Page 1 of 31 (/qs3/pubsys2/xml/en/manual/2883567/2883567-titlepage.html) Select Service Tools Recommended Cummins Service Tools 0.043 inch orificed diagnostic fuel line, Part Number 3164621 Diagnostic fuel line, Part Number 4918695 Diagnostic fuel line, Part Number 4918696 Multimeter pressure/vacuum transducer adapter, Part Number 3164491 M10 male Compuchek fitting, Part Number 3824842 Fuel Pressure Gauge Adapter Kit, Part Number 4918324 Fuel drain hose, Part Number 4918295, 4918434, 4918698, or 4918895 Graduated beaker, Part Number 4919139 Fuel drain hose, Part Number 3164618 Fuel System Leak Tester Kit, Part Number 4918295 Cap, Part Number 4918297 Fuel drain flow hose, Part Number 4918679 Fuel drain flow hose, Part Number 4918295 Adapter fitting, Part Number 3932302 1/8-NPT male Compuchek fitting, Part Number 3377244 Injector leakage isolation tool, Part Number 4918298. Additional Service Items 0 to 762 mm-hg [0 to 30 in-hg] vacuum gauge 0 to 1034 kpa [0 to 150 psi] pressure gauge 3 inch long or appropriate length for application, 1/8 inch NTP pipe 1/8 inch NPT T-fitting
Page 2 of 31 General Information CAUTION Clean all fittings before disassembly. Dirt or contaminants can damage the fuel system. The following procedure contains measurement steps and specifications regarding the engine s fuel system components. This procedure is not intended to take the place of troubleshooting tree repair direction. Refer to the appropriate troubleshooting tree for repair direction. Some vehicles are equipped with an engine starting motor protection feature. If the starting motor is engaged for 30 or more seconds, without the engine starting, the starting motor will be locked out from operating, allowing for proper cooling of the starting motor. During this time the Wait to Start lamp, if equipped, will flash for 2 minutes. Once the lamp discontinues flashing, the starting motor will be allowed to function. While collecting data during cranking tests, do not crank the engine for 30 seconds continuously. Crank the engine in 15 second intervals with a 15 second break between cranking. This reduces the possibility of overheating the starter motor or triggering the starter protection feature. In order to reach engine high idle, it could be necessary to temporarily adjust the Maximum engine speed without vehicle speed source parameter with INSITE electronic service tool to the high idle speed of the engine (2300 rpm for example). The procedures listed below are important fuel system checks to perform when troubleshooting fuel system related issues. Use the corresponding procedures for additional Fuel System diagnostic checks: Air in Fuel: Refer to Procedure 006-003 in Section 6 (/qs3/pubsys2/xml/en/procedures/155/155-006-003-tr-isb13.html) Fuel Inlet Restriction: Refer to Procedure 006-020 in Section 6 (/qs3/pubsys2/xml/en/procedures/155/155-006-020-tr-isb13.html) Fuel Drain Line Restriction: Refer to Procedure 006-012 in Section 6 (/qs3/pubsys2/xml/en/procedures/155/155-006-012-tr-isb13.html) Fuel System Priming: Refer to Procedure 006-015 in Section 6 (/qs3/pubsys2/xml/en/procedures/155/155-006-015-tr-isb13.html) Fuel System Specifications: Refer to Procedure 018-016 in Section V. (/qs3/pubsys2/xml/en/procedures/155/155-018-016-tr-isb13.html)
Page 3 of 31 Preparatory Steps WARNING Wear appropriate eye and face protection when using compressed air. Flying debris and dirt can cause personal injury. WARNING When using a steam cleaner, wear safety glasses or a face shield, as well as protective clothing. Hot steam can cause serious personal injury. WARNING The fuel pump, high-pressure fuel lines, and fuel rail contain very high-pressure fuel. Do not loosen any fittings while the engine is running. Wait at least 10 minutes after shutting down the engine before loosening any fittings in the highpressure fuel system to allow pressure to decrease to a lower level. WARNING Depending on the circumstance, diesel fuel is flammable. When inspecting or performing service or repairs on the fuel system, to reduce the possibility of fire and resulting severe personal injury, death, or property damage, never smoke or allow sparks or flames (such as pilot lights, electrical switches, or welding equipment) in the work area. WARNING Do not bleed the fuel system of a hot engine; this can result in fuel spilling onto a hot exhaust manifold, which can cause a fire.
