Lube Oil System PDF

G C G E 6, G G G c; c( G c c G c LJ G Lube Oil System G c c 8il Introduction d, The complete engine lubricating oil system is a combination of three separate systems. These are the main l...

G C G E 6, G G G c; c( G c c G c LJ G Lube Oil System G c c 8il Introduction d, The complete engine lubricating oil system is a combination of three separate systems. These are the main lubricating system, the piston cooling system and the G scavenging oil system. Turbocharged engines use a fourth system, the soak back or turbo lube system. Another oil system that is available as an option or as an upgrade is the self Ci contained pre-lube system. C Each system has its own oil pump. The main lube oil pump and piston cooling oil c pump, although individual pumps, are both contained in one housing and driven from a common drive shaft. The scavenging oil pump is a separate pump, as is the turbo c lube pump. c1 The main lube, piston cooling, and scavenging oil pumps are driven from the G accessory gear train at the front of the engine. Parts of the complete oil system and a schematic arrangement of oil circulation are shown in Figures 6.1A for a turbocharged GI engine, and 6.1b for a blower type engine on the following two pages. G G c L c c IlS Locomotive Training Series - Student Text 6-1 I G.L  n@n 7. Oil P m u u n Line To Govemor 8. Cun.h.tt Oil P u u g e (lo Camehaft Baring. M d Cylinder Rocker Anna) 9. Soak Back Filter 10. Turbocharger FilW 11. Turbochugr Filter Oil Supply M ~ l t o l d 12. Oil Line To Right and Left Bank CMUMI Ddve and To Turbo Filter 2. Oil Sttainer Housing 13. Oil Linm To Camshaft Stubshaft8 3. Main Lube Oil and Piston Cooling Oil Purnr, 14. Oil Line to No. 2 Idler Qu- Stubshaft - ~~- -. 4. Oil Line TO GWCK~W Wve GmrSbrb.h.ft 15. Turbochugor &r Train 5. Main Lube Oil and Pinon Cooling oil M M M d 18. Turbochuger B d n g Oil Supply Linw 6. Oil Pnuure Relief V&a 17. Oil Line to No. 1 Idler G u Stubohaft 18. M.in Oil Manifold 18. Oil Supply to Cnnkrhn M d Buringa Figure 6.1A Turbocharged Engine Lube Oil System 20. Piston Cooling oii Line Main Lubricating System The main lubricating oil system supplies oil under pressure to most of the moving parts of the engine. The main lube oil pump takes oil from the strainer housing at the right front of the engine. Oil from the pump goes into the main oil manifold which is located above the crankshaft, and extends the length of the engine. Maximum oil pressure is limited by a relief valve in the passage between the pump and the main oil manifold. Oil tubes at the center of each main bearing “A” frame conduct oil from the main manifold to the upper half of the main crankshaft bearings. Drilled passages in the crankshaft supply oil to the connecting rod bearings, torsional damper, and accessory drive gear at the front of the crankshaft. Leak-off oil from the adjacent main bearings lubricates the crankshaft thrust bearings. Oil from the manifold enters the gear train at the rear of the engine, at the idler gear stubshaft. Oil passages in the base of the stubshaft distribute the oil. One passage conducts oil upward to the left bank camshaft drive gear stubshaft bracket through a jumper, and downward to the lower idler gear stubshaft and bearing. Another passage conducts oil to the right bank camshaft drive stubshaft bracket and on to the turbocharger oil filter supply line. After passing through the filter, the oil enters the return line, returning to the upper idler gear stubshaft bore and bearing. Filtered oil enters the turbocharger oil system from the upper idler gear stubshaft. An oil pressure line connects to the top of the turbocharger oil manifold, adjoining the filter. This oil line goes to the low oil pressure device in the governor. I 6 2 ElectroMotive Model 567,645 & 710 Series Diesel Engines C u 0 3 3 19 0 9 19 3 3 3 3 3 19 3 3 3 3 9 3 3 3 3 9 3 9 3 ”) 3 3 9 ”) 3 3 3  Scavenging Oil System The scavenging oil system pump, takes oil through the scavenging oil strainer from the oil pan su~fipor reservoir. The pump then forces the oil through the oil filters and oil cooler which are located near the engine. Oil then returns to the strainer housing to supply the main lube oil pump and piston cooling pump with cooled and filtered oil Excess oil spills over a dam in the strainer housing and returns to the oil pan. Oil Gauge An oil level gauge, Fig. 6.2, extends from the side of the oil pan into the oil pan sump. The oil level should be maintained between the low and full marks on the gauge, with the reading taken when the engine is at idle speed and the oil is hot. Lubricating Oil Pressure Adequate lubricating oil pressure must be maintained at all times when the engine is running. Upon starting and idling an engine, it should be noted that (Ls the oil pressure builds up almost Figure 6.2 Oil Level Gauge immediately. In the event of cold 3 oil, the pressure may rise to the relief valve setting of approximately 125 psi 3 (862 P a ). Lubricating oil pressure is not adjustable. The operating pressure range is determined by such things as manufacturing tolerances, oil temperature, oil dilution, 3 wear, and engine speed. The pipe plug can be removed from the opening in the pump d discharge elbow and a gauge installed to determine the pressure. 