Engine oil leak test system and method

Abstract

A system and method for testing partially assembled engines for possible oil leaks. The system includes engine pressurizing devices that are automatically controlled by a controller according to a predetermined control program based upon the engine model type being tested. The pressurizing devices introduce pressurized air into the engine oil system. A leak testing unit monitors the pressurized engine for pressure drops indicative of an oil seal leak. Air pressure leaks resulting from inherently air-porous EGR valves are compensated for by an EGR compensating unit, which provides pressurized air to an intake side of the EGR valve. The flow of pressurized air through the EGR compensating unit is monitored to determine whether there is a problem with the EGR valve.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

These and further features of the invention will be apparent with reference to the following description and drawings, wherein:

FIG. 1 is a schematic front view of an engine and a pressurizing apparatus;

FIG. 2 is a schematic top plan view of the engine and portions of the pressurizing apparatus;

FIG. 3 is a schematic side view of the engine and portions of the pressurizing apparatus;

FIG. 4 is a schematic illustration of a control system for the leak testing station;

FIG. 5 is a schematic illustration of pneumatic connections for the leak testing station;

FIG. 6 schematically illustrates a leak testing station and engine prior to a leak testing procedure;

FIG. 7 schematically illustrates a similar leak testing station and engine during a leak testing procedure

FIG. 8 schematically illustrates a leak testing station as in FIG. 7, but with an adaptor for accommodating an engine with an exhaust manifold outlet secured thereto; and,

FIG. 9 is a flowchart showing steps of a leak testing method according to the present invention.

Claims

1. An engine oil leak testing station for testing an engine for possible oil leaks, said engine comprising an air intake base, an exhaust manifold, and exhaust gas recirculation (EGR) valve, and head covers including an oil fill tube and at least one port, said testing station comprising: a controller that is operable to initiate a testing sequence;sealing head units for, upon initiation of said testing sequence, sealing against associated portions of said engine and introducing pressurized air into said engine via one or more of said engine air intake base, exhaust manifold, oil fill tube and port;a leak testing unit that is operable to sense changes in pressure within said engine.

2. The testing station of claim 1, further comprising an EGR compensating unit that is operable to provide a flow of pressurized air to an intake side of said EGR valve so as to compensate for air leaking from said EGR valve.

3. The testing station of claim 2, further comprising actuators associated with at least some of said sealing head units and operable, under the control of the controller, to move said at least some sealing head units into and out of sealing engagement with said associated engine portions.

4. The testing station of claim 3, further comprising at least one robot associated with at least one of said sealing head units and operable, under the control of the controller, to move said at least one sealing head unit into and out of sealing engagement with said associated engine portion.

5. The testing station of claim 1, further comprising a quick charge valve that is operable to introduce pressurized air into said engine via one or more of said engine air intake base, exhaust manifold, oil fill tube and port.

6. The testing station of claim 5, further comprising an EGR compensating unit that is operable to provide a flow of pressurized air to an intake side of said EGR valve so as to compensate for air leaking from said EGR valve.

7. The testing station of claim 6, further comprising actuators associated with at least some of said sealing head units and operable, under the control of the controller, to move said at least some sealing head units into and out of sealing engagement with said associated engine portions.

8. The testing station of claim 7, further comprising at least one robot associated with at least one of said sealing head units and operable, under the control of the controller, to move said at least one sealing head unit into and out of sealing engagement with said associated engine portion.

9. The testing station of claim 1, wherein said controller initiates a predetermined control program based upon a model type of said engine, and wherein said engine model type is automatically provided to said controller.

10. The testing station of claim 9, further comprising a means for sensing a model type of said engine, said controller using said engine model type to select a predetermined control program designed for said engine model type from a plurality of predetermined programs.

11. The testing station of claim 1, wherein said sealing head units introduce pressurized air via each of said engine air intake base, exhaust manifold, oil fill tube and port.

12. The testing station of claim 11, further comprising an EGR compensating unit and a quick charge valve, said EGR compensating unit being is operable to provide a flow of pressurized air to an intake side of said EGR valve so as to compensate for air leaking from said EGR valve, said quick charge valve being operable to introduce pressurized air into said engine via each of said engine air intake base, exhaust manifold, oil fill tube and port.

13. The testing station of claim 12, further comprising actuators associated with at least some of said sealing head units and operable, under the control of the controller, to move said at least some sealing head units into and out of sealing engagement with said associated engine portions.

14. The testing station of claim 13, further comprising at least one robot associated with at least one of said sealing head units and operable, under the control of the controller, to move said at least one sealing head unit into and out of sealing engagement with said associated engine portion.

15. A method for testing an engine for possible oil leaks, said engine comprising an air intake base, an exhaust manifold, and exhaust gas recirculation (EGR) valve, and head covers including an oil fill tube and at least one port, said method comprising the steps of: selecting one control program from a plurality of control programs based upon a model type of the engine being tested;initiating the selected control program;sealingly connecting a seal head unit to each of said air intake base, exhaust manifold, oil fill tube, and port;pressurizing said engine by introducing pressurized air through at least one of said air intake base, exhaust manifold, oil fill tube, and port;after said engine is pressurized, monitoring said engine pressure for a predetermined period of time to detect a drop in engine pressure; and,using the detected drop in engine pressure to determine whether said engine may have a possible oil leak.

16. The method according to claim 15, further comprising the steps of: supplying pressurized air to an intake side of said EGR valve to compensate for air leaks in said EGR valve.

17. The method according to claim 16, comprising the further steps of: while monitoring the engine pressure, measuring a flow rate of pressurized air to said EGR valve intake side; and, using said measured flow rate to determine whether the EGR valve is functioning properly.

18. The method according to claim 15, wherein said selecting step includes the step of: determining the model type of said engine.

19. The method according to claim 18, wherein a model type is stored on a data storage device proximal to said engine, and wherein said engine model type is determined by accessing engine model type data from said data storage device.