Abstract:
A system for lubricating an engine is disclosed. In one example, the system includes an oil purging passage in fluidic communication with an oil gallery within an engine block. The system may provide for reduced engine degradation related to debris that may be found in engine oil.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application is a continuation of U.S. patent application Ser. No. 13/344,549, “ENGINE LUBRICATION SYSTEM,” filed on Jan. 5, 2012, the entire contents of which are hereby incorporated by reference for all purposes. 
     
    
     BACKGROUND/SUMMARY 
       [0002]    Debris may be present in the oil within an engine during engine assembly. The debris may enter the engine from the external environment or from machining during engine manufacturing. For example, metal flakes and other debris produced during manufacturing of engine lubrication passages and other engine parts may enter the oil. Some engine lubrication systems are structured such that the debris may pass through various components such as cam phasers, valve adjusters (e.g., lash adjusters), bearings, tensioners, pistons, etc., before entering an oil filter where the debris may be removed from the oil. Therefore, during start-up of a “green” or new engine, unfiltered oil that includes debris may flow into the aforementioned components. As a result, the engine components may degrade, and the degraded components may degrade operation of the engine. An example of an engine lubrication system including a cam phaser positioned downstream of an oil filter and an oil pump is described in U.S. Patent Publication No. 2005/0061289. 
         [0003]    The inventors herein have recognized the above-mentioned disadvantages of a closed lubrication system and have developed an engine lubrication system, comprising an engine block including an oil gallery passage extending through the engine block and supplying oil to a group of one or more moveable engine components, the oil gallery passage supplied oil from an oil pump, the oil gallery passage in fluidic communication with a drainage passage, and a movable stopper positioned in the drainage passage that selectively bypasses oil from the oil pump to an oil reservoir. 
         [0004]    By bypassing engine oil around hydraulically operated devices and lubricated components of an engine before an engine is first operated, it may be possible to reduce engine component degradation. Specifically, the bypassed engine oil can be returned to an oil reservoir with the debris, and the debris can be filtered from the oil before the oil is used to lubricate engine components and operate hydraulic actuators. After debris is flushed from engine lubricating passages, the oil bypass passages may be closed so that oil is directed to engine components and hydraulically actuated devices. 
         [0005]    The present description may provide several advantages. Specifically, the approach may reduce engine component degradation by allowing debris to be removed from engine oil before the engine oil passes through the components being lubricated. Further, the approach allows debris to be flushed from the interior of an engine without having to remove cylinder heads or crankshaft components. Further still, the approach provides quick access to engine oil passage flow regulating devices so that once the debris is flushed from oil passages, oil can be directed to engine components for lubrication and activation. 
         [0006]    The above advantages and other advantages, and features of the present description will be readily apparent from the following Detailed Description when taken alone or in connection with the accompanying drawings. 
         [0007]    It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0008]      FIG. 1  shows a schematic depiction of an engine; 
           [0009]      FIG. 2  shows a schematic depiction of a lubrication system in an engine assembly; 
           [0010]      FIGS. 3 and 4  show isometric views of an engine assembly according to an example of the disclosure; 
           [0011]      FIGS. 4-10  show cross-sectional views of the engine assembly illustrated in  FIGS. 3 and 4 ; and 
           [0012]      FIG. 11  shows a method for operation of a lubrication system. 
           [0013]      FIGS. 2-10  are drawn approximately to scale. 
       
    
    
     DETAILED DESCRIPTION 
       [0014]    A lubrication system for draining an engine of oil prior to full assembly of the engine is described herein. The lubrication system may include an oil gallery passage having a drainage opening positioned near an end of the oil gallery passage. The opening may be un-sealed prior to a selected stage in an engine assembly process. While the oil gallery passage is unsealed, oil may flow through the oil gallery passage and into a drainage opening. The drainage opening may be in fluidic communication with an oil reservoir. Thus, engine oil can be pumped through the engine oil gallery passage to clear debris from the engine and oil. In this way, the engine lubrication system may be flushed prior to final engine assembly. The drainage opening is sealed after debris is flushed from the engine lubrication passage. The drainage opening may be sealed via a passage stopper positioned within the drainage opening itself or it may be sealed via a passage stopper inserted into the end of the oil gallery passage axially extending across the drainage opening. 
         [0015]    Referring to  FIG. 1 , internal combustion engine  10 , comprising a plurality of cylinders, one cylinder of which is shown in  FIG. 1 , is controlled by electronic engine controller  12 . Engine  10  includes combustion chamber  30  and cylinder walls  32  with piston  36  positioned therein and connected to a crankshaft  40 . Combustion chamber  30  is shown communicating with intake manifold  44  and exhaust manifold  48  via respective intake valve  52  and exhaust valve  54 . Each intake and exhaust valve may be operated by an intake cam  51  and an exhaust cam  53 . Alternatively or additionally, one or more of the intake and exhaust valves may be operated by an electromechanically controlled valve coil and armature assembly. The position of intake cam  51  may be determined by intake cam sensor  55 . The position of exhaust cam  53  may be determined by exhaust cam sensor  57 . 