Page 4 of 31 Before diagnosing any fuel system component, (such as fuel lines, fuel pump, injectors, fuel rail, etc.) which would expose the fuel system or internal engine component to potential contaminants, prior to disassembly, clean the fittings, mounting hardware, and the area around the component to be removed. Dirt or contaminants can be introduced into the fuel system and engine if the surrounding areas are not cleaned, resulting in damage to the fuel system and engine. Refer to Procedure 000-009 in Section 0 (/qs3/pubsys2/xml/en/procedures/99/99-000- 009.html) for cleaning information. Low-Pressure System Check CAUTION Clean all fittings before disassembly. Dirt or contaminants can damage the fuel system. The low-pressure system check is designed to help troubleshoot the low pressure side fuel system by taking multiple fuel system checks at one time while the engine is running or cranking. Note : The tool set up for the low pressure system check may be slightly different than the setup described in the Air in Fuel, Fuel Inlet Restriction, and Fuel Drain Line Restriction procedures. The reason is that the procedures are written to be performed individually and not all at once. The difference between those procedures and the low pressure system setup is the use and location of the 0.043-inch orificed diagnostic fuel line, Part Number 3164621. Based on the additional clear lines installed during the low pressure system check setup, the 0.043-inch orificed diagnostic fuel line, Part Number 3164621, can be installed at the fuel filter outlet diagnostic port. Using the 0.043-inch orificed diagnostic fuel line does not have a significant effect on the drain line restriction measurement, but it is necessary to use when performing the fuel filter restriction measurement. Initial Setup Air in Fuel and Fuel Inlet Restriction Setup
Page 5 of 31 1. Install the diagnostic fuel line, Part Number 4918696, between the pressure side fuel filter fuel supply inlet fitting and the fuel line connector. This line will be used to check for air in the fuel before the pressure side filter. 2. Install the diagnostic fuel line, Part Number 4918696, or sight glass at the suction side fuel filter inlet connection. This is used to check for air in the fuel. 3. Install diagnostic fuel line, Part Number 4918895 or 4918696, between the gear pump original equipment manufacturer (OEM) fuel supply line and the gear pump inlet fitting. This line will be used to check for fuel inlet restriction at the fuel gear pump and for air in the fuel. Note : If the fuel gear pump inlet connection does not use quick connect fittings, use the following procedures for the setup instructions. Refer to Procedure 006-003 in Section 6. (/qs3/pubsys2/xml/en/procedures/155/155-006-003-tr-isb13.html) Refer to Procedure 006-020 in Section 6. (/qs3/pubsys2/xml/en/procedures/155/155-006-020-tr-isb13.html) A sight glass and test line will need to be installed. 4. Attach a 0 to 762 mm-hg [0 to 30 in-hg] vacuum gauge or multimeter pressure transducer, Part Number 3164491, to the diagnostic fuel line. Verify the test lines are not kinked or leaking after installation. Fuel Filter Restriction Setup
Page 6 of 31 Note : The fuel inlet and outlet are labeled on the fuel filter head using text or arrows. The illustrations do not necessarily display the true orientation of the inlet or outlet of the fuel filter. 1. Install a M10 male Compuchek fitting, Part Number 3824842, into the diagnostic port on the inlet side of the fuel filter. Note : The fuel filter head mounting capscrews may need to be loosened in order to center the test ports for attaching to the Compuchek fitting. If there is not enough clearance to install the Compuchek fitting, Part Number 3824842, an adapter fitting, Part Number 3932302, and an 1/8-NPT male Compuchek fitting, Part Number 3377244 or 3042618, can be used to aid accessibility. 2. Connect a 0 to 1034 kpa [0 to 150 psi] fuel pressure gauge or multimeter pressure transducer, Part Number 3164491, to the Compuchek fitting. Construct a T-adapter fitting using one adapter fitting, Part Number 3932302, a 3 inch long 1/8 inch NTP pipe (or appropriate length for application), an 1/8 inch NPT "T" fitting, and two 1/8-inch NPT Compuchek fittings, Part Number 3377244 or 3042618. Note : Do not use a female Compuchek fitting when constructing the T-adapter. If a female Compuchek fitting is used, the pressure readings will be inaccurate. 3. Install the T-adapter fitting into the diagnostic port on the outlet side of the fuel filter. 4. Connect a 0.043-inch orificed diagnostic fuel line, Part Number 3164621, to the T-adapter Compuchek fitting. Run the fuel hose back to the fuel tank or into a bucket. The diagnostic line is used to simulate running the engine at rated fuel system flow rate.
