Service Bulletin Published by Sudden Service, Inc. Volume 18 / Number 2 / February 1, 2018 Louisville, Mississippi Preventative Maintenance (PM) Requirements for Diesel Engines Equipped With EPA Tier 4 Aftertreatment Systems CumminsQSB6.7 T4i and T4f Taylor Models T-180S through T-360M, TH-350L through TH-400L, T-450S through T520S, -180S through -360L, H-350L thorugh H--400L, -450S through -520S The above referenced Taylor models with the Cummins QSB6.7 Tier 4 (interim) and Tier 4 (final) certified engines are equipped with aftertreatment systems which include components related to exhaust gas recirculation (EGR). The EGR system reduces nitrous oxide emissions by strategically introducing and metering exhaust gases through the engine intake and into the combustion chamber. By supplementing a quantity of the intake air charge with spent exhaust gas, the formation of nitrous oxides during the combustion process can be reduced. The EGR system includes an EGR valve, among other components, where the distribution of exhaust gases is controlled. During operation, the EGR valve will accumulate deposits which must be cleaned for efficient long-term operation. In some duty cycles, the accumulation of deposits is accelerated; and in these cases, without maintenance, the accumulation can lead to poor engine performance and eventual premature component failure. Because the engine aftertreatment system involves many components and sub-systems, improper maintenance or operation of non EGR specific components can result in problems which present themselves in the EGR valve as well. Therefore, for extended, efficient operation of the Cummins engine and engine aftertreatment system, it is imperative that proper maintenance schedules be closely followed. Additionally, Taylor is introducing an important preventative maintenance (PM) item which applies specifically to inspecting and cleaning, if necessary, the EGR valve on a regular interval. The preventative maintenance (PM) schedule for the entire Taylor lift truck can be found in your truck s Maintenance Manual. For your convenience, the PM schedule for the engine and aftertreatment system is provided below including the new PM item related to EGR valve inspection and cleaning. Further, the Cummins recommended procedure for removal, inspection of the EGR valve, cleaning (if necessary) and reinstallation is also provided below. Revisions to affected Maintenance Manuals will be made as soon as possible to include the new Preventive Maintenance exhaust gas recirculation valve inspection point as well as to add the Cummins recommended procedures. Sudden Service Inc.
Preventive Maintenance Service Symbols Service Intervals A-Adjust C-Clean -Change D-Drain GR-Grease -Check 10 hrs. 500 hrs. 1000 hrs. 1500 hrs. 2000 hrs. POWER UNIT ENGINE (Refer to The Engine Manufacturer s Maintenance Manual for Additional Requirements): Oil level - check for evidence of external leakage Oil change and filter (or every 6 months) D/ Inspect vibration damper (or every 2 years) Clean engine, and check engine mounts and bolts C/ Engine crankcase filter DEF dosing unit filter DEF suction filter DEF tank (clean as conditions warrant) ADDITIONAL PM REQUIREMENT Exhaust Gas Recirculation (EGR) valve remove, inspect and clean (if necessary). FUEL SYSTEM: /C Fill fuel tank - check for leaks Fuel filter with fuel / water separator (or every 6 months) D Fuel filter (or every 6 months) Fuel tank, cap, hoses and clamps AIR INTAKE SYSTEM: Check for leaks Air cleaner filter indicator Air cleaner primary filter (or by filter indicator) * Air cleaner safety filter (as conditions warrant) * COOLING SYSTEM: Coolant level, fan belts, hoses, clamps and radiator - check for leaks Drain and flush cooling system (or every 2 years) Radiator and Charge air cooler (clean externally as conditions warrant) ELECTRICAL SYSTEM: Check all Emergency Stops to ensure proper operating function Battery - check water level C D/ Alternator belts * Checks, grease intervals, oil and filter changes are based on normal operating conditions including ten hours per day, fifty hours per week. If your operating conditions or duty cycles are more severe, service should be conducted more frequently. Extremely dusty conditions may require more frequent grease intervals and oil / filter changes.
Preparatory Steps WARNING: Batteries can emit explosive gases. To reduce the possibility of personal injury, always ventilate the compartment before servicing the batteries. To reduce the possibility of arcing, remove the negative (-) battery cable first and attach the negative (-) battery cable last. Note: Brush away all loose dirt from the around the area of the air handling connections to avoid contamination of the interior of the engine. Disconnect the battery cables. Refer to the original equipment manufacturer (OEM) service manual. Disconnect the exhaust gas recirculation (EGR) connection tube from the EGR valve. Reference the following procedure for QSB6.7 CM2350 B105 engines. Refer to Procedure 011-025 in Section 11. Reference the following procedure for QSL9 CM2350 L102 engines. Refer to Procedure 011-025 in Section 11. Disconnect the electrical connection from the EGR valve. Remove Clean the area around the EGR valve with a clean cloth to help prevent debris from entering the air intake system when the EGR valve is removed. Remove the four capscrews holding the EGR valve to the air intake connection and remove the EGR valve. Use protective caps from the Air Handling Clean Care Kit, Part Number 4919498, or equivalent, or heavy tape to cover any open connections to prevent debris from entering the system. Clean and Inspect for Reuse Clean the EGR valve and air intake connection mounting surfaces of gasket material. Take care to keep any debris out of the air intake system. Note: A light coating of carbon is common on the inside of the EGR valve, and does not need to be removed. Note: The EGR valve can have a corrosion resistant coating on the inner surfaces. Do not scratch or remove this coating.