3 The minimum oil pressure is approximately 8-12 psi (55.1 - 83 kPu) at idle and 25-29 psi ( I 72 - 200 kPu) at full speed. In the event of insufficient oil pressure, a G shutdown feature built into the governor will automatically protect the engine by shutting it down. Maximum pressure is determined by the relief valve setting of 125 psi 19..(862kPu)for 645 E3 and later engines, 60 p i (4!4 kPu) for 567 and 645E engines. --"u) b 3 Piston Cooling Oil Pressure d Pressure of the piston cooling oil will be governed by oil viscosity, speed of engine, 3 temperature of oil, and wear of pump parts. The pipe plug can be removed from the opening in the pump discharge elbow and a gauge installed to determine the pressure. 31 I 13; la4 ElectreMotive Model 567.645 & 710 Series Diesel Engines 4 s ' L I 1 c.-.,........ C c c Scavenging OiI Strainer (Coarse) c Figure 6.3 shows the G scavenging oil strainer (coarse) removed. The strainer is installed G in the housing and all oil for the G scavenging system is drawn through it. c The function of the strainer 6 is to protect the scavenging pump c from foreign material damage. Since the strainer is on the suction G side of the scavenging pump, improper application may cause G the engine to shut down for low lube oil pressure, usually under G load conditions. c Figure 6.3 Scavenging Oil Pump Strainer G Scavenging Oil Pump G The scavenging oil pump, Fig. 6.4, is a positive displacement, helical gear type c pump. The pump body, split transversely for ease of maintenance, contains sets of mated G pumping gears. The driving gears are retained on the pump drive gear shaft by Woodruff keys. G The idler shaft is held stationary in the housing by a set screw, and the driven c pump gears rotate on this shaft on bushings pressed into the gear bores. The drive shaft turns in bushings pressed into the pump body. G G These bushings are made with thrust collars which protrude slightly above the pump body and absorb the thrust G of the drive gears. The scavenging pump is mounted on the accessory G housing in line with, and to the left of the crankshaft, and is driven by C the accessory drive gear. c Design of the scavenging oil G pump is similar to the main lube oil and piston cooling oil pump, G except for the use of the spacer in the main oil pump. G G G Figure 6.4 Scavenging Oil Pump G G ITS Locomotive Training Series - Student Text asl c G - A  I u" 3 Pump Capacity (Approx. GPM) I 567 Engines at 835 rpm 130 190 9oot-P 279 I 710G3 Engines at 900 rpm 279 390 405 I - Lube Oil Filter Michiana Four & Seven Element Tanks Proper filtration of lubricating oil is essential to engine life and efficient, reliable operation. To fully realize the importance of adequate filter maintenance, it is helpful to understand the full flow lube oil system. Full flow filtration ensures that all the lubricating oil is filtered before it is supplied to the engine. A bypass valve is provided in the filter tank, however, and will open and bypass lube oil around the filter elements during conditions of cold oil start, or when filter elements are plugged. Figure 6.5 Lube Oil Filter Tank 6 Cooler The filter bypass valve ensures adequate lube oil to the engine, and prevents excessive scavenging oil pump outlet pressures. The valve opens at differential pressures above: *c.w- r., 1 6 30 psi (207 kPu) - 567 engine 40 psi (275 kPa) - 645 and 710 engines If lube oil filters become plugged, it is likely that the turbo filter will plug in short period of time and cause a low oil pressure shutdown of the engine. mas Electro-MotiveModel 567,645 & 710 Series Diesel Engines c 0 m E U (D 0 -I  Pump Capacity (Approx. GPM) 1 567 Engines at 835 rpm 130 190 II 71OG3 Engines at 900 mm 279 279 390 405 90 II - Lube Oil Filter Michiana Four & Seven Element Tanks Proper filtration of lubricating oil is essential to engine life and efficient, reliable operation. To fully realize the importance of adequate filter maintenance, it is helpful to understand the full flow lube oil system. Full flow filtration ensures that all the lubricating oil is filtered before it is supplied to the engine. A bypass valve is provided in the filter tank, however, and will open and bypass lube oil around the filter elements during conditions of cold oil start, or when filter elements are plugged. Figure 6.5 Lube Oil Filter Tank 6 Cooler The filter bypass valve ensures adequate lube oil to the engine, and prevents excessive scavenging oil pump outlet pressures. The valve opens at differential pressures above: cc -I. *. 