Page 7 of 31 Note : If engine will not start, do not install the 0.043-inch orificed diagnostic fuel line, Part Number 3164621, at the outlet of the fuel filter head. 5. Connect a 0 to 1034 kpa [0 to 150 psi] pressure gauge or multimeter pressure transducer, Part Number 3164491, to the "T" adapter Compuchek fitting. Regardless of what type of pressure measurement tool is used (gauge or multimeter pressure transducer), make sure it is calibrated and functioning properly prior to use. Make certain the test lines are not kinked or leaking after installation. Drain Line Restriction Setup Remove the OEM fuel drain line from the high pressure injection pump drain connection. Install the Fuel Pressure Gauge Adapter Kit, Part Number 4918324, into the drain connection. Make certain the test lines are not kinked or leaking after installation. Summary of Tools Installed: 1. Diagnostic fuel line between the pressure side fuel filter inlet fitting and the fuel line connector: This line is used to check for air in the fuel before the pressure side filter. 2. Diagnostic fuel line or sight glass before OEM suction side fuel filter: This line is used to check for air in the fuel. The illustration shows an enginemounted suction side fuel filter, but OEMs can choose to remote mount the fuel filter on the chassis. 3. Pressure-side fuel filter inlet pressure gauge. 4. Pressure-side fuel filter outlet pressure gauge.
Page 8 of 31 5. 0.043-inch orificed diagnostic fuel line, Part Number 3164621, attached to the T-adapter Compuchek fitting at the fuel filter outlet. Run the fuel hose back to the fuel tank or into a bucket. The diagnostic line is used to simulate running the engine at rated fuel system flow rate as needed for test purposes. The diagnostic line is not used when the engine will not start. 6. Diagnostic fuel line between the fuel gear pump OEM fuel supply line and the fuel gear pump inlet fitting. This line is used to check for fuel inlet restriction at the fuel gear pump and for air in the fuel. If the fuel gear pump does not use quick connect fittings then a sight glass and pressure gauge adapter kit will need to be used. 7. Fuel pressure gauge adapter kit at the fuel pump outlet drain connection: This line is used to check the fuel drain line restriction. Use the manual priming pump to prime the fuel system and to help remove air from the fuel system introduced while installing the test lines. Use the following procedure for fuel system priming information. Refer to Procedure 006-015 in Section 6. (/qs3/pubsys2/xml/en/procedures/155/155-006-015-trisb13.html) Note : During fuel system priming, it may be necessary to remove the 0.043-inch orificed diagnostic fuel line, Part Number 3164621, at the T-adapter Compuchek fitting to speed up fuel system priming. If the engine will not start, perform low pressure system checks at engine cranking. Prior to performing the low pressure system checks, crank the engine for 30 seconds to help purge air from the fuel system due to the newly installed diagnostic fuel lines.
Page 9 of 31 If the engine will start, allow the engine to operate at high idle for 1 minute, or until the air is purged from the newly installed diagnostic fuel lines, then perform the low pressure system checks. Measurement - Engine Will Start This part of the procedure is for measuring the lowpressure system for an engine that will start. Check for air in the fuel with engine running at high idle (2300 rpm). Check for air in the fuel in the diagnostic fuel line or sight glass at the suction side fuel filter inlet connection. Check for air in the fuel in the diagnostic fuel line between the gear pump OEM fuel supply line and the fuel gear pump inlet. Check for air in the fuel in the diagnostic fuel line between the pressure side fuel filter fuel supply inlet fitting and the fuel line connector. Check for air in the fuel out of the 0.043-inch orificed diagnostic fuel line, Part Number 3164621, (installed at the outlet of the fuel filter head). There should not be any air present. Refer to the appropriate troubleshooting tree for repair direction. Measure inlet restriction with the engine running at high idle. Make sure a 0.043-inch orificed diagnostic fuel line, Part Number 3164621, is installed at the outlet of the fuel filter head. Fuel Inlet Restriction at High Idle (2300 rpm) mm-hg in-hg 305 MAX 12
Page 10 of 31 Refer to the appropriate troubleshooting tree for repair direction. Measure drain line restriction with the engine running at high idle. Make sure a 0.043-inch orificed diagnostic fuel line, Part Number 3164621, is installed at the outlet of the fuel filter head. Drain Line Restriction at High Idle (2300 rpm) kpa psi 18.6 MAX 2.7 Refer to the appropriate troubleshooting tree for repair direction. Measure the gear pump pressure at the fuel filter inlet with the engine running at high idle. Make sure a 0.043-inch orificed diagnostic fuel line, Part Number 3164621, is installed at the outlet of the fuel filter head. Gear Pump Pressure at High Idle (2300 rpm) kpa psi 207 MIN 30 650 MAX 94.3 Refer to the appropriate troubleshooting tree for repair direction. Measure the fuel filter restriction with the engine running at high idle. Make sure a 0.043-inch orificed diagnostic fuel line, Part Number 3164621, is installed at the outlet of the fuel filter head.