         [0016]    Fuel injector  66  is shown positioned to inject fuel directly into cylinder  30 , which is known to those skilled in the art as direct injection. Alternatively, fuel may be injected to an intake port, which is known to those skilled in the art as port injection. Fuel injector  66  delivers liquid fuel in proportion to the pulse width of signal FPW from controller  12 . Fuel is delivered to fuel injector  66  by a fuel system (not shown) including a fuel tank, fuel pump, and fuel rail (not shown). Fuel injector  66  is supplied operating current from driver  68  which responds to controller  12 . In addition, intake manifold  44  is shown communicating with optional electronic throttle  62  which adjusts a position of throttle plate  64  to control air flow from intake boost chamber  46 . In other examples, the engine  10  may include a turbocharger having a compressor positioned in the intake system and a turbine positioned in the exhaust system. The turbine may be coupled to the compressor via a shaft. A high pressure, dual stage, fuel system may be used to generate higher fuel pressures at injectors  66 . 
         [0017]    Distributorless ignition system  88  provides an ignition spark to combustion chamber  30  via spark plug  92  in response to controller  12 . Universal Exhaust Gas Oxygen (UEGO) sensor  126  is shown coupled to exhaust manifold  48  upstream of catalytic converter  70 . Alternatively, a two-state exhaust gas oxygen sensor may be substituted for UEGO sensor  126 . 
         [0018]    Converter  70  can include multiple catalyst bricks, in one example. In another example, multiple emission control devices, each with multiple bricks, can be used. Converter  70  can be a three-way type catalyst in one example. 
         [0019]    Controller  12  is shown in  FIG. 1  as a conventional microcomputer including: microprocessor unit  102 , input/output ports  104 , read-only memory  106 , random access memory  108 , keep alive memory  110 , and a conventional data bus. Controller  12  is shown receiving various signals from sensors coupled to engine  10 , in addition to those signals previously discussed, including: engine coolant temperature (ECT) from temperature sensor  112  coupled to cooling sleeve  114 ; a position sensor  134  coupled to an accelerator pedal  130  for sensing accelerator position adjusted by foot  132 ; a knock sensor for determining ignition of end gases (not shown); a measurement of engine manifold pressure (MAP) from pressure sensor  122  coupled to intake manifold  44 ; an engine position sensor from a Hall effect sensor  118  sensing crankshaft  40  position; a measurement of air mass entering the engine from sensor  120  (e.g., a hot wire air flow meter); and a measurement of throttle position from sensor  58 . Barometric pressure may also be sensed (sensor not shown) for processing by controller  12 . In a preferred aspect of the present description, engine position sensor  118  produces a predetermined number of equally spaced pulses every revolution of the crankshaft from which engine speed (RPM) can be determined. 
         [0020]    In some examples, the engine may be coupled to an electric motor/battery system in a hybrid vehicle. The hybrid vehicle may have a parallel configuration, series configuration, or variation or combinations thereof. Further, in some examples, other engine configurations may be employed, for example a diesel engine. 
         [0021]    During operation, each cylinder within engine  10  typically undergoes a four stroke cycle: the cycle includes the intake stroke, compression stroke, expansion stroke, and exhaust stroke. During the intake stroke, generally, the exhaust valve  54  closes and intake valve  52  opens. Air is introduced into combustion chamber  30  via intake manifold  44 , and piston  36  moves to the bottom of the cylinder so as to increase the volume within combustion chamber  30 . The position at which piston  36  is near the bottom of the cylinder and at the end of its stroke (e.g. when combustion chamber  30  is at its largest volume) is typically referred to by those of skill in the art as bottom dead center (BDC). During the compression stroke, intake valve  52  and exhaust valve  54  are closed. Piston  36  moves toward the cylinder head so as to compress the air within combustion chamber  30 . The point at which piston  36  is at the end of its stroke and closest to the cylinder head (e.g. when combustion chamber  30  is at its smallest volume) is typically referred to by those of skill in the art as top dead center (TDC). In a process hereinafter referred to as injection, fuel is introduced into the combustion chamber. In a process hereinafter referred to as ignition, the injected fuel is ignited by known ignition means such as spark plug  92 , resulting in combustion. During the expansion stroke, the expanding gases push piston  36  back to BDC. Crankshaft  40  converts piston movement into a rotational torque of the rotary shaft. Finally, during the exhaust stroke, the exhaust valve  54  opens to release the combusted air-fuel mixture to exhaust manifold  48  and the piston returns to TDC. Note that the above is described merely as an example, and that intake and exhaust valve opening and/or closing timings may vary, such as to provide positive or negative valve overlap, late intake valve closing, or various other examples. 
         [0022]      FIG. 2  shows a schematic depiction of an engine assembly  200  including a lubrication system  202 . It will be appreciated that engine  10 , shown in  FIG. 1 , may be included in the engine assembly  200  shown in  FIG. 2 .  FIG. 2  depicts various components spaced apart for visual clarity. However, it will be appreciated that the components may be adjacent to one another. The engine assembly includes a cylinder block  201  and a first cylinder head  228  and a second cylinder head  268 . The lubrication system  202  is configured to flow oil therethrough. It will be appreciated that the oil may be a synthetic oil, a non-synthetic oil, a bio-lubricant, a synthetic oil blend, or other suitable lubricant. Arrows  204  denote the general flow of lubricant through the lubrication system  202 . However, it will be appreciated that the flow pattern of the lubricant in the lubrication system  202  may have additional complexity that is not illustrated. 
