Apparatus and method for controlling the operation of a cooling system for a marine propulsion device
View Patent ↗A cooling system for a marine propulsion device provides a bypass loop around a cooling pump that allows the flow of cooling water through certain components to be reduced or increased as a function of the temperature of those components while causing a full flow of cooling water to flow through other selected heat emitting devices. Using this configuration of components and bypass conduits, the operating condition of the cooling water pump can be continually monitored, including the condition of its flexible vanes. By observing the effective cooling capacity of the system under conditions with the bypass valve open and closed, the effectiveness of the cooling water pump can be assessed and a suggestion of maintenance can be provided.
1. A method for controlling a cooling system for a marine propulsion device, comprising the steps of:
disposing a cooling passage in thermal communication with a heat emitting component;
providing an inlet conduit and an outlet conduit, said inlet conduit being configured to conduct water to a pump from a body of water in which said marine propulsion device is operated, said outlet conduit being connected in fluid communication with said cooling passage;
providing the pump having an outlet port connected in fluid communication with said outlet conduit and an inlet port connected in fluid communication with said inlet conduit;
connecting a bypass conduit in fluid communication between said outlet conduit and said inlet conduit;
connecting a valve in fluid communication with said bypass conduit, said valve being configured to affect the rate of flow of water from said outlet conduit to said inlet conduit;
measuring a representative temperature of said cooling system;
determining a preferred state of said valve as a function of said representative temperature; and
causing said valve to be in said preferred state.
2. The method of claim 1 , wherein:
said determining step comprises the steps of selecting a closed state as said preferred state when said representative temperature is above a preselected upper threshold magnitude and selecting an open state as said preferred state when said representative temperature is below a preselected lower threshold magnitude.
3. The method of claim 2 , further comprising:
monitoring the elapsed time for said representative temperature to achieve said lower threshold magnitude after said valve is caused to change from said open state to said closed state and assessing the operating condition of said pump as a function of said elapsed time.
4. The method of claim 2 , further comprising:
monitoring the elapsed time that said valve is in said closed state before said representative temperature is generally equal to said lower threshold magnitude and assessing the operating condition of said pump as a function of said elapsed time.
5. The method of claim 2 , further comprising:
monitoring the response of said representative temperature as a function of said state of said valve and assessing the operating condition of said pump as a function of said response.
6. The method of claim 1 , wherein:
said measuring step comprises the steps of measuring a first temperature at a first preselected location of said marine propulsion device and of measuring a second temperature at a second preselected location of said marine propulsion device.
7. The method of claim 6 , wherein:
said first preselected location is at an exhaust conduit and said second preselected location is within a flow of coolant.
8. The method of claim 6 , wherein:
said representative temperature is a function of the higher of said first and second temperatures.
9. The method of claim 1 , wherein:
said heat emitting component is a heat exchanger having a coolant circuit disposed in thermal communication with said cooling passage; and
said measuring step comprises the step of measuring a temperature of coolant flowing through said coolant circuit.
10. The method of claim 1 , further comprising:
connecting a fuel cooler in fluid communication with said outlet conduit between said pump and said valve;
connecting a steering fluid cooler in fluid communication with said outlet conduit between said pump and said valve;
connecting an oil cooler in fluid communication with said outlet conduit, said bypass conduit being connected to said outlet conduit between said pump and said oil cooler; and
connecting an exhaust conduit in fluid communication with said outlet conduit, said bypass conduit being connected to said outlet conduit between said pump and said exhaust conduit.
