Patent Abstract:
A fuel system pressure tester for motorcycles adapted to be connected in-line with a fuel tank female fitting and a fuel line male fitting, has a fitting body, a first fitting for connection with the fuel tank fitting with an internal, normally closed valve, a second fitting for connection with the fuel line fitting, a pressure gauge, and a manually operated valve with a valve actuating element and a connection for a fuel hose. The fitting body has an internal passageway connecting the first fitting, the second fitting, the pressure gauge, and the manually operated valve. A method of testing a fuel system of the motorcycle involves connecting the pressure tester to the fuel tank by connecting the male tester fitting with the fuel tank female fitting, and connecting the female tester fitting with the fuel line male fitting, energizing the in-tank fuel sending unit, and reading pressure within the tester indicated by the pressure gauge.

Full Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the priority of Provisional Application No. 61/784,017, filed on Mar. 14, 2013, which is herewith incorporated by reference in its entirety. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to a testing device for a motor vehicle and in particular to a pressure tester for fuel systems adapted for motorcycles. 
     BACKGROUND OF THE INVENTION 
     In maintenance and diagnostic procedures, certain tests are performed for fuel systems to determine if elements of the system are operating properly. Modern large motorcycles feature a fuel sending unit disposed inside the fuel tank of the motorcycle. The sending unit typically includes an electric fuel pump along with a pickup tube, filter screen, and a fuel level sensor. The sending unit is powered by the vehicle electrical bus and pressurizes the fuel and supplies it to a fuel line, which leads to the induction system of the vehicle engine, typically a fuel injection unit, although some older motorcycles use carburetors. 
     Maintenance professionals use a variety of diagnostic tools in tracking down vehicle maintenance and breakdown issues. A fast and accurate testing system is desired, which enables the fuel pressure generated by the fuel sending unit to be measured. It is preferred that the use of such a diagnostic tool can be done quickly and with a minimal number of steps required of the maintenance technician. The tool should also be usable without causing unnecessary spillage of highly flammable gasoline in the symbol to operate. 
     In addition to a fuel system pressure test in a static or idle condition; namely, a condition in which the vehicle&#39;s engine is not demanding a maximum of fuel flow rate, there is further a need to measure fuel pressure in an operating condition which is equivalent to a full load condition. Ideally, such a fuel system test may be carried out without requiring that the engine being operated at full power, either on the road or on a chassis dynamometer. Both of these requirements are labor and equipment intensive and pose certain risks. Moreover, some fuel system faults cannot be resolved without performing a load test. For example, a clogged or partially clogged fuel pickup screen may be capable of enabling a normal no-load pressure to be generated, while such a fault would not permit pressure to be maintained in a fuel flow condition equivalent to a high-power operating condition of the engine. 
     SUMMARY OF THE INVENTION 
     The fuel system pressure tester in accordance with this invention is adapted to be quickly connected in-line with a conventional motorcycle fuel system. The system of the present invention enables tests to be carried out quickly, without special tools, and can provide both static and load testing evaluations. 
     According to one aspect of the invention, a fuel system pressure tester for motorcycles is adapted to be connected in-line with a fuel tank female fitting and a fuel line male fitting. The pressure tester includes a fitting body, a male fitting affixed to the fitting body adapted for connection with the fuel tank female fitting, a female fitting affixed to the fitting body adapted for connection with the fuel line male fitting, a pressure gauge affixed to the fitting body, a manually operated valve affixed to the fitting body having a valve actuating element and a connection for a fuel hose, and an internal passageway in the fitting body connecting the male fitting, the female fitting, the pressure gauge, and the manually operated valve. 
     According to another aspect of the invention, the valve actuating element may be a plunger element and the manually operated valve is normally in a closed condition and opens when the plunger element is actuated. 
     According to a further aspect of the invention, the female fitting has an internal normally closed valve with a valve member and a valve seat, and the fuel system pressure tester may further include a venting tool with a post having a sufficient length to remove the valve member of the female fitting from the valve seat and to open the manually operated valve. The venting tool may be attached to the fitting body with a flexible strap. 