         [0023]    The lubrication system  202  includes an oil reservoir  206  configured to hold oil or other suitable lubricant. A pick-up line  208  may be positioned in the oil reservoir  206  and includes an inlet  210  configured to receive oil from the oil reservoir  206 . The pick-up line  208  further includes an outlet  212  in fluidic communication with the inlet  210  of a pump  214 . The pump  214  may be configured to supply oil to components in the engine  10 . The pump  214  is configured to generate a pressure head to enable the flow of oil to downstream components in the lubrication system  202 . An oil filter  216  may be located directly downstream of the pump  214  in a series flow configuration. Therefore, a first passage in a series flow configuration has an outlet in direct fluid communication with an inlet of a second passage. It will be appreciated that the inlets or outlets of the two passages are not in direct fluidic communication in a series flow configuration. An oil filter supply component  218  may be positioned upstream of and in fluidic communication with the oil filter  216  configured to supply oil to and receive oil from the oil filter  216 . Although in some examples, the oil filter supply component  218  may be part of the oil filter  216 . The oil filter  216  may be configured to remove particulates from the oil. The outlet of the oil filter  216  is in fluidic communication with supply oil passage  220 . Specifically, the oil filter supply component  218  provides a fluidic communication passage from oil filter  216  to supply oil passage  220 . 
         [0024]    The supply oil passage  220  supplies oil to a valley oil gallery passage  222  and a first oil gallery passage  224  and a second oil gallery passage  226  include in a first cylinder head  228 . In particular, an oil passage  230  branches off from the supply oil passage  220 . As shown, the first and second oil gallery passages ( 224  and  226 ) longitudinally extend through the first cylinder head  228 . Additionally, the oil passage  230  is in fluidic communication with the first and second oil gallery passages ( 224  and  226 ) in a first cylinder head  228 . It will be appreciated that the first cylinder head  228  may be coupled to the cylinder block  201  to form a cylinder bank. A cam cover may be coupled to the first cylinder head  228 . The valley oil gallery passage  222  includes a drainage opening  229 . The drainage opening may be sealed when the engine assembly  200  is a complete assembly. The valley oil gallery passage  222  is in fluidic communication with the oil reservoir  206  when the drainage opening  229  is unsealed. Therefore, it will be appreciated that the drainage opening  229  may be unsealed and configured to return oil to the oil reservoir  206  during engine construction when the engine assembly  200  is partially assembled. The drainage opening  229  may be unsealed when the engine is not combusting an air-fuel mixture. The drainage opening  229  is depicted via a generic box in  FIG. 2 . However, the geometric characteristics of the drainage opening  229  are illustrated in more detail in  FIG. 6 . 
         [0025]    The first oil gallery passage  224  and the second oil gallery passage  226  included in the first cylinder head  228  are configured to supply oil to a plurality of moveable engine components  232  in a camshaft assembly. The moveable engine components  232  may include hydraulically operated devices. 
         [0026]    Although a plurality of moveable engine components are depicted, it will be appreciated that in other examples, the first oil gallery passage  224  may be configured to supply oil to a single engine component. Moreover, it will be appreciated that the first oil gallery passage  224  may supply oil to components associated with intake valves and the second oil gallery passage  226  may supply oil to components associated with exhaust valves or vice-versa. 
         [0027]    The moveable engine components  232  include cam phasers  234 , valve adjusters (e.g., lash adjuster)  236 , camshaft bearings  238 , and/or a tensioner  240 . The cam phasers  234  may be configured to alter the intake and/or exhaust valve timing. The valve adjusters  236  may be configured to actuate intake and/or exhaust valves. The camshaft bearings  238  may be configured to lubricate rotation of the intake and/or exhaust camshafts schematically depicted at  241  and  243 . The tensioner  240  may be coupled to a cam driver (e.g., chain). The cam driver may be rotatably coupled to one or more of an intake camshaft, exhaust camshaft, and/or a crankshaft. The tensioner  240  may be configured to increase the tension of the cam driver. 
         [0028]    The first oil gallery passage  224  includes an inlet  242  that is in fluidic communication with oil passage  230 . The first oil gallery passage  224  includes a drainage opening  246  that is sealed when the engine assembly  200  is assembled. The drainage opening  246  may be unsealed and configured to return oil to the oil reservoir  206  during engine construction when the engine assembly  200  is partially assembled and/or the engine is not combusting an air-fuel mixture. In this way, the first oil gallery passage  224  may be flushed of any unwanted particulates in the lubrication system  202  during engine construction. 
         [0029]    The oil passage  230  is also in fluidic communication with inlet  248  of the second oil gallery passage  226  included in the first cylinder head  228 . As previously discussed, the second oil gallery passage  226  may be configured to supply oil to the moveable engine components  232 . 