30 psi (207 kPa) - 567 engine 40 psi (275 kPa) - 645 and 710 engines If lube oil filters become plugged, it is likely that the turbo filter will plug in short period of time and cause a low oil pressure shutdown of the engine. mas Electro-Motive Model 567, 645 & 710 Series Diesel Engines c 5, G G G Lube Oil Cooler G @ The oil cooler assembly, also shown in Figure 6.5, and c Figure 6.6 is representative of the late model installations, is positioned at an angle in the equipment rack adjacent to the G front end of the engine. C Q The external construction of the oil cooler consists of a G fabricated steel oil tank surrounding the oil cooler core. Inlet header assemblies are located near the top of the enclosure 8 c for entry of water to the upper radiator header. c The coolant returning c from the radiators enters the cooler through flanged G connections at the top of the cooler, flows through the c cooler tubes and is h \ P c discharged through flanged connections at the bottom of G the cooler. The lubricating oil enters c the shell space through a flanged connection near one G end of the cooler, flows G transversely around the tubes and around the end of the baffles, and leaves the shell through a flanged G connection near the opposite end of the cooler. The coolant and the oil flow through the cooler in c Figure 6.5A Fin and Tube Oil opposite directions to produce the maximum CooZer Cores cooling effect. c soldered left, c mechanically ToZZed right G Lube Oil Strainer Housing G C An oil level is maintained in the strainer housing up to the bottom of the overflow opening by the scavenging system. This oil serves as the supply for the main lube and G piston cooling systems. Excess oil not used by these systems returns to the engine sump. A spring loaded valve is provided to drain the oil from the strainer housing into the G engine sump for strainer maintenance. An additional valve is used to drain the oil filter c housing. Both of these valves are located under the filler cover. Normally oil is added to the engine by strainer housing. G C G l G G c - ITS LocomotiveTraining Series Student Text 6-7 I Ti  Main and Piston Cooling Oil Pump Strainers (Fine) One of the two main lube oil pump strainers is shown removed from housing, Figure 6.7. When in place, they are held by a crab and hand wheel on the stud between the holes. Each strainer is sealed at the top by a “0” ring seal. The engine lube oil strainers have oil pressure around the O-rings to assist in sealing. The oil under pressure will leak out under the strainer flanges if the seal rings are not sealed properly or are damaged. The current design two-piece main lube oil pump strainers each consist of a replaceable element of a pleated Figure 6.7 Main 6 Piston perforated metal core covered with mesh screening, and a Cooling Pump metal cylinder which encloses the element. Strainers This cylinder prevents collapse of the element in the event of a high pressure drop. The element is attached to the cylinder by a through bolt in the cylinder which runs through the base of the element and is secured with a locknut. The unperforated outer cylinder provides a constant head of oil since suction is from the bottom only and not through the entire length of the screen. Oil flow is from the bottom of the strainer between the cylinder and the mesh screen, through the mesh screen and the perforated metal core into the center of the element, then out the top of the strainer. Main Lube Oil and Piston Cooling Pump The main lube oil and piston cooling oil pumps shown in Figure 6.8, are contained in one housing. The two pumps are separated by a spacer plate between the sections of the pump body. Each has an individual oil inlet and discharge opening. Piston cooling pump gears at the end are narrower than the lube oil pump gears. The lube oil and piston cooling oil pump assembly is *“- mounted in the center of the accessory drive housing, and is driven by the accessory drive gear. B&8 ElectroMotive Model 567,645 & 710 Seriis Diesel Engines a G G c Pumps are designed and built in sections, to increase pump capacities for larger c horsepower engines. For example, the 567 main lube pump is equipped with only two helical gears, while the 6 4 5 and 710 main lube pumps are equipped with four c helical gears. c c Pump Capacity G c c I 5678835rpm 62 74 108 146 c I c 710 G3 8 900 rpm - 157 185 229 I c c Piston Cooling Oil Pump c 567 8 835 rpm 33 33 45 61 c c I 710G3 @ 900 rpm - 54 92 109 I c c c Lube Oil Pressure Relief Valve c The lube oil pressure relief valve c illustrated in Figure 6.9, is installed on the lube oil crossover manifold, inside the G accessory gear train housing on the left side of the engine. This valve is accessible for G inspection and service by removing the c Engine Protection Device, or access plate on engines not equipped with EPD. C The purpose of the valve is to limit the c; maximum pressure of the lube oil entering the engine oil system. G c When the lube oil pump pressure exceeds the spring tension on the valve, the G valve will be lifted off its seat and relieve the excess pressure. This oil drains into the tm* G accessory housing and then into the oil pan. Figure 6.9 Lube Oil G Pressure Relief Valve c c l?S Locomotive Training Series -Student Text 6-91 G 1  Turbocharger Oil Filter Description The turbocharger oil filter, Fig. 6.10, provides additional protection for the high speed