad cylinder head gaskets. Air in the cooling system causes a reduction in coolant flow and bubbles in the coolant. Air bubbles hold coolant away from engine parts. This will prevent heat flow. Air in the cooling system can be found by the BOTTLE TEST. The test is made by using the following equipment.

    • A one pint bottle

    • A bucket of water

    • A hose that will fit the end of the overflow pipe of the radiator

    The cooling system should be filled correctly before testing. Use a wire to hold the relief valve in the radiator cap open. Install the radiator cap and tighten the radiator cap. Place the hose over the end of the overflow pipe. Start the engine. Operate the engine at high idle rpm for a minimum of five minutes after the engine is at normal operating temperature. Use a cover on the radiator core to keep the engine at operating temperature. After five minutes at operating temperature, place the loose end of the hose in the bottle that is filled with water. Put the bottle in the bucket of water. Make sure that the bottle is turned upside-down. If the bottle is empty in less than forty seconds, too much exhaust gas is leaking into the cooling system. Locate the source of the air or the gas that is leaking into the cooling system and correct, as needed.

11. Wrong Fan, Incorrect Fan Position Or Incorrect Fan Shroud Position

    A reduction or a loss of air flow through the radiator can be caused by a wrong fan, a fan in the wrong position or a shroud in the wrong position. The fan must be large enough to send air through most of the area of the radiator core. Make sure that the fan size, the fan shroud, and the position of the fan and shroud are according to the recommendations of the Truck Manufacturer.

12. Incorrect Radiator Size

    The area of a small radiator is not large enough to release heat into the cooling air. This will cause the engine to run at higher than normal temperatures. Make sure that the size of the radiator is according to the recommendations of the Truck Manufacturer.

13. Not Enough Air Flow Through Radiator Because Of Restriction In Engine Compartment

    The air flow through the radiator comes out of the engine compartment. Make sure that the engine accessories are not preventing the free flow of air through the engine compartment.

14. High Outside Temperature

    The outside temperature can be too high for the rating of the cooling system. There is not enough temperature difference between the outside air and the coolant temperature. To receive better cooling, use the vehicle in a lower gear.

15. Operating At High Altitude

    The cooling capacity of the cooling system goes down as the truck is used at higher altitudes. A pressurized system that is large enough to keep the coolant from boiling must be used.

16. Engine Lugging

    Lugging causes the engine rpm and the fan rpm to be low. The load on the engine causes the engine to lug when the vehicle is used in a gear that is too high for the engine rpm. The engine rpm will not increase even though the accelerator pedal is pushed down. Lugging also occurs when the vehicle is used in a gear and the engine rpm goes down with the accelerator pedal at maximum travel. This low rpm causes a reduction in air flow through the radiator. This also causes a reduction in the flow of coolant through the system. The combination of less air and less coolant flow during the high input of fuel will cause above normal heating of the engine.

17. Air Inlet Restriction

    Higher cylinder temperatures can be caused by a restriction of the air that is coming into the engine. Heat that is an above normal amount must be transferred to the cooling system. A restriction can be checked with a water manometer or a vacuum gauge (inches of water). Connect the gauge to the engine air inlet between the air cleaner and the inlet to the turbocharger. Install the gauge. Run the engine at full load rpm and check the restriction. The maximum restriction of the air inlet is 635 mm (25 inch) of water. If the indication is higher than the maximum permissible restriction, remove the dirt from the filter element or install a new filter element. Recheck the restriction. If the indication is still higher than the maximum permissible restriction, there must be a restriction in the air inlet piping.

18. Exhaust Restriction

    A restriction in the exhaust system causes high cylinder temperatures. Heat that is an above normal amount must be transferred to the cooling system. Check for damage to piping or for a bad muffler. If no damage is found, check the system for back pressure from the exhaust (the pressure difference measurement between the exhaust outlet and the atmosphere). The back pressure must not be more than 1016 mm (40 inch) of water. The system can also be checked by removing the exhaust pipes from the exhaust manifolds. Remove the exhaust pipes. Start and run the engine. Check if the problem has been corrected.

19. Incorrect Fuel Injection Timing

    Refer to Testing And Adjusting for checking and making the necessary adjustments to the fuel injection timing.

20. Transmission Problems

    Power shift transmissions or automatic transmissions that are cooled by the engine cooling system can cause abnormal heating. This happens if the transmission is out of adjustment or not working correctly. See the transmission Service Manual for the correct adjustments.