     According to yet another aspect of the invention, a method of testing a fuel system of a motorcycle having a fuel tank with a female fitting, a fuel line with a male fitting, and an in-tank fuel sending unit, includes the steps of providing a pressure tester having a fitting body, a male tester fitting affixed to the fitting body adapted for connection with the fuel tank female fitting, a female tester fitting affixed to the fitting body adapted for connection with the fuel line male fitting, a pressure gauge affixed to the fitting body, a valve affixed to the fitting body having a valve actuating element and a connection for a fuel hose, the fitting body having an internal passageway connecting the male tester fitting, the female tester fitting, the pressure gauge, and the manually operated valve, connecting the pressure tester to the fuel tank by connecting the male tester fitting with the fuel tank female fitting, and connecting the female tester fitting with the fuel line male fitting, energizing the in-tank fuel sending unit, and reading pressure within the tester indicated by the pressure gauge. 
     According to another aspect of the invention, the method may further include the step of relieving pressure in the pressure tester after reading the pressure by activating the valve actuating element. 
     According to a further aspect of the invention, the method may further include the step of conducting a fuel pressure load test by inserting the fuel hose into a receptacle and reading the pressure step occurring while the valve actuating element is operated and causes a fuel flow through the pressure tester simulating a full-load operating condition of the motorcycle engine. The receptacle may be the fuel tank of the motorcycle, and the fuel hose may be inserted through a filler opening of the fuel tank. 
     After completion of the tests, the method may further include the steps of deenergizing the in-tank fuel sending unit, inserting the fuel hose into a receptacle, operating the valve actuating element, and releasing fuel through the fuel hose until atmospheric pressure prevails inside the fitting body. Afterwards, the pressure tester may be disconnected from the fuel tank by disconnecting the male tester fitting from the fuel tank female fitting, and by disconnecting the female tester fitting from the fuel line male fitting. A post of a venting tool may be inserted into the female fitting for opening an internal valve while the fuel hose is or remains inserted in the receptacle. Operating the valve actuating element will then allow the fuel to drain from the fitting body through the fuel hose by gravitational force. 
     Further details and benefits will become apparent by the following description of the accompanying drawings. 
    
    
     
       BRIEF SUMMARY OF THE DRAWINGS 
       In the drawings, 
         FIG. 1  shows a fuel system pressure tester in accordance with this invention; 
         FIG. 2  shows the fuel system pressure tester of  FIG. 1  coupled with a motorcycle fuel tank and fuel line and conducting a static pressure test or a load fuel system pressure test; 
         FIG. 3  shows a detail of the fuel system pressure tester of  FIG. 1  in a cross-section along the line A-A; and 
         FIGS. 4 a  and 4 b    show further alternative details of the fuel system pressure tester of  FIG. 1  in a cross-section along the image plane. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The drawing figures are included for purely illustrative purposes and are not intended to limit the scope of the invention. The drawings, in particular  FIGS. 4 a  and 4 b   , are not necessarily to scale, unless specified. 
     The fuel system pressure tester in accordance with this invention is shown in  FIGS. 1 and 2  and is generally designated by reference number  10 . Pressure tester  10  is particularly adapted for use with heavyweight Harley-Davidson motorcycles, such as model types Dyna, Softail, or Touring, to name a few, which are very numerous in the United States and around the world. Pressure tester  10  could be adapted for use with other motorcycle models and brands with provisions of suitable fuel system connections. 
     As shown in  FIG. 2 , the associated motorcycle has fuel tank  12  having an extending female quick connect fitting  14 . Fitting  14  is normally connected with fuel line  16  which has a complementary male fitting  18 . To provide ease of installation on the vehicle and servicing, fittings  14  and  18  are easily connected and disconnected. Female fuel connection fitting  14  includes an axially moving movable outer sleeve  20  which can be pushed up when it is desired to insert and connect male fitting  18  or when it is desired to release male fitting  18 . Accordingly, in the normal use condition, male fitting  18  and fuel line  16  would be connected to the fuel tank  12  through the connection formed by fittings  14  and  18 . Female fuel tank fitting  14  includes an internal plunger type valve (not shown in  FIG. 2 ), which is closed when male fitting  18  is disconnected to prevent uncontrolled fuel leakage. Connection of male fitting  18  to fitting  14  acts on the internal valve element to open the flow path when the two fittings are connected. 
