I have been doing a lot of reading here in an effort to troubleshoot my 1994 Johnson 40 hp.
If it helps, the number is J 40 T L ER E.
Some history on the motor.....The prior owner had the oil injection disabled and has mixed the gas for years. Prior owner had a problem with the motor running terrible at WOT. He took it to the dealership and they changed the power pack and he parked the boat. The next time out (the following season) the boat experienced the same problem.
I have satisfied myself that the fuel system is ok. I believe the the problem is related to a sensor that is activating a safety system in an effort to protect the engine. When I first start the motor at the dock, all is well. Within a minute or so of getting under way the alarm will start dinging in the shifter. If I open the motor to WOT it will run great for about a minute and then start surging and sputtering. Backing the throttle off will let the boat run good. The alarm dings repeatedly regardless of throttle position.
I would like to try disconnecting the wire(s) to the VRO in case that is what is triggering the alarm. The problem is that I know nothing about these motors and dont even know if this would work.
My second guess is maybe the temp sensor is bad or the thermostat is bad. The tattle tale hose on the rear of the motor appears to be pumping great with a real good stream coming out of it. Is it possible to disconnect the temp sensor to silence the alarm? I am only wanting to do this as a trouble shooting method as I cant afford to just throw parts money at the motor until I find the problem. If I can silence the alarm, that will help narrow down which parts to try.
My problem is that I dont know where to try disconnecting the wires to test the motor. If my ideas sound correct, can someone post some pictures or detailed explanations on where I can disconnect the wires? Please keep in mind that I am not knowledgeable on this motor so any explanations need to be real stupid proof. Thanks for the help.
If it helps, the number is J 40 T L ER E.
Some history on the motor.....The prior owner had the oil injection disabled and has mixed the gas for years. Prior owner had a problem with the motor running terrible at WOT. He took it to the dealership and they changed the power pack and he parked the boat. The next time out (the following season) the boat experienced the same problem.
I have satisfied myself that the fuel system is ok. I believe the the problem is related to a sensor that is activating a safety system in an effort to protect the engine. When I first start the motor at the dock, all is well. Within a minute or so of getting under way the alarm will start dinging in the shifter. If I open the motor to WOT it will run great for about a minute and then start surging and sputtering. Backing the throttle off will let the boat run good. The alarm dings repeatedly regardless of throttle position.
I would like to try disconnecting the wire(s) to the VRO in case that is what is triggering the alarm. The problem is that I know nothing about these motors and dont even know if this would work.
My second guess is maybe the temp sensor is bad or the thermostat is bad. The tattle tale hose on the rear of the motor appears to be pumping great with a real good stream coming out of it. Is it possible to disconnect the temp sensor to silence the alarm? I am only wanting to do this as a trouble shooting method as I cant afford to just throw parts money at the motor until I find the problem. If I can silence the alarm, that will help narrow down which parts to try.
My problem is that I dont know where to try disconnecting the wires to test the motor. If my ideas sound correct, can someone post some pictures or detailed explanations on where I can disconnect the wires? Please keep in mind that I am not knowledgeable on this motor so any explanations need to be real stupid proof. Thanks for the help.