Page 11 of 31 Record the fuel pressure at the inlet and outlet of the fuel filter. Subtract the outlet reading from the inlet reading to determine the fuel filter restriction. Pressure Drop Across Fuel Filter at High Idle (2300 rpm) kpa psi 81 MAX 11.7 Refer to the appropriate troubleshooting tree for repair direction. Measurement - Engine Will Not Start This part of the procedure is for measuring the lowpressure system for an engine that will not start. Note : If the engine will not start, do not install 0.043-inch orificed diagnostic fuel line, Part Number 3164621, at the outlet of the fuel filter head. Do not crank the engine for 30 seconds continuously. Crank the engine in 15 second intervals with a 15 second break between cranking. This reduces the possibility of overheating the starter motor or triggering the starter protection feature. Check for air in the fuel with the engine cranking. Check for air in the fuel in the diagnostic fuel line or sight glass at the suction-side fuel filter inlet connection. Check for air in the fuel in the diagnostic fuel line between the gear pump OEM fuel supply line and the fuel gear pump inlet. Check for air in the fuel in the diagnostic fuel line between the pressure side fuel filter fuel supply inlet fitting and the fuel line connector. There should not be any air present.
Page 12 of 31 Refer to the appropriate troubleshooting tree for repair direction. Measure drain line restriction with the engine cranking. Note : If the engine will not start, do not install 0.043-inch orificed diagnostic fuel line, Part Number 3164621, at the outlet of the fuel filter head. Do not crank the engine for 30 seconds continuously. Crank the engine in 15 second intervals with a 15 second break between cranking. This reduces the possibility of overheating the starter motor or triggering the starter protection feature. Drain Line Restriction at Engine Cranking (150 rpm minimum) kpa psi 18.6 MAX 2.7 Refer to the appropriate troubleshooting tree for repair direction. Measure the gear pump pressure at the fuel filter inlet with the engine cranking. Note : If the engine will not start, do not install 0.043-inch orificed diagnostic fuel line, Part Number 3164621, at the outlet of the fuel filter head. Do not crank the engine for 30 seconds continuously. Crank the engine in 15 second intervals with a 15 second break between cranking. This reduces the possibility of overheating the starter motor or triggering the starter protection feature. Gear Pump Pressure at Engine Cranking (150 rpm minimum) kpa psi
Page 13 of 31 Gear Pump Pressure at Engine Cranking (150 rpm minimum) kpa psi 207 MIN 30 500 MAX 72.5 Refer to the appropriate troubleshooting tree for repair direction. Measure the fuel filter restriction with the engine cranking. Note : If the engine will not start, do not install 0.043-inch orificed diagnostic fuel line, Part Number 3164621, at the outlet of the fuel filter head. Do not crank the engine for 30 seconds continuously. Crank the engine in 15 second intervals with a 15 second break between cranking. This reduces the possibility of overheating the starter motor or triggering the starter protection feature. Record the fuel pressure at the inlet and outlet of the fuel filter. Subtract the outlet reading from the inlet reading to determine the fuel filter restriction. Pressure Drop Across Fuel Filter at Engine Cranking (150 rpm minimum) kpa psi 81 MAX 11.7 Refer to the appropriate troubleshooting tree for repair direction.