Remove the four capscrews that hold the EGR valve motor to the EGR valve base. Remove the EGR valve motor. Take care to keep the shim with the motor. Note: Note the orientation of the electrical connector with respect to the valve body. A witness mark on the outside of the motor case and valve body can be used to document the orientation. This orientation must be the same upon assembly. Note: The shim (1) is specific to the valve and cannot be replaced. If the shim is lost or damaged, replace the EGR valve. Use two fingers to press down the valve spring retainer (1) to unlock the two valve keepers (2). If the valve keepers will not release using finger pressure, locate a 5/8 deep socket to the spring retainer (1). Gently tap on the socket with a small hammer to release the keepers, then use two fingers and press for keeper removal. Note: The spring, spring keepers, and spring retainer cannot be replaced. If the spring, spring keepers, or spring retainer are lost or damaged, replace the EGR valve. Clean the accumulated soot from the EGR valve inlet port and outlet ports with a nylon bristle and/or wire brush. Some deposits may need to be scraped out with a pick or scraping tool. Remove as much material as possible before applying any cleaner, without damaging the poppet sealing surfaces and the anti-corrosion finish, inside the EGR valve body.
Clear the area around the soot guard (1) in the outlet port with a 90-degree bent pick. Clear any deposit material all the way around the front and the back of the soot guard. Make sure that there is no deposit material on or around the soot guard that could hold the poppet shaft open. WARNING: When using solvents, acids, or alkaline materials for cleaning, follow the manufacturer s recommendations for use. Wear goggles and protective clothing to reduce the possibility of personal injury. Spray carburetor cleaner into the EGR valve outlet ports to soak the inner surfaces. Use Clean Care Kit, Part Number 4919501, available in the ISB CM2150 and CM2250 Clean Care Kit, Part Number 4919498, to seal the EGR valve inlet. Fill the EGR valve cavity with carburetor cleaner. Soak for 5 minutes. Work the poppet shaft back and forth and turn it while the poppets are in contact with the valve seats (closed position) to help clean the valve. After 5 minutes, drain and properly dispose of the excess cleaner. Note: Carburetor cleaner is the most effective solvent for this procedure. Do not substitute any other cleaning solvent. The EGR valve shaft stem (1) is comprised of two valve faces (2) on two valve seats (3). Use a small nylon or brass wire brush to lightly brush away loose soot from the stem (1), valve seat (3), and from the valve seat on the EGR valve housing. Take care not to damage the poppet sealing surfaces. Spray additional carburetor cleaner as needed to clean the sealing surfaces. Note: Carburetor cleaner is the most effective solvent for this procedure. Do not substitute any other cleaning solvent. The soot guard (1) is comprised of outer and inner cylinders which must be able to close with a small gap at the bottom. Use a small nylon or brass wire brush to brush away deposits from the soot guard. Deposits can be on the back side of the soot guard causing the valve not to close fully. Spray additional carburetor cleaner as needed to clean the sealing surfaces. Note: Carburetor cleaner is the most effective solvent for this procedure. Do not substitute any other cleaning solvent.
WARNING: Wear appropriate eye and face protection when using compressed air. Flying debris and dirt can cause personal injury Drain any remaining carburetor cleaner from the EGR valve and properly dispose of the liquid. Use compressed air to dry the inside of the EGR valve. Repeat the cleaning steps, if necessary. Note: An effectively cleaned valve will close with a metal sound when the poppet shaft is closed. A soft thud is an indication that deposits are still holding the EGR valve partially open. Install the spring, spring retainer, and spring keepers. Install the EGR valve motor, shim, and four capscrews to the base. Torque Value: EGR Motor Capscrews 2.5 n m [ 22 in-lb. ] Note: The EGR valve motor electrical connector must be oriented in the same direction as it was when originally installed. Inspect the engine wiring harness EGR valve actuator connector for corrosion, worn receptacles, or other damage. Replace the engine wiring harness EGR valve connector if corrosion, worn receptacles, or other damage is found.
After cleaning the EGR valve, connect the electrical connector to the EGR valve and turn the ignition key ON. Do not start the engine. Check for active Fault Code 1896. If Fault Code 1896 persists after cleaning, replace the EGR valve. Inspect the EGR valve seats and stem for galling, pitting, cracks, or excessive corrosion. Note: Soot and condensation leaking from the weep hole on the EGR valve is considered normal and does not mean that the EGR valve needs to be replaced. If the EGR valve shows signs of internal damage, replace the EGR valve assembly. Install Install the EGR valve, with new mounting gaskets, onto the air intake connection. Install the four capscrews holding the EGR valve to the air intake connection hand tight to minimize assembly stresses on the EGR connection tube. Tighten in a crisscross pattern. Torque Value: 24 n m [ 212 in-lb. ] Finishing Steps WARNING: Batteries can emit explosive gases. To reduce the possibility of personal injury, always ventilate the compartment before servicing the batteries. To reduce the possibility of arcing, remove the negative (-) battery cable first and attach the negative (-) battery cable last. Connect the EGR connection tube to the EGR valve. Reference the following procedure for QSB6.7 CM2350 B105 engines. Refer to Procedure 011-025 in Section 11. Reference the following procedure for QSL9 CM2350 L102 engines. Refer to Procedure 011-025 in Section 11. Connect the engine harness to the EGR valve. If a malfunction resulted in coolant, oil, excessive fuel or excessive black smoke entering the exhaust system, the aftertreatment system must be inspected. Refer to Procedure 014-015 in section 14. Connect the battery cables. Refer to the OEM service manual. Operate the engine and check for leaks.