bearings and other lubricated areas of the turbocharger, by filtering the oil just before it is admitted to the turbocharger. Oil enters the filter through a cast manifold and, after passing through the filter, returns to the upper idler gear stubshaft and into the turbocharger. The filter element is of pleated paper construction, and is disposable. The filter is mounted on the camshaft drive housing at the right bank of the engine. Newer engines have a disposable spin on type turbo lube filter. Always fill both types of filters with clean oil before installing on the engine. Figure 6.10 Turbocharger Oil Filter Soak Back Oil System To ensure lubrication of the turbocharger bearings prior to engine start, and the removal of residual heat from the turbo after engine shutdown, a separate lube oil pressure source is provided, refer to figure 6.1. This pressure system is controlled automatically by the locomotive control system. An electrically driven pump draws lube oil from the oil pan, pumps the oil through a filter and the head of the turbocharger oil filter directly into the turbocharger bearing area. The motor driven pump and filter are mounted on the side of the oil pan on the right bank of the engine. A 5 5 psi pressure relief valve, located in the head of the filter, controls the system pressure. Also located in the filter head is a bypass valve set for 70 psi. This valve will open to permit oil from the soak back pump to bypass a filter element so lubrication can be supplied to the turbocharger to prevent turbo damage. Soak Back Filter Pressure Switch Some engines are equipped with a soak back filter pressure switch that will inhibit starting of the diesel engine until the turbo lube system is pressurized. II6-10 ElectmMotive Model 567, 645 & 710 Series Diesel Engines ’L  3 3 3 3 3 5 3 3 3 3 9 9 a 3.- 3  3 Lube Oil Separator (Turbo, Air Ejector System) 3 3 In applications that cause back pressure in the 3 exhaust system, such as exhaust silencers or extended 3 exhaust piping runs, an air 3 ejector system is used to increase crankcase vacuum. u Pressurized air from the e3 left bank aftercooler duct is piped to the ejector, where it IJ, blows through a venturi, o*u) adding to the suction created by the eductor tube. Different 0 size ejector nozzles are available to aid in maintaining 3 proper crankcase suction levels. To increase crankcase 3 suction, apply a large diameter 3 Figure 6.13 Ejector System nozzle, but only after inspecting the engine for other causes of low vacuum. Oil droplets collect in the lube oil 3 separator, and drain back to the crankcase, while the vapors discharge into the exhaust and are vented to the atmosphere. d 3 SYSTEM MAINTENANCE Y) Maintenance of the lube oil system normally consists of a few minor tasks performed as part of a scheduled maintenance program, however there are certain * additional tasks that may be required when unscheduled repairs are performed or the 3 unit has been stored. kll Always consult your company's maintenance instructions for specific inspection items and frequency. * 3 SCHEDULED MAINTENANCE 3 kd Daily or Trip 3 The lube oil level should be checked frequently to ensure that the engins has an adequate supply for lubrication and cooling. Low oil levels can lead to high oil u temperatures as well as low oil pressure. Visually check the dip stick on the right bank of rcI;) the engine to ensure that the oil level is at or near the full mark. Also note the presence of: d Fuel vapours that could indicate internal fuel leaks; 3 Grey sludge that could indicate internal water leaks. -0 13 I612 Eiectro-Motive Model 567.645 & 710 Series Diesel Engines L) 'L LA c G c 6 If oil must be added, ensure that the fluid meets the specifications for lubricating c oils set out in Maintenance Instruction 1752. Oil is added to the diesel engine through the fill port located above the main water pump (front right corner). Ensure that the area c; is clean before opening the cap and replace securely when finished. Record the amount of oil added as a high consumption rate may indicate serious engine problems. 6 Visually examine the system for any signs of leakage. c G 90 Day Inspection 42 In addition to oil level, the condition of the oil must be checked for any c indications of problems with the internal engine components. The oil is to be checked for: G Total dirt load (filtration) C e TBN (total base number) c;* Free water (internal water leaks) C Trace elements (internal wear or component failure) c Sodium andlor boron (internal water leaks) c Viscosity (internal fiel leaks) c Take a sample of engine oil for analysis from the test fitting located at the main c lube pump. Ensure that a clean container is used for the sample to avoid incorrect test results. Follow the recommendations of Maintenance Instruction 1752 for the specific c condemning limits of the lubricating oil and any recommended checks or tests if c unusual results are found. c At 90 days, the main oil filters should be renewed. With the engine shut down, open the lube oil filter tank drain valve and