Page 14 of 31 Fuel Lift Pump Flow Test CAUTION Clean all fittings before disassembly. Dirt or contaminants can damage the fuel system. The fuel lift pump or priming pump can be a Cummins or OEM supplied component. If a Cummins supplied priming pump is not installed or is of a different design, refer to the OEM service manual for fuel system priming pump flow testing. The purpose of this test is to check lift pump flow. Disconnect the fuel supply line from the fuel priming pump fuel filter head outlet. Attach the fuel drain hose, Part Number 4918296 (part of kit, Part Number 4918295), to the priming pump fuel filter head outlet fitting. The other end of the hose will be placed in a graduated beaker, Part Number 4919139. Additional fuel drain hose(s), Part Number 4918295, 4918434, 4918698 or 4918895, can be used to substitute Part Number 4918296. Note : Make certain the fuel lines are not kinked or leaking after installing the test lines. Note : This test is performed with the engine not running. Make certain all air is purged from the test lines and fuel is flowing consistently before collecting data. Verify that no leakage is present at the shaft while pumping the priming knob. Unlock the priming pump knob (1) and pull it out. Pump the priming knob a few times to push air out of the line. Once fuel is flowing from the line consistently, place the end of the hose in a graduated beaker, Part Number 4919139, and pump the priming pump ten times. One pumping stroke is equal to the knob being pulled
Page 15 of 31 out and pushed back in. The fuel flow rate for the priming pump must be greater than 137 ml [4.6 fl-oz] after ten pumps of the priming knob. Note : For an accurate measurement, it is a good idea to collect three different flows and average the results. If no resistance is felt while pumping the knob, the priming pump check valve may be damaged or stuck open with debris. For repair related information, refer to the OEM service manual. If the priming pump does not meet the flow specifications, but resistance is felt when pumping the priming knob: Check for air in the fuel. Refer to Procedure 006-003 in Section 6. (/qs3/pubsys2/xml/en/procedures/155/155-006-003- tr-isb13.html) Check the fuel inlet restriction. Refer to Procedure 006-020 in Section 6. (/qs3/pubsys2/xml/en/procedures/155/155-006-020- tr-isb13.html) If no problems are found, the priming pump is malfunctioning. Replace the priming pump. For repairrelated information, refer to the OEM service manual. High-Pressure Fuel Pump Supply Flow Test Initial Setup WARNING The fuel pump, high-pressure fuel lines, and fuel rail contain very high pressure fuel. Do not loosen any fittings while the engine is running. Wait at least 10
Page 16 of 31 minutes after shutting down the engine before loosening any fittings in the high pressure fuel system to allow pressure to decrease to a lower level. CAUTION Clean all fittings before disassembly. Dirt or contaminants can damage the fuel system. Disconnect the high-pressure fuel outlet line from the high-pressure injection pump. Refer to Procedure 006-071 in Section 6. (/qs3/pubsys2/xml/en/procedures/155/155-006-071-trisb13.html) Insert a piece of tubing over the outlet fitting of the fuel pump and route it into a 500 ml graduated beaker, Part Number 4919139. Make certain the test lines are not kinked or leaking after installation. Measurement Crank the engine and measure the amount of fuel exiting the fuel pump. Prior to collecting data, crank the engine for 30 seconds to help purge air from the newly installed diagnostic fuel line. Do not crank the engine for 30 seconds continuously. Crank the engine in 15 second intervals with a 15 second break between cranking. This reduces the possibility of overheating the starter motor or triggering the starter protection feature.
Page 17 of 31 Minimum High Pressure Fuel Pump Supply Flow with Engine Cranking (150 rpm minimum) in 30 Seconds ml fl-oz 70 MIN 2.4 Note : For an accurate measurement, it is a good idea to collect three different flows and average the results. Use the following procedure to connect the highpressure fuel outlet line to the high-pressure injection pump. Refer to Procedure 006-071 in Section 6. (/qs3/pubsys2/xml/en/procedures/155/155-006-071-trisb13.html) Refer to the appropriate troubleshooting tree for repair direction. Fuel Pump Gear Pump Pressure Test CAUTION Clean all fittings before disassembly. Dirt or contaminants can damage the fuel system. If the engine can be started, measurement of the fuel pressure out of the fuel gear pump can diagnose a fuel system or fuel pump problem. Refer to the Fuel Filter Restriction section in this procedure for the setup and measurement of the fuel gear pump pressure into the fuel filter. Refer to the appropriate troubleshooting tree for repair direction.
Page 18 of 31 Fuel Filter Restriction Test CAUTION Clean all fittings before disassembly. Dirt or contaminants can damage the fuel system. Use the following procedure to check the suction side filter restriction. Refer to Procedure 006-020 in section 6. (/qs3/pubsys2/xml/en/procedures/155/155-006-020-trisb13.html) Check the pressure side fuel filter restriction by measuring the pressure drop across the fuel filter using the following steps. If the engine will start, make certain that the engine is at operating temperature (88 C [190 F] or open thermostat) before connecting the lines and running the test. The fuel pressure filter restriction should be measured at rated engine fuel system flow. The 0.043-inch orificed diagnostic fuel line, Part Number 3164621, at the outlet of the fuel filter head, is used to simulate running the engine at rated fuel system flow. Initial Setup The fuel inlet and outlet are labeled on the fuel filter head using text or arrows. The illustrations do not necessarily display the true orientation of the inlet or outlet of the fuel filter. 1. Install an M10 male Compuchek fitting, Part Number 3824842, into the diagnostic port on the inlet side of the fuel filter.
