Detroit Diesel Troubleshooting Diagrams

Loss of compression in Series 60 engines may result from a variety of sources, including worn or broken fire or compression rings, holes in pistons, leaky valves, scored or worn cylinder walls, leaky or broken gaskets and cracked cylinder heads or cylinder liners. The detection and elimination of the cause or causes of cylinder pressure losses is vital to engine life and efficient operation. To assist the mechanic in effectively measuring the loss of cylinder pressure, and locating the source of abnormal leaks in individual cylinders, the following test procedure has been developed. ‪

1. Move the vehicle requiring test to the chassis dynamometer; refer to OEM guidelines.
2. Disconnect air compressor;
3. Start the engine.
4. Run the engine and bring the engine coolant temperature to normal operating range.
5. Run vehicle to full load and rated speed.
6. Attach a manometer calibrated to read in. H ₂ O, to the oil dipstick opening.
7. Measure and record crankcase pressure.
8. Shut down engine.
9. Remove the vehicle from the chassis dynamometer.
10. Review the crankcase pressure test results.
    1. If the crankcase pressure was greater than 3 in. H ₂ O (.75 kPa);
    2. If the crankcase pressure was less than 3 in. H ₂ O (.75 kPa); perform a cylinder compression test.
11. Compare the cylinder compression test results to specifications.
    1. If cylinder pressure is below specifications
    2. If cylinder pressure is within specification, call Detroit Diesel Technical Service Group.

Worn or Damaged Valve or Cylinder Kit Repair

Perform the following steps for worn or damaged valve or cylinder kit: ‪

1. Remove cylinder head;
2. Inspect the cylinder head for worn or damaged valves; For repair and replacement procedures
3. Inspect the cylinder kit components for worn or damaged liners; pistons or piston rings;
4. Verification of repairs made to cylinder valve(s) or cylinder kit components is required;

Verification of Repair for Worn or Damaged Valve or Cylinder Kit

Perform the following steps to determine if the repaired valve or cylinder kit resolved the misfiring cylinder condition: ‪

1. Start the engine.
2. Run the engine speed up to the occurrence of the misfiring.
3. Listen for misfiring cylinder.
   1. If the engine is not misfiring, no further troubleshooting is required.
   2. If the engine is misfiring, call Detroit Diesel Technical Service Group.

To determine if a faulty electronic control module (ECM) is causing the cylinder to misfire, perform the following: ‪

Note: Carefully disengage the lock tab on the power harness and injector harness connectors when removing.

1. Remove the thru-bolts holding the ECM to the engine;
2. Remove the ECM from the engine and tag the ECM for core return.
3. Obtain a new reprogrammed ECM for the engine you are troubleshooting.
4. Inspect the ECM isolators for any damage. Replace if necessary,
5. Install the ECM to the engine using thru-bolts;
6. Torque the ECM thru-bolts to 23 – 27 N · m (17 – 20 lb · ft).
7. Torque the ECM connector hold-down screws to 24 – 30 N · m (21 – 26 lb · in.).

Faulty ECM Repair

No repair authorized for ECM. ‪

Verification of Repair for Faulty ECM

Perform the following steps to determine if the new ECM resolved the misfiring cylinder condition: ‪

1. Start the engine.
2. Run the engine speed up to the occurrence of the misfiring.
3. Listen for misfiring cylinder.
   1. If the engine is not misfiring, shut down the engine. No further troubleshooting is required.
   2. If the engine is misfiring, shut down the engine and check for worn or damaged valves and cylinder kits;

To determine if a faulty fuel injector is causing the cylinder to misfire, perform the following steps: ‪