Overcooling The Engine

Probable Cause

1. Long Idle Periods

   When the engine is running with no load, only a small quantity of fuel is burned. Therefore, the heat from the engine is removed too fast.

2. Very Light Load

   Very light loads, a very slow speed or downhill travel can cause overcooling. These conditions cause the engine to only burn a small quantity of fuel. This results in less heat inside the cylinders. The installation of shutters helps to correct this condition.

3. Defective Water Temperature Regulator (thermostat)

   A regulator that is stuck open will cause overcooling. A thermostat that is partially stuck open can cause overcooling if the vehicle has a light load. Coolant that leaks around the thermostat can cause overcooling.

Coolant Leaks That Are Outside Of The Engine

Probable Cause

1. Leaks In Hoses Or Connections

   Check all hoses and connections for visual signs of leakage. If no leaks are seen, look for damage to hoses or loose clamps.

2. Leaks In The Radiator And/Or Expansion Tank

   Pressurize the radiator and/or the expansion tank with the 9S-8140 Pressurizing Pump. Check for leaks. Refer to Testing And Adjusting, "Testing Radiator And Cooling System For Leaks".

3. Leaks In The Heater

   Pressurize the radiator and/or the expansion tank with the 9S-8140 Pressurizing Pump. Check for leaks. Refer to Testing And Adjusting, "Testing Radiator And Cooling System For Leaks".

4. Leaks In The Water Pump

   Check the water pump for leaks before starting the engine. Start the engine and look for leaks. If the water pump leaks, repair the water pump or install a new water pump.

5. Cylinder Head Gasket Leakage

   Look for leaks along the surface of the cylinder head gasket. Install a new head gasket if leaks are visible.

Coolant Leaks At The Overflow Tube

Probable Cause

1. Defective Pressure Cap Or Relief Valve

   Check the sealing surfaces of the pressure cap and the radiator. Make sure that the cap is sealing correctly. Check the opening pressure and the sealing ability of the pressure cap or the relief valve with the 9S-8140 Pressurizing Pump. Check for leaks. Refer to Testing And Adjusting, "Testing Radiator And Cooling System For Leaks".

2. Engine Temperature That Is Too High

   A coolant temperature that is too high will cause the pressure to increase beyond the pressure capabilities of the cap. This will cause a coolant loss through the overflow tube. Refer to "Engine Overheating".

3. Problems With The Expansion Tank

   The expansion tank can be part of the radiator or the expansion tank can be installed separately from the radiator. The expansion tank must be large enough to hold the expansion of the coolant as the coolant gets warm. The expansion tank must be large enough to hold the expansion of the coolant during sudden pressure changes in the cooling system. Make sure that the expansion tank is installed correctly. Make sure that the expansion tank is the correct size according to the recommendations of the Truck Manufacturer.

4. Cylinder Head Gasket Leakage Or Crack(s) In Cylinder Head Or Cylinder Block

   While the engine is running, remove the radiator cap. Look for air bubbles in the coolant. Bubbles in the coolant are a sign of probable leakage at the head gasket. Remove the cylinder head from the engine. Check the cylinder head, the cylinder walls and the head gasket surface of the cylinder block for cracks. When the head is installed, use a new head gasket, a spacer plate gasket, water seals, and O-ring seals.

Coolant Leakage Inside Engine

Probable Cause

1. Cylinder Head Gasket Leakage

   If the cylinder head gasket leaks between a water passage and an opening into the crankcase, coolant will get into the crankcase.

2. Crack(s) In Cylinder Head

   Cracks can be in the following areas:

   • upper surface of the cylinder head

   • area between a water passage and an opening into the crankcase

   These cracks can allow coolant to get into the crankcase.

3. Crack(s) In Cylinder Block

   Cracks in the cylinder block between a water passage and the crankcase will allow coolant to get into the crankcase.

Fuel In Crankcase Oil

Probable Cause

1. Loose Inner Fuel Injection Line Nut(s)

   A loose fuel injection line nut or a defective O-ring seal on the end of the adapter inside the cylinder head can cause fuel leakage into the crankcase. Check for a defective O-ring seal and tighten the nuts. Torque the nuts to 40 ± 7 N·m (30 ± 5 lb ft).

2. Fuel Nozzle Leaks

   A loose purging screw will cause fuel dilution in the crankcase. A leaking purging screw washer will cause fuel dilution in the crankcase. Check for defective purging screw washers. Tighten the purging screws to 2 ± 1 N·m (20 ± 7 lb in).

   Note: Whenever the purging screws are loosened or removed, the washer must be replaced in order to help prevent leakage.