allow the oil to drain back into the engine c sump before opening the access doors. Remove the filter elements, thoroughly clean the tanks and renew the 8 paper elements. Apply new seals and secure the access doors. c Note: Do not forget to close the filter tank drain valve! c, The turbo lube and soak back filters are also renewed on the 90 day inspection. c; Pre-fill both elements with clean engine lube oil before applying to the engine. This procedure has not been altered from previous design engines. c The strainer housing has been replaced on this engine by a single strainer element 6. located on the front of the diesel engine beside the main lube pump. Remove the CSI strainer cover and withdraw the element from the housing. Inspect the element and the bottom of the housing for debris, clean as required. Reapply the strainer element and c cover using a new gasket. a G c CJ TTS Locomotive Training Series -.StudentText b1,3 a G  On an annual basis the following additional check should be made to ensure proper operation of the lube oil system. Open the left rear crankcase inspection cover and the rear top deck covers. Initiate the turbo lube pump sequence and ensure proper system operation. With the pump running, there should be a steady flow of lube oil returning to the engine sump down the rear gear train housing. There should be no oil flow from the crankshaft or camshafts. Oil flow in this area would indicate faulty check valves in the turbo filter head. Remove the filter head and service check valves as required. Specific instructions may be found in the Engine Maintenance Manual. 2 Year Inspection After the locomotive has been in service for 2 years, the temperature differential between the lube oil and cooling water entering the engine should be checked. If the differential is outside the prescribed service limits indicated in MI 928, the cooler will have to be cleaned or replaced with a qualified unit. Note that this check is performed as part of a load test. 3 Year Inspection On the 3 year inspection, remove the main lube oil filter bypass valve. Clean, inspect and test the valve before reinstalling. The procedures for servicing this valve may be found in MI 926. Remove the turbo lube filter head assembly, clean, inspect and qualify the check valves as per the procedures indicated in the Engine Maintenance Manual. Ensure that the system is checked for proper operation before returning the locomotive to service. 6 Year Inspection The 6 year inspection is the major inspection interval. This inspection will require the removal of the main lube oil pump and oil pressure relief valve. Replace these components with qualified units. Remove, clean and inspect the soak back filter head assembly. Pay close attention to the bypass ball valves, replace if required. Remove and recondition soak back pump and motor. Check system operation before dispatching locomotive. Lube Oil System Troubleshooting Problems with the lube oil system generally can be classed as one of two types; (1) a loss of oil pressure or (2) high oil temperatures. b 6.14 - ElectrMotive Model 567, 645 & 710 Series Diesel Engines c c G G Low Oil Pressure - Non EMDEC G Engine lube oil pressure is determined by manufacturing tolerances, oil c temperature, oil condition, engine wear, and engine speed. Minimum oil pressure is 8- c 12psi (55-83kPu)at idle, and 25-29psi at full speed. If oil pressure falls below these levels, the low lube oil shutdown on the Woodward governor will shut the engine down. c Low lube oil shutdown by the governor is also initiated by the hot oil detector, E.P.D. low cooling water portion, or E.P.D. crankcase pressure portion. When an engine is c reported as having low oil pressure, the following steps should be taken: G Check the engine lube oil level, add oil if low. c Take a lube oil sample to check for proper oil viscosity. Low oil viscosity c caused by a condition such as internal fuel leakage will have a dramatic negative effect on oil pressure. Follow directions on page4-20 for finding c internal fuel leaks. G Note the engine water and oil temperature. As with fuel leaks, a high oil c; temperature will lower the oil's viscosity and therefore the oil pressure. Should the oil temperature be above a normal range, qualify the cooling c system, the lube oil cooler efficiency and perform an internal inspection of the engine sump looking for signs of overheating, and loose or c missing components. c Remove the 314" pipe plug in the main lube oil pump discharge elbow and c install a 0 - 150 PSI test oil gauge in the outlet elbow of the main lube oil pump. If the oil pump pressure is low, proceed with the following checks. c If the pump pressure is adequate, proceed to "Test gauge reading adequate". CI Remove and clean the two fine screen strainers in the strainer housing. G Inspect the seals and blow compressed air through the seal vent line to G make sure it is not obstructed. Drain the strainer housingusing the strainer housing drain valve and inspect for foreign material. e Check for suction leaks at the flanges of the main lube oil pump inlet G elbow at both the pump and strainer housing ends. Replace gaskets where necessary. 