     Fuel system pressure tester  10 , which is shown as a separate device in  FIG. 1  and connected to the motorcycle in  FIG. 2 , includes fitting body  22  having an internal hollow passageway communicating with the number of flow paths as will be described. Fitting body  22  forms male fitting  24 , which is identically dimensioned as is male fitting  18 , enabling male fitting  24  to be connected to fuel tank  12  in a manner equivalent to the connection with fuel line fitting  18 . Fitting body  22  further forms a female fitting  26  identical in construction with fuel tank fitting  14  also having an axially movable sleeve  28 . Male fitting  24  and female fitting  26  are shown in greater detail in  FIG. 3 . Each of the female and male fittings  26  and  24  contains a valve  50 , which is held open when the fittings  26  and  24  are coupled with the male and female connectors  18  and  20  of the motorcycle, thereby allowing fuel to flow through the fitting body  22 . When the fittings  26  and  24  are disconnected, a spring  52  in each of the valves  50  closes the valve  50  by allowing a valve member  54  to seal against an annular seat  56  formed by an O-ring, thereby stopping the flow of fuel through the fitting. 
     Fitting body  22  further features a drilled and tapped pressure gauge port  30  (not shown in detail) which receives pressure gauge  32 . Valve  34  is also a threaded into an associated threaded valve port  36  (not shown in detail) and includes an internal plunger type valve  38 , which is normally closed. Internal components of plunger valve  38  may be similar to or identical with Schrader type inflation valves found in vehicle tires. When plunger end  40  is depressed, a fuel flow path opens through valve fitting  36  and into nipple  42  having relief and gas flow hose  44  attached thereto. The internal cavity of fitting body  22  communicates with internal passageway  25  of each of fittings  24  and  26 , as well as ports  30  and  36 . 
       FIGS. 4 a  and 4 b    show two embodiments of valves  38 ′ and  38 ″ that may form manually operated valve  38 . Valve  38 ′ of  FIG. 4 a    is a spring-loaded seat valve operated by a ramp  62  that is moved by the plunger end  40  of plunger  60 ′. The plunger  60 ′ is biased outward by a spring  64  so that valve  38  is normally closed. Upon pressing plunger end  40 , the ramp  62  acts on valve member  64  against a valve spring and removes the valve member  64  from its valve seat. Seat valves have the advantage that elastic components can compensate for manufacturing tolerances so that productions costs are low. 
     While not shown, a seat valve may alternatively be arranged coaxially with the plunger  60 ′, for instance a valve similar to the one in the female fitting, where the valve member is biased toward the plunger end  40  and rests on a valve seat between the valve member and the plunger. The valve member may be arranged in the fitting body between the nipple  42  on one side and the male and female fittings on the other side. This arrangement would have the advantage that the pressure inside the fitting body  22  acts on the valve in the valve closing direction. 
       FIG. 4 b    shows a machined sliding valve  38 ″. Plunger  60 ″ has an internal channel extending from its distal axial face to a radial opening  66  that normally has no overlap with a radial bore  68  through nipple  42 . Upon pressing plunger end  40 , the radial opening  66  is aligned with the radial bore  68 , thus establishing a fluid communication of male and female fittings  24  and  26  with bore  68 . A sliding valve has the advantage that the pressure inside the fitting body  22  acts on the plunger in the valve closing direction so that the valve  38 ″ cannot be opened by a high internal pressure. 
     Use and operation of pressure tester  10  will now be described with reference to  FIG. 2 . As mentioned previously, in the normal operating condition of the motorcycle, fuel line  16  is connected with fuel tank  12  through quick connect fittings  14  and  18 . When it is desired to conduct a static, idle, or part-load pressure test, pressure tester  10  is inserted in-line with fuel line  16 , as shown in  FIG. 2 . Pressure tester  10  does not interfere with the flow of fuel from the fuel tank  12  to the associated engine, enabling it to be operated during the testing process. Some motorcycles are designed such that its electric fuel pump will not operate without the engine running as a safety feature to prevent a dangerous fuel spillage condition from occurring. When pressure tester  10  is installed as shown in  FIG. 2 , the associated motorcycle engine may be operated, for example in an idle condition. Such operation will cause the internal fuel sending unit within the tank  12  to be activated, supplying pressurized fuel through pressure tester  10  and into fuel line  16 . Pressure gauge  32  reads the pressure of the fuel within the fuel line. This can be used as a diagnostic tool to determine if the measured pressure is within predetermined limits for a partial load condition. In this operating condition, plunger valve  38  is not operated. 