         [0030]    The second oil gallery passage  226  also includes a drainage opening  247  that is sealed when the engine assembly  200  is assembled. The drainage opening  247  is in fluidic communication with the oil reservoir  206  when the passage is unsealed. Therefore, it will be appreciated that the drainage opening  247  may be unsealed and configured to return oil to the oil reservoir  206  during engine construction when the engine assembly  200  is partially assembled. The drainage opening  247  may be unsealed when the engine is not combusting an air-fuel mixture. The drainage openings ( 246  and  247 ) are schematically depicted via generic boxes in  FIG. 2 . However, the geometric characteristics of the drainage openings are illustrated in detail in  FIG. 7 . 
         [0031]    The supply oil passage  220  is also in fluidic communication with valley oil gallery passage  222 . Specifically, the valley oil gallery passage  222  is in fluidic communication with outlet  252  of the supply oil passage  220 . As shown, the valley oil gallery passage  222  includes an inlet  254 . The inlet  254  is positioned near a front engine cover engaging surface  304  shown in  FIG. 3 , discussed in greater detail herein. The valley oil gallery passage  222  is also in fluidic communication with a plurality of moveable engine components  256 . The moveable engine components  256  may include hydraulically operated devices. The moveable engine components  256  include piston jets  258  and the bearings enclosed by the bearing caps  260 . It will be appreciated that crankshaft bearings may be positioned within the bearing caps  260 . The bearing caps  260 , the crankshaft bearings, and the crankshaft may all be included in a crankshaft assembly. The piston jets  258  may be configured to spray oil onto pistons included in the first and/or second cylinder heads ( 228  and  268 , respectively). 
         [0032]    An oil passage  262  is in fluidic communication with the valley oil gallery passage  222 . The oil passage  262  extends through a portion of the cylinder block  201  and the second cylinder head  268 . The oil passage  262  is in fluidic communication with an inlet  264  of a first oil gallery passage  266  in the second cylinder head  268 . Additionally, the oil passage  262  is in fluidic communication with an inlet  270  of a second oil gallery passage  272  included in the second cylinder head  268 . The first and second oil gallery passages ( 266  and  272 ) included in the second cylinder head  268  are in fluidic communication with a plurality of moveable engine components  274 . The moveable engine components  274  may include hydraulically operated devices. Specifically, the moveable engine components  274  include cam phasers  276 , valve adjusters  278 , camshaft bearings  280 , and a tensioner  282 . The aforementioned moveable engine components  274  may have similar functionality to the moveable engine components  232 , described above. Additionally, camshafts in the second cylinder head  268  are schematically depicted at  283  and  285 . Each cam shaft may be configured to actuate a set of intake valves or a set of exhaust valves. 
         [0033]    The first oil gallery passage  266  includes a drainage opening  284 . Likewise, the second oil gallery passage  272  includes a second drainage opening  286 . The drainage openings ( 284  and  286 ) are positioned at an end of the corresponding oil gallery passages. The drainage openings ( 284  and  286 ) may be substantially sealed when the engine assembly  200  is assembled. However, during construction the drainage openings ( 284  and  286 ) may be unsealed and flushed when the engine assembly  200  is partially assembled. The drainage openings ( 284  and  286 ) are depicted via generic boxes in  FIG. 2 . However, the geometric characteristics of the drainage opening ( 284  and  286 ) are illustrated in greater detail in  FIG. 9 . 
         [0034]      FIG. 2  also shows a plurality of reservoir return passages  288 . The reservoir return passages  288  provide fluidic communication between enclosures in the first and second cylinder heads ( 228  and  268 ) as well as the crankcase and the oil reservoir  206 . Therefore, oil may be flowed from the moveable engine components ( 232 ,  256 , and  274 ) back to the oil reservoir via the reservoir return passages  288 . In this way, oil may be delivered to various components in the engine for lubrication and then returned to the oil reservoir, thereby forming a lubrication circuit. Furthermore, oil may be flowed from the drainage openings ( 229 ,  246 ,  247 ,  284 , and/or  286 ) back to the oil reservoir via the reservoir return passages  288  when the drainage openings are unsealed. The drainage opening may be unsealed during engine manufacturing. A technique for flushing the lubrication system is discussed in greater detail herein with regard to  FIG. 11 . 
         [0035]    The oil reservoir  206 , pick-up line  208 , pump  214 , oil filter  216 , oil filter supply component  218 , oil passages ( 230 ,  262 ), the supply oil passage  220 , the valley oil gallery passage  222 , the first and second oil gallery passages ( 224  and  226 , respectively) included in the first cylinder head  228 , the first and second oil gallery passages ( 264  and  270 , respectively) included in the second cylinder head  268 , the moveable engine components( 232 ,  256 , and  274 ), and/or the reservoir return passages  288  may be included in the lubrication system  202 . 
         [0036]    It will be appreciated that the aforementioned oil gallery passages (e.g., the first oil gallery passage  224  included in the first cylinder head  228 , the second oil gallery passage  226  included in the first cylinder head, the valley oil gallery passage  222 , the first oil gallery passage  264  included in the second cylinder head  268 , and the second oil gallery passage  270  included in the second cylinder head) may be generally referred to as a first oil gallery passage, a second oil gallery passage, etc. 