6 c Change the turbocharger oil filter element. A clogged or upside down element cancause low oil pressure in the line to the governor, causing the c engine to shut down. G Remove the Engine Protection Device from the engine, (ifequipped), c leaving the oil lines connected, and move it to the side. Check the oil pressure relief valve for excessive oil leakage from the relief port indicating c the valve is stuck in the open position. If so, remove the oil pressure relief valve and replace it with a qualified unit. Also check for excessive lube oil - c flow from any other source. G c c ITS LocomotiveTraining Series -Student Text &15 I G  Remove all crankcase covers and inspect the piston pins and external surfaces of the main and connecting rods for signs of overheating and missing or loose components. If nothing is found in the above checks, remove and qualify the main lube oil pump 1 Test gauge reading adequate: Remove and qualify the main engine oil pressure gauge or replace it 3j with aqualified unit. Check the 1/8" diameter oil supply line in the right bank top deck of the engine for damage and blow air through it to make sure it is clear of obstructions. Disconnect and block the connecting line from the oil pressure sensing line to the Engine Protection Device and hot oil detector. Start the engine, if oil pressure is restored, either the EPD or hot oil detector is defective. Remove and qualify both devices as per instructions in the Engine Maintenance Manual. Use the recommended tool and procedure in the EMM to check the clearance of the Number 1 idler stubshaft bushing. Excessive clearance will cause a low pressure reading. Inspect the interior of the end housing for debris under the rear gear train. On turbo engines, remove the auxiliary generator drive (OT cover prate i f not equipped), and check the manifold to the turbo filter for cracks,loose or missing components or seals. Inspect the camshaft supply manifolds, and ensure that the upper pipe plug is installed in the gauge line connecting block. On blower engines, remove the auxiliary generator drive (OT oil separator housing if not equipped). Inspect the oil jumper lines to the camshaft bearing brackets for loose or missing components or seals. 3 3 6-16 Electro-Motive Model 567, 645 & 710 Series Diesel Engines L) -L u G c;J G Low Oil Pressure - EMDEC G Engine lube oil pressure and temperature is constantly monitored by the EMDEC c control unit through the use of the pressure sensor located at the turbo filter head and the temperature probe located at the main oil inlet on 8,12, and 16 cylinder engines, L and the oil inlet "Y" pipe on 20 cylinder engines. This information is relayed also to the G EM2000 for display on the screen. Should either condition move outside of normal operating ranges, EMDEC will cause an engine shutdown and display a fault condition, c Thus EMDEC performs the function of the low lube oil shutdown on the Woodward governor and the function of the hot oil detector on older engines. When an engine is C reported as having low oil pressure, the following steps should be taken immediately: G 0 Take a lube oil sample to check for proper oil viscosity. Low oil c viscosity caused by a condition such as internal fuel leakage will have a dramatic negative effect on oil pressure. c Determine whether the problem is actually low pressure, or an G incorrect reading by the pressure transducer. Fit a mechanical gauge c to the pressure sensor location using a "Tee" fitting. When the engine is operating, the gauge and the reading indicated by the c sensor should be within a few pounds of each other. If not, replace the sensor with a qualified unit. c Note the engine water and oil temperature. As with fuel leaks, a high c oil temperature will lower the oil's viscosity and therefore the oil c pressure. Should the oil temperature be above a normal range, qualify the cooling system, the lube oil cooler efficiency and perform G an internal inspection of the engine sump for possible bearing distress. G If the mechanical gauge indicates a true low pressure situation, the procedures for C qualifying the system remain the same as in the past, however, note closely the G condition of the following: c Suction strainer cover gasket. c Pressure differential across the main lube filters. c Position of lube oil filter drain valve. C Inlet pressure to engine at "Y" pipe. CL Condition of piston cooling pipes. G It is very easy to break the system down into specific areas by simply looking at the c pressure of the oil leaving the main lube pump, entering the engine, and at the turbo G filter head. For example, if there is little pressure leaving the main pump, then the problem is likely on the suction side of the pump or the pump itself. Further, if the G pressure drops dramatically across the filters, then one would suspect a problem in th'is area. G G c ITS Locomotive Training Series -Student Text 617 a G.. 3 Lack of Oil Delivery From