     For motorcycles that allow the fuel pump to operate to provide a fuel pressure without operating the engine, a static fuel pressure test can be performed by starting the fuel pump, but not the engine, so that no fuel flow occurs through the fuel line  16 . 
     If it is only desired to conduct a static or partial load pressure test, after reading pressure from pressure gauge  32 , pressure tester  10  may be removed after shutting off the motorcycle engine. Since pressurized fuel remains within the fuel system after the sending unit is deactivated, it is desirable to provide a pressure relief feature. This is provided by plunger valve  38  and its connection with hose  44 . The distal end of hose  44  can be placed into fuel tank  12 &#39;s fuel filler opening (not shown), and the plunger end  40  may be depressed, which will squirt a small quantity of fuel into the tank. This relieves pressure in the tester  10  and the associated fuel delivery system components of the motorcycle, and enables the tester to be disconnected without a spray of fuel at the connections. 
     Pressure tester  10  may also be used to provide a fuel system load pressure test in which fuel system pressure is measured while the fuel system is delivering fuel at a high flow rate, for example, equivalent to a maximum-load, full-throttle condition of the engine, but without requiring the motorcycle engine to be operated at the full-throttle condition. This can be done by depressing plunger end  40  while the vehicle is engine is running at idle, and placing the distal end of hose  44  into the tank fuel filler opening. In this case a small flow of fuel is flowing through fuel line  16  to the engine, which is operating at an idle condition. However, a significant flow rate of fuel occurs through valve  34  and hose  44  and, therefore, the fuel system components in fuel tank  12  are delivering fuel at a high rate simulating a full-throttle, full-load operating condition. To this end, the path to and through the valve  34  may be provided with a calibrated orifice dimensioned for a fuel flow that corresponds to the difference between the fuel consumption of the idling engine and the fuel consumption of the engine run at full throttle to that the sum of the fuel flow through the fuel line  16  and through the hose  44  properly simulates the fuel flow through the fuel line  16  when the engine runs at full throttle. Instead of a calibrated orifice, the pressure tester  10  may in its entirety inherently have an overall maximum flow capacity through hose  44  that corresponds to the difference to the difference between the fuel consumption of the idling engine and the fuel consumption of the engine run at full throttle. 
     In analogy, the above-described test may be likewise performed by only operating the fuel pump with battery power without starting the engine, where possible. The fuel flow through hose  44  simulates an operating engine. The fuel consumption of an idling engine is very low compared with a full-throttle condition so that the lack of fuel flow to an idling engine may be insignificant for measuring purposes. It is, however, conceivable to provide for a variety of insertable orifices (not shown) that are dimensioned for simulating various operating conditions with or without a running engine. 
     Pressure as measured by pressure gauge  32  is recorded to determine if it meets manufacturer specifications for such operating conditions. After either the static (partial load) or a load test, the engine is stopped and pressure tensor tester  10  is disconnected after relieving any residual pressure in the system by a depressing plunger valve end  40 . 
     A venting tool with a post  46  is provided which is attached to pressure sensor  10  by a flexible strap  48 . Venting post  46  is provided to be inserted into female fitting  26  to depress its internal valve member  54  to permit drainage of fuel in tester  10  after it is disconnected from fuel tank  12 . When simultaneously the plunger end  40  is depressed, the drainage occurs by the force of gravity through hose  44 . 
     While the above description constitutes the preferred embodiment of the present invention, it will be appreciated that the invention is susceptible to modification, variation and change without departing from the proper scope and fair meaning of the accompanying claims.

Technology Classification (CPC): 6