         [0037]    In addition, the drain passages  229 ,  284 ,  286 ,  247 , and  246  provide low resistance bypass passages from so that oil may be passed through the first oil gallery passage  224 , the second oil gallery passage  226 , the valley oil gallery passage  222 , the first oil gallery passage  264 , and the second oil gallery passage  270  and to the oil reservoir  206  without flowing oil through a group comprising at least one of bearings, lifters, cam actuators, and tensioners. In addition, oil may be directed through the drain passages  229 ,  284 ,  286 ,  247 , and  246  via rotating the engine with drain stoppers positioned to allow flow through the drain passages. In this way, insufficient oil pressure is developed within the oil passages to allow for a substantial amount of oil to flow through the bearings, lifters, cam actuators, and tensioners. Thus, debris is directed away from hydraulic components and to the reservoir where it is pumped and removed through a filter. 
         [0038]    It should also be mentioned that the drainage passages may be opened before combustion is initiated in the engine for a first time. Opening the drainage passages before combustion allows debris to be purged from engine oil passages before the engine is operated for the first time since being manufactured. Once the debris is purged from the oil passages, oil may be directed to engine components that move so that the components are lubricated when combustion commences in the engine for the first time. 
         [0039]      FIG. 3  shows an isometric view of an example of the engine assembly  200  in the engine  10 , the engine assembly  200  includes the cylinder block  201 , the first cylinder head  228 , and the second cylinder head  268 , shown in  FIG. 2 . As shown, the assembly  200  includes the first cylinder head  228  and the second cylinder head  268 . A valley  300  is positioned between the cylinder heads. 
         [0040]    The cylinder block  201  and the first and second cylinder heads ( 228  and  268 ) both include a front side  302  including a front engine cover engaging surface  304  configured to attach to a front engine cover. Attachment openings  306  are included in the front engine cover engaging surface  304 . The attachment opening  306  may be configured to receive bolts or other suitable attachment apparatuses for attaching the front cover of the engine to the front engine cover engaging surface  304 . However, it will be appreciated that other suitable attachment techniques may be used to attach the engine front cover to the front engine cover engaging surface  304 . The cutting planes defining the cross-section shown in  FIGS. 5-10  are illustrated in  FIG. 3 . 
         [0041]      FIG. 4  shows another view of the engine assembly  200  including the cylinder block  201  and the first and second cylinder heads ( 228  and  268 ) shown in  FIG. 3 . Specifically,  FIG. 4  shows a rear side  400  of the engine assembly  200 . The rear side  400  includes a transmission bell housing engaging surface  402 . The transmission bell housing engaging surface  402  is configured to attach to a transmission bell housing. The transmission bell housing engaging surface  402  includes openings  404  configured to accept bolts or other suitable attachment apparatuses, to attach the transmission bell housing engaging surface  402  to the transmission bell housing. However, it will be appreciated that in other examples other suitable attachment techniques may be utilized. 
         [0042]      FIG. 5  shows a cross-sectional view of the engine assembly  200  shown in  FIGS. 3 and 4 . The supply oil passage  220  includes an outlet in fluidic communication with the valley oil gallery passage  222  shown in  FIG. 2 . The supply oil passage extends through a portion of the cylinder block  201 . As previously discussed, the oil passage  230  branches off the supply oil passage  220  and is in fluidic communication with the inlet  242  of the first oil gallery passage  224  included in the first cylinder head  228 . The oil passage  230  extends through a portion of the cylinder block  201  and the first cylinder head  228 . The oil passage  220  is also in fluidic communication with the inlet  248  of the second oil gallery passage  226  included in the first cylinder head  228 . Furthermore, the oil passage  220  is also in fluidic communication with inlet  254  of the valley oil gallery passage  222 . 
         [0043]      FIG. 6  shows another cross-sectional view of the engine assembly  200  shown in  FIG. 4 . The valley oil gallery passage  222  is depicted. The valley oil gallery passage  222  extends longitudinally through the engine assembly  200 . The valley oil gallery passage  222  is straight in the depicted example. However, in other examples, the valley oil gallery passage  222  may have another suitable geometric configuration. Furthermore, the valley oil gallery passage  222  extends longitudinally through the engine assembly  200  and is positioned below the valley  300 . Specifically, the valley oil gallery passage  222  longitudinally traverses the engine assembly  200  from a first peripheral cylinder  1000  included in the second cylinder head  268  to a second peripheral cylinder  1002  included in second cylinder head  268 , the first and second peripheral cylinders shown in  FIG. 10 . Additionally, the valley oil gallery passage  222  extends from the front side  302  of the engine assembly  202  to the rear side  400  of the engine assembly  200 . 
         [0044]    As shown, the valley oil gallery passage includes the inlet  254  in fluidic communication with the supply oil passage  220  shown in  FIG. 5 . Branch passages  600  are depicted. The branch passages  600  extend through bearing caps  602  include in the cylinder block  201 . It will be appreciated that the branch passages  600  may be configured to supply oil to crankshaft bearings included in a crankshaft assembly. Openings  604  may be in fluidic communication with the piston jets  258 , shown in  FIG. 2 . The valley oil gallery passage  222  includes an end  606  sealed via a stopper  608  (e.g., plug). 