Page 19 of 31 Note : The fuel filter head mounting capscrews may need to be loosened in order to center the test ports for attaching to the Compuchek fitting. If there is not enough clearance to install the Compuchek fitting, Part Number 3824842, an adapter fitting, Part Number 3932302, and an 1/8-NPT male Compuchek fitting, Part Number 3377244 or 3042618, may be used to aid accessibility. 2. Connect a 0 to 1034 kpa [0 to 150 psi] fuel pressure gauge or multimeter pressure transducer, Part Number 3164491, to the Compuchek fitting. Construct a T-adapter fitting using one adapter fitting, Part Number 3932302, a 3 inch long 1/8 inch NTP pipe (or appropriate length for application), an 1/8 inch NPT T-fitting, and two 1/8-inch NPT Compuchek fittings, Part Number 3377244 or 3042618. Note : Do not use a female Compuchek fitting when constructing the T-adapter. If a female Compuchek fitting is used, the pressure readings will be inaccurate. 3. Install the T-adapter fitting into the diagnostic port on the outlet side of the fuel filter. 4. Connect a 0.043-inch orificed diagnostic fuel line, Part Number 3164621, to the T- adapter Compuchek fitting. Run the fuel hose back to the fuel tank or into a bucket. The diagnostic line is used to simulate running the engine at rated fuel system flow rate. 5. Connect a 0 to 1034 kpa [0 to 150 psi] pressure gauge or multimeter pressure transducer, Part Number 3164491, to the T-adapter Compuchek fitting. Regardless of what type of pressure measurement tool is used (gauge or multimeter pressure transducer), make sure it is calibrated and functioning properly prior to use.
Page 20 of 31 Make certain the test lines are not kinked or leaking after installation. Measurement - Engine Will Not Start If the engine will not start, measure the fuel pressure while cranking the engine. Note : If engine will not start, do not install 0.043- inch orificed diagnostic fuel line, Part Number 3164621, at the outlet of the fuel filter head. Prior to collecting data, crank the engine for 30 seconds to help purge air from the newly installed diagnostic fuel line. Do not crank the engine for 30 seconds continuously. Crank the engine in 15 second intervals with a 15 second break between cranking. This reduces the possibility of overheating the starter motor or triggering the starter protection feature. Fuel Pressure Range at Fuel Filter with Engine Cranking (150 rpm minimum) kpa psi 207 MIN 30 500 MAX 72.5 Record the fuel filter outlet pressure value and subtract it from the fuel filter inlet pressure. Maximum Allowable Pressure Drop Across Fuel Filter while Cranking (150 rpm minimum) kpa psi 81 MAX 11.7 Refer to the appropriate troubleshooting tree for repair direction. Measurement - Engine Will Start
Page 21 of 31 If the engine will start, make certain that the engine is at operating temperature (88 C [190 F] or open thermostat) before connecting the lines and running the test. Note : Make certain a 0.043 inch orificed diagnostic fuel line, Part Number 3164621, is installed at the outlet of the fuel filter head. Prior to collecting data, operate the engine for 1 minute to help purge air from the newly installed diagnostic fuel line. Measure the fuel pressure at high idle. Fuel Pressure Range at Fuel Filter with Engine at High Idle (2300 rpm) kpa psi 207 MIN 30 650 MAX 94.3 Record the fuel filter outlet pressure value and subtract it from the fuel filter inlet pressure. Maximum Allowable Pressure Drop Across Fuel Filter while Engine Running at High Idle (2300 rpm) kpa psi 81 MAX 11.7 Refer to the appropriate troubleshooting tree for repair direction. Cutout Test Perform a manual cutout test that will not start.
Page 22 of 31 With the engine not operating, disconnect the fuel line routed from the fuel rail to cylinder number 1. Refer to Procedure 006-051 in Section 6 (/qs3/pubsys2/xml/en/procedures/155/155-006-051- tr-isb13.html). Install the injector leakage isolation tool. Torque Value: 40 n m [ 30 ft-lb ] Attempt to start the engine or operate the engine at idle. Repeat the above test, as necessary, with each cylinder blocked off. High-Pressure Fuel Rail Return Flow Test CAUTION Clean all fittings before disassembly. Dirt or contaminants can damage the fuel system. The purpose of this test is to check for a fuel rail pressure relief valve (1) that leaks excessive fuel to the fuel drain (2) line. If the engine will start, make certain that the engine is at operating temperature (88 C [190 F] or open thermostat) before connecting the lines and running the test. Initial Setup Disconnect the quick connect (1) located in the drain line. Install the quick disconnect line, Part Number 4918434, onto the quick connect fitting line (2).