Scavenging System The first step in troubleshooting the scavenging oil system is to install a 0 - 50 PSI pressure gauge in the quick disconnect fitting on the Michiana filter tank. Prelube the engine if necessary. This procedure is for all installations except marine engines with engine mounted raw water pumps. Before starting the engine: Check engine oil level. Ensure the strainer housing is full to within 5 lmm (2") of the screen under the large cover. Make sure the Michiana tank drain valve (Thandle) is fully closed. Remove and clean the scavenging pump course strainer element which is held in the strainer box by three bolts. Check the interior of the strainer housing for foreign material and clean if necessary. Reinstall the clean strainer element in the housing with a new gasket, and tighten securely. Remove the crankcase covers at the right front of the engine and inspect the full length of the scavenging oil suction line from the front end of the engine to the oil sump for cracks or mechanical damage from broken connecting rods or pistons. Repair any damage before starting engine. After starting the engine, check to see if the oil level in the strainer box returns to approximately 51 mm (2") of the screen within 45 seconds. If it does not, take a pressure reading at the Michiana tank with the engine at idle and do the following checks. If the strainer box does refill, proceed to checks under "Strainer Box Refills". If the pressure reading was low or zero, either the scavenging pump is defective or there is a suction leak in the suction line to the strainer box. Remove and overhaul scavenging pump if necessary. If the pressure reading was higher than 69 kPa (IOpsi),change the oil filter elements, then repeat the test. If the pressure is still over 69 kPa (IOpsi), remove and clean the oil cooler. Strainer Box Refills If the strainer box refills, slowly increase engine RPM to full speed. At full speed take a reading of the gauge on the Michiana tank. If the pressure reading is above 172kPa (25psi),change the filter elements. O n switcher locomotives and industrial engines with tube bundle and shell type oil coolers, the changeout pressure reading is 172 P a (SO psi). Take the pressure reading again. If the pressure is 69kPa (lopsi) switcher - industrial 138kPa [20 psi] or more, temperature test the oil cooler using the procedure in "High oil Temperature" section. If indicated, remove and clean the oil cooler. I618 ElectroMotive Model 567,645 81710 Series Diesel Englnes G c( 0 If the pressure reading is 2lkPa (3psi) switcher - industrial 69kPa [ 10 psi], ci remove the bypass valve from the Michiana tank and determine if it is jammed open. c e High Oil Temperature r G WARNING: c When an engine shuts down due to hot oil, wait at least 2 hours before attempting to inspect the engine. Opening engine covers and admitting fresh G 'It @,f I 8 ," air when the oil vapours inside the engine are hot could cause an explosion. Follow these suggested steps to find the cause of a hot oil shutdown. G c Check oil level in the oil pan and monitor oil pressure on the engine lube c oil pressure gauge c Verify that there is delivery of oil from the scavenging oil system (See Lack of delivery fiom scavenging system). G e Determine if there is a high cooling water temperature problem, as high cooling water temperature will cause high oil temperature. (See Chapter 5 c for cooling system troubleshooting). c If the engine is equipped with a thermostatic temperature control valve c (marine and stationary power upplications), verify the opening of the valve. Failure of the valve to open can deprive the oil cooler of cooling water. c Temperature test the oil cooler by installing temporary thermometers in the c wells provided in the cooling water piping. Run the engine and monitor temperatures in and out of both the oil and water sides of the oil cooler. G Compare these readings with a standard chart on locomotive installations, c or installation records on marine and stationary power. If oil temperature drop or coolant temperature rise values are not adequate, remove the oil c cooler for inspection and cleaning ( i f necessary). c Remove all crankcase covers and inspect for signs of overheated surfaces or e extruded bearing material around the main and connecting rod bearings. Inspect under the front and rear gear trains for metal debris. G G High Oil Temperature EMDEC - C Normally there is a close relationship between engine coolant temperature and engine lube oil temperature. EMDEC monitors lube oil temperature as the oil enters G the engine. If the temperature of this oil exceeds approximately 124" C (255"F), c EMDEC will cause an engine shutdown and communicate the fault to the EM2000 control computer. G G G c ITS LocomotiveTraining Series -Student Text 619 a c -IL c G 0 Replace any defective components, then load test the engine. If oil loss continues, C proceed with the following checks: E Disassemble the lube oil separator and check for a missing or disintegrated screen. Replace if missing. The absence of this screen can