         [0045]    The drainage opening  229  is also depicted in  FIG. 6 . The drainage opening is in fluidic communication with drainage passage  609  traversing the cylinder block  201 . As shown, the drainage opening  229  extends into a wall  610  of the valley oil gallery passage  222 . Furthermore, the drainage passage  609  extends in a vertical and longitudinal direction in the cylinder block  201 . A drainage opening stopper  612  is positioned in the drainage passage  609  sealing the drainage opening  229  and the drainage passage  609 . In the depicted example, the drainage opening stopper  612  is a bolt. However, in other examples other suitable drainage opening stoppers may be used. It will be appreciated that during the construction the engine assembly  200 , the drainage opening stopper  612  may not be positioned in the drainage passage  609 . When the engine assembly  202  is in such a configuration, oil may be flowed through the valley oil gallery passage  222  and out of the drainage opening  229  and drainage passage  609 . In this way, the drainage opening stopper  612  is moveable. Furthermore, the drainage opening stopper  612  extends outside of an exterior engine block wall  613  in the depicted example. Therefore, a position of the drainage opening stopper  612  may be adjustable from outside of the engine block  201 . However, other configurations are possible in other examples. It will be appreciated, that the oil flows to the oil reservoir  206 , shown in  FIG. 2 , after flowing out of the drainage passage  609 . In this way, oil may be flushed from the lubrication system  202 , shown in  FIG. 2 , prior to complete assembly of the engine assembly  200 . Furthermore, the size of the drainage opening  229  may be larger than the size of the inlets of the branch passages  602  or the size of the openings  604 . In this way, oil may flow through the drainage opening  229  when the lubrication system is being flushed, as opposed to the branch passages  602  and/or openings  604 . 
         [0046]      FIG. 7  shows another cross-sectional view of the assembly shown in  FIG. 4 . The first and second oil gallery passages ( 224  and  226 ), included in the first cylinder head  228 , are depicted. Outlets  700  are in fluidic communication with the first oil gallery passage  224  and the second oil gallery passage  226  to the moveable engine components  232 , shown in  FIG. 2 , are depicted. In this way, oil may be transferred from the first and second oil gallery passages ( 224  and  226 ) in the first cylinder head  228  to the moveable engine components  232 , depicted in  FIG. 2 . As shown, the first and second oil gallery passages ( 224  and  226 ) in the first cylinder head  228  extend longitudinally through the first cylinder head  228  and therefore the engine. Specifically, the first and second oil gallery passages ( 224  and  226 ) traverse the first cylinder head  228  from the front side  302  to the rear side  400 . In this way, oil may be supplied to a large number of moveable engine components, such as hydraulically operated devices, in the engine. Moreover, the first and second oil gallery passages ( 224  and  226 ) are shown in a straight line. However, in other examples other passage alignments and geometric configurations are possible. The drainage opening  246  in the firstly oil gallery passage  224  and the drainage opening  247  in the second oil gallery passage are shown in  FIG. 7 . The drainage opening  246  radially extends into a wall  705  of the first oil gallery passage  224 . Likewise, the drainage opening  247  radially extends into a wall  707  of the second oil gallery passage  226 . However, in other examples other orientations are possible. Furthermore, the size of the drainage openings ( 246  and  247 ) may be greater than the size of the outlets  700 . 
         [0047]    The first oil gallery passage  224  includes an end  702  and the second oil gallery passage  226  includes an end  704 . A drainage opening stopper  706  is positioned within the end  702  of the first oil gallery passage  224 . Likewise, a drainage opening stopper  708  is positioned with the end  704  of the second oil gallery passage  226 . The drainage opening stoppers ( 706  and  708 ) may both be configured to seal the ends of their respectively oil gallery passage as well as seal the drainage openings. In the depicted example, drainage opening stoppers ( 706  and  708 ) are bolts. However, in other examples other suitable stoppers may be utilized. It will be appreciated that when the drainage opening stoppers ( 706  and  708 ) are removed from the first and second oil gallery passages ( 224  and  226 ) oil may drain from the passages to the oil reservoir  206  shown in  FIG. 2 . Additionally, the drainage opening stoppers ( 706  and  708 ) extend outside an exterior cylinder head wall  709 . Therefore, the positions of the drainage opening stoppers ( 706  and  708 ) may be adjustable from outside of the first cylinder head  228 . However, in other examples other configurations are possible. 
         [0048]      FIG. 8  shows another cross-sectional view of the assembly shown in  FIG. 3 .  FIG. 8  depicts the oil passage  262  shown in  FIG. 2 . As shown, the oil passage  262  traverses the cylinder block  201  and the second cylinder head  268  and is in fluidic communication with the valley oil gallery passage  222 . The oil passage  262  is in fluidic communication with the inlet  264  of the first oil gallery passage  266  included in the second cylinder head  268 . Additionally, the oil passage  262  is in fluidic communication with the inlet  270  of the second oil gallery passage  272  included in the second cylinder head  268 . In this way, oil may flow into oil gallery passages included in the second cylinder head  268 . 