1. Install DDL adaptor to the data cable and plug the adaptor into the DDL connector in the vehicle; refer to OEM guidelines.
2. Start the engine.
3. >From the DDEC III/IV Select Menu, scroll to select ENGINE and press the ENTER key.
4. Scroll to FUEL INJECTOR INFO (CUTOUT) and press the ENTER key.
5. Scroll to select NEW TEST and press the ENTER key.
6. Scroll to select RPM SETTING FOR CCO TEST NORMAL and scroll to select 1000 and press the ENTER key.
7. Scroll to select AUTO and press the ENTER key. Wait for END OF TEST.Note: If an injector cannot be cutout, you will see an ERROR message. Press FUNC to exit the cylinder cutout function, press the FUNC key.
8. Scroll the list to review the results of the cylinder cutout test. To find suspect injectors, look for a cylinder with a value that is within 0.2 degrees of the NO CUTOUT PULSE WIDTH, by comparing the CUTOUT PULSE WIDTH values to the NO CUTOUT PULSE WIDTH values.
   1. If any CUTOUT PULSE WIDTH values are within 0.2 degrees of the NO CUTOUT PULSE WIDTH, shut down the engine and refer to section .
   2. If any CUTOUT PULSE WIDTH values are not within 0.2 degrees of the NO CUTOUT PULSE WIDTH, shut down the engine.

Faulty Fuel Injector Repair

Perform the following steps for faulty fuel injector assembly(s): ‪

1. Remove and replace injector assembly(s) whose values are within 0.2 degrees of the NO CUTOUT PULSE WIDTH;
2. Verify replaced injector assembly(s), .

Verification of Repair for Faulty Fuel Injector

Perform the following steps to determine if the replaced fuel injector(s) resolved the misfiring cylinder condition: ‪

1. Refer to section for the exhaust caution before preceeding. Start the engine.
2. Run the engine speed up to the occurrence of the misfiring.
3. Listen for misfiring cylinder.
   1. If the engine is not misfiring, shut down the engine. No further troubleshooting is required.
   2. If the engine is misfiring, shut down the engine and check for a faulty electronic control module (ECM);

The injector height is adjusted using the injector height gage, J 39697 (DDEC III/IV) or J 35637-A (DDEC II and I). On engines equipped with a Jake Brake ® , move the handle on the injector height gage to the alternate position, 90 degrees to the shank. A height gage pilot hole is provided in the fuel injector body on the machined surface contacted by the injector clamp near the solenoid.

Note: Be sure the height gage seats on the machined surface with the tip in the pilot hole. Foreign material in the pilot hole or on the machined surface may prevent accurate setting of the injector height.

Intake valve clearance and injector height are adjusted by means of an adjusting set screw and locknut located at the valve (or injector) end of the rocker arm;

Note: On engines equipped with a Jake Brake ® , measure valve lash and injector height before removing any brake housings. Only remove the brake housings necessary to provide access for adjustment.

Perform the following steps to recalibrate improper injector setting: ‪

Note: Injector calibration and bar codes may be absent from the load plates on first-run production DDEC III/IV injectors 5235575, 5235580, and 5235550. The correct calibration code for these units is “01”. Load plates on current DDEC III/IV injectors include the required calibration or bar code information.

1. Scroll to select FUNCTION to return to the FUEL INJECTOR CAL menu on the DDR.
2. Scroll to select FUEL INJECTOR CAL. Select UPDATE and press the ENTER key.
3. Type the four-digit “Update Injector Calibration” password for the DDR and press the ENTER key. If this feature is not password protected, type “0000” and press the ENTER key.
4. A message will appear telling you to use the scroll keys to select the cylinder (requiring changes) or select TYPE # (enter the numerical keys to change the CAL (calibration value).Note: An asterisk (*) will highlight the first cylinder number on the list.
5. Scroll to the cylinder requiring change and type in the required two-digit injector calibration code number. Press the ENTER key.Note: The ENTER key must be pressed before the DDR will allow selection of another cylinder number.
6. Repeat step , until all changes have been made.
7. Scroll to select FUNCTION and press the ENTER key.
8. Scroll to select YES and press the ENTER key to reprogram the ECM with the revised injector calibration codes.Note: Turning the ignition to the off position and waiting five seconds before starting the engine is not required.
9. Disconnect the DDR; refer to OEM guidelines.