Page 23 of 31 Route the fuel rail drain hose, Part Number 4918434, female connector, into a graduated beaker, Part Number 4919139. Insert fuel block-off tool, Part Number 4918464, into the quick connect fitting line (3). Make certain the test lines are not kinked or leaking after installation. Measurement - Engine Will Not Start If the engine will not start, measure the fuel return flow while cranking the engine. Prior to collecting data, crank the engine for 30 seconds to help purge air from the newly installed diagnostic fuel line. Do not crank the engine for 30 seconds continuously. Crank the engine in 15 second intervals with a 15 second break between cranking. This reduces the possibility of overheating the starter motor or triggering the starter protection feature. High Pressure Fuel Rail Return Flow at Engine Cranking (150 rpm minimum) in 30 Seconds Maximum of 5 Drops Note : For an accurate measurement, it is a good idea to collect three different flows and average the results. Refer to the appropriate troubleshooting tree for repair direction. Perform a manual cutout test on engines that will not start. With the engine not operating disconnect the fuel line routed from the fuel rail to cylinder number 1. Refer to Procedure 006-051 in Section 6.
Page 24 of 31 (/qs3/pubsys2/xml/en/procedures/155/155-006-051- tr-isb13.html) Install the injector leakage isolation tool. Torque Value: 40 n m [ 30 ft-lb ] Attempt to start the engine or operate the engine at idle. Repeat the above test, as necessary, with each cylinder blocked off. Measurement - Engine Will Start If the engine will start, make certain that the engine is at operating temperature (88 C [190 F] or open thermostat) before connecting the lines and running the test. Prior to collecting data, let the engine run for 1 minute to help purge air from the newly installed diagnostic fuel line. The Fuel System Leakage Test in INSITE electronic service tool must be used to increase system pressure and therefore increase the ability to detect high leakage. Start the engine. Use INSITE electronic service tool Fuel System Leakage Test located under ECM Diagnostic Tests to start the fuel pressure override test. Measure the return fuel flow. High Pressure Fuel Rail Return Flow at Standard Idle Conditions using INSITE electronic service tool Fuel System Leakage Test in 30 Seconds ml fl-oz 8 MAX 0.27 Note : 8 ml [0.27 fl-oz] in 30 seconds equals approximately 1 drop per second.
Page 25 of 31 Note : For an accurate measurement, it is a good idea to collect three different flows and average the results. Refer to the appropriate troubleshooting tree for repair direction. High-Pressure Fuel Injector Return Flow Test CAUTION Clean all fittings before disassembly. Dirt or contaminants can damage the fuel system. The purpose of this test is to check for excessive fuel return (leakage) from the injectors/high pressure connector to the fuel drain line. The steps below will describe the set up to separate the rail, injector, and gear pump return flows at the same time. The fuel system return flows must be separated from each other to collect proper data. If the engine will start, make certain that the engine is at operating temperature (88 C [190 F] or open thermostat) before connecting the lines and running the test. Initial Setup Fuel Rail Pressure Relief Valve Return Flow: Disconnect the quick connect (1) located in the drain line. Install the quick disconnect line, Part Number 4918434, onto the quick connect fitting line (2). Route the fuel rail drain hose, Part Number 4918434, female connector, into a graduated beaker, Part Number 4919139. Insert fuel block-off tool, Part Number 4918464, into the quick connect fitting line (3).
Page 26 of 31 Make certain the test lines are not kinked or leaking after installation. Fuel Pump Return Flow: Disconnect the OEM fuel drain line from the gear pump drain connection. Remove the flow-through banjo bolt from the drain connection eyelet. Install the fuel drain flow hose, Part Number 4918679 (1) or 4918295 (2), into the fuel pump threaded drain connection. Route the fuel drain hose into a suitable container. The fuel pump return flow measurement is no longer used in troubleshooting. Never replace fuel pumps using return flow measurement. Injector Return Flow: Install fuel drain hose, Part Number 3164618, into the eyelet and cap it off with Part Number 4918297 (Part of kit Part Number 4918295). Route the fuel rail drain hose into a graduated beaker, Part Number 4919139. Measurement - Engine Will Not Start Make certain the test lines are not kinked or leaking after installation. If the engine will not start, crank the engine and measure the amount of fuel returned by the injectors. Prior to collecting data, crank the engine for 30 seconds to help purge air from the newly installed diagnostic fuel line.