11. A method for controlling a cooling system for a marine propulsion device, comprising the steps of:
disposing a cooling passage in thermal communication with a heat emitting component;
providing an inlet conduit and an outlet conduit, said inlet conduit being configured to conduct water to a pump from a body of water in which said marine propulsion device is operated, said outlet conduit being connected in fluid communication with said cooling passage;
providing the pump having an outlet port connected in fluid communication with said outlet conduit and an inlet port connected in fluid communication with said inlet conduit;
connecting a bypass conduit in fluid communication between said outlet conduit and said inlet conduit;
connecting a valve in fluid communication with said bypass conduit, said valve being configured to affect the rate of flow of water from said outlet conduit to said inlet conduit;
measuring a representative temperature of said cooling system;
determining a preferred state of said valve as a function of said representative temperature, said determining step comprising the steps of selecting a closed state as said preferred state when said representative temperature is above a preselected upper threshold magnitude and selecting an open state as said preferred state when said representative temperature is below a preselected lower threshold magnitude;
causing said valve to be in said preferred state;
monitoring the response of said representative temperature as a function of said state of said valve; and
assessing the operating condition of said pump as a function of said response.
12. The method of claim 11 , wherein:
said monitoring step comprises the step of measuring the elapsed time for said representative temperature to achieve said lower threshold magnitude after said valve is caused to change from said open state to said closed state.
13. The method of claim 11 , further comprising:
said monitoring step comprises the step of measuring the elapsed time that said valve is in said closed state before said representative temperature is generally equal to said lower threshold magnitude.
14. The method of claim 11 , wherein:
said measuring step comprises the steps of measuring a first temperature at a first preselected location of said marine propulsion device and of measuring a second temperature at a second preselected location of said marine propulsion device.
15. The method of claim 14 , wherein:
said representative temperature is a function of the higher of said first and second temperatures.
16. The method of claim 15 , wherein:
said heat emitting component is a heat exchanger having a coolant circuit disposed in thermal communication with said cooling passage; and
said measuring step comprises the step of measuring a temperature of coolant flowing through said coolant circuit.
17. The method of claim 16 , further comprising:
connecting a fuel cooler in fluid communication with said outlet conduit between said pump and said valve;
connecting a steering fluid cooler in fluid communication with said outlet conduit between said pump and said valve;
connecting an oil cooler in fluid communication with said outlet conduit, said bypass conduit being connected to said outlet conduit between said pump and said oil cooler; and
connecting an exhaust conduit in fluid communication with said outlet conduit, said bypass conduit being connected to said outlet conduit between said pump and said exhaust conduit.
18. A method for controlling a cooling system for a marine propulsion device, comprising the steps of:
disposing a cooling passage in thermal communication with a heat emitting component;
providing an inlet conduit and an outlet conduit, said inlet conduit being configured to conduct water to a pump from a body of water in which said marine propulsion device is operated, said outlet conduit being connected in fluid communication with said cooling passage;
providing the pump having an outlet port connected in fluid communication with said outlet conduit and an inlet port connected in fluid communication with said inlet conduit;
connecting a bypass conduit in fluid communication between said outlet conduit and said inlet conduit;
connecting a valve in fluid communication with said bypass conduit, said valve being configured to affect the rate of flow of water from said outlet conduit to said inlet conduit;
measuring a representative temperature of said cooling system;
determining a preferred state of said valve as a function of said representative temperature, said determining step comprising the steps of selecting a closed state as said preferred state when said representative temperature is above a preselected upper threshold magnitude and selecting an open state as said preferred state when said representative temperature is below a preselected lower threshold magnitude;
causing said valve to be in said preferred state;
monitoring the response of said representative temperature as a function of said state of said valve; and
assessing the operating condition of said pump as a function of said response.
19. The method of claim 18 , wherein:
said monitoring step is selected from the group consisting of the steps of measuring the elapsed time for said representative temperature to achieve said lower threshold magnitude after said valve is caused to change from said open state to said closed state and measuring the elapsed time that said valve is in said closed state before said representative temperature is generally equal to said lower threshold magnitude.
20. The method of claim 18 , wherein:
said measuring step comprises the steps of measuring a first temperature at a first preselected location of said marine propulsion device and of measuring a second temperature at a second preselected location of said marine propulsion device,
said heat emitting component being a heat exchanger having a coolant circuit disposed in thermal communication with said cooling passage and
said measuring step comprising the step of measuring a temperature of coolant flowing through said coolant circuit.