         [0049]      FIG. 9  shows another cross-sectional view of the assembly shown in  FIG. 4 . The first and second oil gallery passages ( 266  and  272 ) included in the second cylinder head  268  are depicted. As shown, the first and second oil gallery passages ( 266  and  272 ) longitudinally extend down the second cylinder head  268 . Specifically, the first and second oil gallery passages ( 266  and  272 ) extend from a front side  302  of the engine assembly  200  to a rear side  400  of the engine assembly. The drainage opening  284  as well as the drainage opening  286  are depicted. As shown, the drainage opening  284  extends through a wall  900  of the first oil gallery passage  266 . Likewise, the drainage opening  286  extends through a wall  902  of the second oil gallery passage  272 . The drainage opening  284  is positioned adjacent to an end  904  of the first oil gallery passage  266 . Likewise, the drainage opening  286  is positioned adjacent to an end  906  of the second oil gallery passage  272 . As shown, the drainage opening  284  radially extends into the first oil gallery passage  266 . Likewise, the drainage opening  286  radially extends into the second oil gallery passage  272 . However, in other examples other orientations are possible. A drainage opening stopper  908  is positioned in the end  904  of the first oil gallery passage  266 . The drainage opening stopper  908  is a bolt in the depicted example. However, other types of drainage opening stoppers have been contemplated. The drainage opening stopper  908  seals the end of the first oil gallery passage  266  as well as the drainage opening  284 , in the depicted assembled configuration. Specifically, the drainage opening stopper  908  extends across the drainage opening  284  to seal the opening. Another drainage opening stopper  910  is positioned in the second oil gallery passage  272 . The drainage opening stopper  910  seals the end of the second oil gallery passage  272  and the drainage opening  286 . The drainage opening stoppers ( 908  and  910 ) may be removed from the engine assembly  200  to unseal the drainage openings ( 284  and  286 ). Subsequently, oil may be flowed through the first and second oil gallery passages ( 266  and  272 ) and out of the drainage openings ( 284  and  286 ) to flush the lubrication system  202 , shown in  FIG. 2 . Additionally, the drainage opening stoppers ( 908  and  910 ) extend outside an exterior cylinder head wall  911 . Therefore, the positions of the drainage opening stoppers ( 908  and  910 ) may be adjustable from outside of the second cylinder head  268 . However, in other examples other configurations are possible. 
         [0050]    The first and second oil gallery passages ( 266  and  272 ) further include outlets  912 . The outlets  912  may be in fluidic communication with the moveable engine components  274 , shown in  FIG. 2 . In this way, oil may be supplied to the moveable engine components  274 , shown in  FIG. 2 . The size of the drainage openings ( 284  and  286 ) may be greater than the outlets  912 . In this way, oil may flow through the drainage openings ( 284  and  286 ) when the drainage openings are unsealed and the lubrication system is being flushed. 
         [0051]      FIG. 10  shows another cross-sectional view of the engine assembly  200  shown in  FIG. 3 . The engine assembly  200  includes a first peripheral cylinder  1000  and a second peripheral cylinder  1002  included in the second cylinder head  262  and the cylinder block  201 . It will be appreciated that the engine assembly may include additional peripheral cylinders in the first cylinder head  228  and the cylinder block  201 . Intermediary cylinders  1004  are also depicted. In the depicted embodiment, four cylinders are shown, which are half of the engine&#39;s cylinders. However, in other examples the engine assembly  200  may include an alternate number of cylinders. Additionally, the first oil gallery passage  266  is also depicted. 
         [0052]    Thus, the engine illustrated in  FIGS. 1-10  provides for an engine lubrication system comprising an engine block including an oil gallery passage extending through the engine block and supplying oil to a group of one or more moveable engine components, the oil gallery passage supplied oil from an oil pump, the oil gallery passage in fluidic communication with a drainage passage, and a movable stopper positioned in the drainage passage that selectively bypasses oil from the oil pump to an oil reservoir. The stopper and drainage passages may be threaded or may include another stopper retaining means. 
         [0053]    The engine illustrated in  FIGS. 1-10  further provides for an engine lubrication system where the drainage passage bypasses oil flow past the group of one or more moveable engine components to the oil reservoir. 
         [0054]    The engine illustrated in  FIGS. 1-10  further provides for an engine lubrication system where the moveable stopper bypasses around the group of one or more moveable engine components in a first position, and where the moveable stopper stops oil flow through the drain passage and directs oil to the group of one or more moveable engine components in a second position. 
         [0055]    The engine illustrated in  FIGS. 1-10  further provides for an engine lubrication system where the group of one or more engine components includes a hydraulically operated device, and where the hydraulically operated device is positioned upstream of the drainage passage. The engine illustrated in  FIGS. 1-10  further provides for an engine lubrication system where a position of the movable stopper is adjustable from outside of the engine block. The engine illustrated in  FIGS. 1-10  further provides for an engine lubrication system where the oil gallery passage is in fluidic communication with one or more cylinder heads. 
         [0056]    The engine illustrated in  FIGS. 1-10  further provides for an engine lubrication system further comprising an oil filter positioned downstream of the oil pump and the oil reservoir. The engine illustrated in  FIGS. 1-10  further provides for an engine lubrication system where the oil filter is positioned upstream of the oil gallery passage. 