cause excessive G oil consumption and oil out the stack. Loss of crankcase vacuum due to c combustion gases from a cracked piston, pressurized air box air via bad lower liner seals, or ambient air through a loose crankcase cover can cause a c flow rate that exceeds the separator screens' ability to filter out oil droplets. Check crankcase vacuum with a manometer and correct any defective c conditions found. G Remove the turbocharger screen and inspect the exhaust manifold for G manifold legs coated with oil. Change the power assembly or assemblies in the cylinders indicated by the oil coated manifold legs. If the exhaust stack c is excessively covered in oil so it is impossible to tell which cylinder the oil is coming from, in may be necessary to load test the engine to dry out the c exhaust manifold, then repeat the check. e If no oil is found in the exhaust manifold, the problem is most likely in the C turbocharger. Check the turbo air intake filters for signs of plugging. Plugged filters can cause high inlet vacuum and draw oil past the turbocharger labyrinth seals. See the c Turbocharger section of this manual for the procedure to qualify a turbo for changeout. (1. Worn or pounded head retainer surfaces, or pounded head seat rings due to improperly torqued head crab nuts can create clearance which allows oil to c be drawn past the head seat ring and into the exhaust. These conditions can c be minimized by following the appropriate Scheduled Maintenance program for checking crab nut torques, and by following proper crab nut G torquing procedures when changing power assemblies. ci Engines operated for extended periods of time under light or no load may c experience varnishing, (light brown or tan deposits) of the cylinder walls. This condition reduces the effectiveness of the oil rings and can lead to a c condition called "souping'l, or oil loss out the exhaust. If light load operation is continued, the varnish deposits can interfere with the ring to liner seal c effectiveness. To remove these deposits it may be necessary to load the engine by either a change of service or the use of a load box to remove c the deposits. G G 6 G G G G G c ITS LocomotiveTraining Series -Student Text 621 a 0  Prelubrication of Engines Prelubrication of a new engine, an engine that has been overhauled, or an engine which has been inoperative for more than 48 hours is a necessary and important practice. Prelubrication alleviates loading of unlubricated engine parts during the interval when the lube oil pump is filling the passages with oil. It also offers protection by giving visual evidence that oil distribution in the engine is satisfactory. Perform prelubrication as follows: 1. Remove the pipe plug at the main lube oil pump discharge elbow, and connect an external source of clean, warm oil at the discharge elbow. Prelube engine at a minimum of 69 kPa (1Opsi) for a period of not less than three and not more than five minutes (approximately 57 lpm or 15 gpm) using a 1.1 to 1.5kW (1.5 to 2 hp) motor. 2. While oil pressure is being applied, open the cylinder test valves and bar the engine over one complete revolution. Check all bearings at the crankshaft, camshafts, rocker arms, and at the rear gear train for oil flow. Also check for restrictions and excessive oil flow. If fluid discharge is observed from any cylinder test valve, find the cause and make the necessary repairs. 3. On new or overhauled engines, remove the pipe plug at the piston cooling oil pump discharge elbow and connect the external oil source at that opening. Check for unrestricted oil flow at each piston cooling oil pipe. 4. Disconnect the external oil source and replace the pipe plugs at the pump discharge elbows. Close the cylinder test valves. 5. Pour a liberal quantity of oil over the cylinder head mechanisms of each bank. 6. Check oil level in the strainer housing and, if required, add oil to the strainer housing until it overflows into the oil pan. 7. Replace and securely close all handhole covers and engine top deck covers. When an engine is replaced due to mechanical breakdown, it is important that the entire oil system, such as oil coolers, filters, and strainers, be thoroughly cleaned before a replacement engine or reconditioned engine is put in service. A recurrence of trouble may be experienced in the clean engine if other system components have been neglected. In some cases engines have Sezz rcnoved from service and stored in the "as is" condition by draining and applying anti-rust compound. When these engines are returned to service, care must be taken to see that any loose deposits are flushed out before adding a new oil charge. The entire engine should be sprayed with fuel to break up any sludge deposits, and then drained, being careful that the drains are not plugged. Fuel should not be sprayed directly on the valve mechanism or bearings, as lubrication will be removed or dirt forced into these areas. The surfaces should be wiped dry before new oil is added to the engine. I622 Electro-Motive Model 567, 645 & 710 Series Diesel Engines r3