Verification of Repair for Improper Injector Setting

Perform the following steps to determine if the proper injector setting adjustment resolved the misfiring cylinder condition: ‪

1. Install the valve rocker cover(s)
2. Start the engine.
3. Run the engine at 1000 r/min.
4. Listen for misfiring cylinder.
   1. If the engine is not misfiring, no further troubleshooting is required. Shut down the engine.
   2. If the engine is misfiring, shut down the engine. Check for improper valve clearance and injector height and damaged or worn camshaft lobes and rollers;

To determine if an improper injector calibration setting is causing the cylinder to misfire, perform the following steps: ‪

1. Remove the valve rocker cover(s);
2. Record the injector calibration code of each injector noting the cylinder number;
3. Turn vehicle ignition to the on position , but do not run engine.
4. Install Display Data Line (DDL) adaptor to the data cable and plug the adaptor into the DDL connector in the vehicle; refer to OEM guidelines.
5. >From the Diagnostic Data Reader (DDR) DDEC III/IV Select Menu, scroll to select ENGINE and press the ENTER key.
6. Scroll to select FUEL INJECTOR INFO and press the ENTER key.
7. Scroll to select FUEL INJECTOR CAL and press the ENTER key.
8. Scroll to select FUEL INJECTOR CAL. Select VIEW and press the ENTER key.
9. Compare the calibration code(s) shown on the display with the two digit calibration code(s) on the injector(s).
   1. If the calibration code on the display is different then the calibration code on the suspect injector for that cylinder, the injector setting must be repaired.
   2. If test codes match; refer to section  Intake valve clearance

To determine if aerated fuel is causing the cylinder to misfire, perform the following steps: ‪

1. Disconnect the fuel line return hose from the fitting located at the fuel tank.
2. Place the opened end of fuel line into a suitable container.
3. Start the engine.
4. Run the engine at 1000 r/min.
5. Visually check to see if air bubbles are rising to the surface of the fuel within the container.
   1. If air bubbles are present.
   2. If air bubbles are not present, check for improper calibration setting; Shut down the engine.

Aerated Fuel Repair

Perform the following steps for air in fuel repair: ‪

1. Shut down engine.
2. Tighten all fuel line connections between fuel tank and fuel pump; refer to OEM guidelines.
3. Visually inspect all fuel lines between fuel tank and fuel pump for leaks.
4. Replace any damaged components;
5. Verify repair of fuel lines:
   1. If no air in the fuel return,
   2. If air in the ruel return, locate and repair.

Test the Engine with Repair for Aerated Fuel

Perform the following steps to determine if the aerated fuel repair resolved the misfiring cylinder condition: ‪

1. Start engine.
2. Run engine at 1000 r/min.
3. Listen for misfiring cylinder.
   1. If the engine is not misfiring, no further troubleshooting is required. Shut down the engine.
   2. If the engine is misfiring, check for improper injector setting. Shut down the engine;

To determine if poor vehicle ground is causing the cylinder to misfire, perform the following steps: ‪

1. Remove alternator belt.
2. Start the engine.
3. Run the engine through operating range.
4. Listen for engine misfiring.
   1. If the engine is not misfiring. Shut down the engine.
   2. If the engine is still misfiring, check for aerated fuel;

Negative Lead Repair

Perform the following steps for negative lead repair: ‪

1. Shut down the engine.
2. Remove negative lead(s) at frame ground stud near battery box.
3. Clean ground stud; refer to OEM guidelines.
4. Clean negative lead(s) terminal lugs with low grit sandpaper.
5. Repair any loose or damaged lead(s), using the splice method or rosin core solder.
6. Install negative lead(s) to frame ground stud; refer to OEM guidelines.
7. Install alternator belt. Tighten belt to:
   1. If installing a new belt, tighten to 170 N · m (125 lb).
   2. If installing a used belt, tigthen to 135 N · m (100 lb).
   3. If a belt tension gage is not available, adjust the belt tension so that a firm push with the thumb, at a point midway between the two pulleys, will depress the belt 12.70 – 19.05 mm (0.500 -0.750 in.).Note: When installing or adjusting an accessory drive belt, be sure the bolt at the accessory adjusting pivot point is properly tightened, as well as the bolt in the adjusting slot.Note: Drive belts (Vee and poly-vee) should be replaced every 2,000 hours or 100,000 miles (160,000 km).
8. Verify negative lead repair;

Verification of Repair for Negative Lead

Perform the following steps to determine if negative lead repair resolved the misfiring cylinder condition: ‪

1. Start engine.
2. Run engine speed up to the occurrence of the misfiring.
3. Listen for misfiring cylinder.
   1. If the engine is not misfiring, no further troubleshooting is required. Shut down the engine.
   2. If the engine is misfiring, check for aerated fuel. Shut down the engine;