Page 27 of 31 Do not crank the engine for 30 seconds continuously. Crank the engine in 15 second intervals with a 15 second break between cranking. This reduces the possibility of overheating the starter motor or triggering the starter protection feature. Injector Return Flow at Engine Cranking (150 rpm minimum) for 30 Seconds ml fl-oz 45 MAX 1.5 Note : For an accurate measurement, it is a good idea to collect three different flows and average the results. If the fuel return flow is greater than specification, it will be necessary to perform the Injector Isolation Test to block off the fuel to one injector at a time to determine the location of the leak. See the following instructions for isolating an injector. Measurement - Engine Will Start If the engine will start, make certain that the engine is at operating temperature (88 C [190 F] or open thermostat) before connecting the lines and running the test. Prior to collecting data, crank the engine for 1 minute to help purge air from the newly installed diagnostic fuel line. The Fuel System Leakage Test in INSITE electronic service tool must be used to increase system pressure and therefore increase the ability to detect high leakage. Start the engine, use the INSITE electronic service tool Fuel System Leakage Test located under ECM Diagnostic Tests to start the fuel pressure override test.
Page 28 of 31 A leak may not be detected at standard idle conditions without using INSITE electronic service tool Fuel System Leakage Test. With the fuel drain hose in a graduated cylinder, measure the injector drain flow for 30 seconds. Injector Return Flow at Standard Engine Idle Conditions using INSITE electronic service tool Fuel System Leakage Test in 30 Seconds ml fl-oz 150 MAX 5 Note : For an accurate measurement, it is a good idea to collect three different flows and average the results. If the fuel return flow is greater than specification, it will be necessary to perform the Injector Isolation Test described below to block off the fuel to one injector at a time to determine the location of the leak. Initial Setup - Injector Isolation Before attempting to isolate the leak, make sure all the high pressure fuel connectors are tightened to the correct torque. Refer to Procedure 006-052 in Section 6. (/qs3/pubsys2/xml/en/procedures/155/155-006-052-trisb13.html) If a connector is not tightened to the proper torque, tighten the connector and perform the previous test again. If the injector return flow is greater than the specified flow rate, it will be necessary to block off the fuel to one injector at a time to determine the location of the leak. WARNING
Page 29 of 31 The fuel pump, high-pressure fuel lines, and fuel rail contain very high pressure fuel. Do not loosen any fittings while the engine is running. Wait at least 10 minutes after shutting down the engine before loosening any fittings in the high pressure fuel system to allow pressure to decrease to a lower level. With the engine not running, remove the fuel injector supply line connecting the fuel rail to cylinder number 1. Refer to Procedure 006-051 in Section 6. (/qs3/pubsys2/xml/en/procedures/155/155-006-051-trisb13.html) Install the injector leakage isolation tool, Part Number 4918298, on the fuel rail where the number 1 cylinder fuel line connects. Torque Value: 40 n m [ 30 ft-lb ] Measurement - Injector Isolation Repeat the return flow test with cylinder 1 blocked off and record the flow rate. Install the fuel injector supply line. Refer to Procedure 006-051 in Section 6. (/qs3/pubsys2/xml/en/procedures/155/155-006-051-trisb13.html) Repeat the return flow test with each cylinder blocked off. Record the flow rate for each test. The flow rate will decrease below the maximum specified flow when the cylinder with the leak is blocked. The following table illustrates an example of a return flow test where a leak is present in cylinder number 5. Example Return Flow Test Results
Page 30 of 31 Cylin der Bloc ked ml/3 0 Seco nds floz/3 0 Seco nds 1 2 3 4 5 6 210 210 210 210 91 210 7 7 7 7 3 7 Note : For an accurate measurement, it is a good idea to collect three different flows and average the results. If the measurement does not meet the specifications listed, refer to the appropriate troubleshooting tree for repair direction. If this test is performed and there is not a significant change in fuel return flow while blocking off one injector, there may be a problem with more than one injector. Compare the fuel return flow difference across all injectors. (If there is more than one injector that caused a noticeable decrease in flow, they could be the leaking injectors). Another cause of this problem could be the customer is operating on fuels lighter than specified. Fuels with low viscosity will result in higher injector leakage and greater return flow rates. Use the following procedures for assembly information. Fuel Pump: Refer to Procedure 005-016 in Section 5. (/qs3/pubsys2/xml/en/procedures/155/155-005- 016-tr-isb13.html) Injector Supply Lines (High-Pressure): Refer to Procedure 006-051 in Section 6.
Page 31 of 31 (/qs3/pubsys2/xml/en/procedures/155/155-006-051- tr-isb13.html) Fuel Connector (Head Mounted): Refer to Procedure 006-052 in Section 6. (/qs3/pubsys2/xml/en/procedures/155/155-006-052- tr-isb13.html) Finishing Steps Remove all test equipment. Operate the engine and check for leaks. Last Modified: 14-Nov-2017