         [0057]    The engine illustrated in  FIGS. 1-10  also provides for an engine lubrication system comprising an engine block including a first oil drainage passage in fluidic communication with a first oil gallery, a first stopper positioned in the first oil drainage passage extending outside of an exterior engine block wall, a cylinder head coupled to the engine block and including a second oil drainage passage, and a second stopper positioned in the second oil drainage passage extending outside an exterior cylinder head wall. The engine illustrated in  FIGS. 1-10  further provides for an engine lubrication system further comprising a second oil gallery within the cylinder head and in fluidic communication with the second oil drainage passage and the first oil gallery, the second oil gallery positioned between the second oil drainage passage and the first oil gallery. 
         [0058]    The engine illustrated in  FIGS. 1-10  further provides for an engine lubrication system further comprising a third oil gallery within the cylinder head and in fluidic communication with the second oil gallery and the first oil gallery, the second oil drainage passage directing oil to an oil reservoir. The engine illustrated in  FIGS. 1-10  further provides for an engine lubrication system further comprising a third drainage passage in fluidic communication with the third oil gallery, the third drainage passage directing oil to the oil reservoir. 
         [0059]    The engine illustrated in  FIGS. 1-10  further provides for an engine lubrication system where the first stopper allows oil to bypass a hydraulically operated device and flow to an oil reservoir when in a first position, and where the first stopper prevents oil from bypassing the hydraulically operated device and seals the oil drainage passage when in a second position. The engine illustrated in  FIGS. 1-10  further provides for an engine lubrication system further comprising an oil filter coupled to the engine block and filtering oil provided to the first oil gallery. 
         [0060]      FIG. 11  shows a method  1100  for operation of a lubrication system in an engine assembly. The engine assembly described above with regard to  FIGS. 1-9  may be used to implement method  1100  or another suitable engine may be used to implement method  1100 . 
         [0061]    At  1102 , the method includes pumping oil from a reservoir to a cylinder block oil gallery. At  1104  the method further includes opening a drainage passage from the cylinder block oil gallery to the reservoir. 
         [0062]    Next at  1106  the method includes closing the drainage passage and stopping oil flow through the drainage passage to the reservoir while the engine is combusting an air-fuel mixture. In some examples, the engine is not combusting an air-fuel mixture when the drainage passage is open. Further in some examples, the drainage passage is closed via a stopper. 
         [0063]    At  1108  the method includes pumping oil from the reservoir to a cylinder head oil gallery and at  1110  the method includes opening a drainage passage from the cylinder head oil gallery to the reservoir. At  1112  the method includes closing the drainage passage from the cylinder head oil gallery to the reservoir. Next at  1114  the method includes stopping oil flow through the drainage passage from the cylinder head oil gallery to the reservoir while the engine is combusting an air-fuel mixture. In some examples, the cylinder block oil gallery supplies oil to one or more pistons. 
         [0064]    Method  1100  enables the oil gallery passage to be flushed of any unwanted particulates prior to full assembly of the engine assembly. In this way, the likelihood of unwanted particulates in the oil flowing through the hydraulic devices is reduced. As a result, the longevity of the engine assembly is increased. 
         [0065]    The method shown in  FIG. 11  provides for a method for operating a lubrication system of an engine, comprising pumping oil from a reservoir to a cylinder block oil gallery, opening a drainage passage from the cylinder block oil gallery to the reservoir, and closing the drainage passage and stopping oil flow through the drainage passage to the reservoir while the engine is combusting an air-fuel mixture. The method shown in  FIG. 11  further provides for a method where the engine is not combusting an air-fuel mixture when the drainage passage is open and/or where the drainage passage is closed via a stopper. 
         [0066]    The method shown in  FIG. 11  also provided for a method further comprising pumping oil from the reservoir to a cylinder head oil gallery and opening a drainage passage from the cylinder head oil gallery to the reservoir. The method shown in  FIG. 11  also provided for a method further comprising closing the drainage passage from the cylinder head oil gallery to the reservoir and stopping oil flow through the drainage passage from the cylinder head oil gallery to the reservoir while the engine is combusting an air-fuel mixture. The method shown in  FIG. 11  further provides for a method where the cylinder block oil gallery supplies oil to one or more pistons. 
         [0067]    As will be appreciated by one of ordinary skill in the art, the method described in  FIG. 11  may represent one or more of any number of processing strategies such as event-driven, interrupt-driven, multi-tasking, multi-threading, and the like. As such, various steps or functions illustrated may be performed in the sequence illustrated, in parallel, or in some cases omitted. Likewise, the order of processing is not necessarily required to achieve the objects, features, and advantages described herein, but is provided for ease of illustration and description. Although not explicitly illustrated, one of ordinary skill in the art will recognize that one or more of the illustrated steps or functions may be repeatedly performed depending on the particular strategy being used. 
         [0068]    This concludes the description. The reading of it by those skilled in the art would bring to mind many alterations and modifications without departing from the spirit and the scope of the description. For example, single cylinder, I2, I3, I4, I5, V6, V8, V10, V12 and V16 engines operating in natural gas, gasoline, diesel, or alternative fuel configurations could use the present description to advantage.