DF-40 trys to start as soon as i connect battery

[Mechanicallychallanged]

Was out on the boat the other day and had trouble starting up the motor. Red battery cable got very hot, seems like i fried something, now when i reconnect the red the motor tries to start. I figured it was the ignition but i bought a new harness and it still tries to start when i hook up battery even with the key not in. Any help would be appreciated.

 

[montanabay]

Re: DF-40 trys to start as soon as i connect battery

Do you have a kill switch installed?

 

[Mechanicallychallanged]

Re: DF-40 trys to start as soon as i connect battery

It tries to start with the kill switch and the ignition switch not even attached. I can remove both the kill switch and the ignition switch and the moment i hook up the battery the engine tries to turn.

 

[KB_85_V20]

Re: DF-40 trys to start as soon as i connect battery

I'm not a yamaha guy but I'm pretty sure all electric starting motors have a solenoid. Check where the wires hook up after the battery and before the starter. its probably cooked. those things are only 20 or 30 bucks. I'd unhook it and and hook up the battery. then try touching the positive battery cable to the solenoid and see if it cranks.

 

[trendsetter240]

Re: DF-40 trys to start as soon as i connect battery

It tries to start with the kill switch and the ignition switch not even attached. I can remove both the kill switch and the ignition switch and the moment i hook up the battery the engine tries to turn.

When the red cable got hot, did you disconnect it and then reconnect it? Is it possible that the Red battery cable is connected to the wrong side of the solenoid? It should be on the opposite side to the Red wire that runs to your starter motor.

 

[Mechanicallychallanged]

Re: DF-40 trys to start as soon as i connect battery

I didn't disconnect any wires in the engine. Only thing i have done is removed battery cables and the actually switch harness. I have a new switch harness, but the old one must be fine because when i installed it i get the same problem.
Im kinda leaning towards the solenoid.

 

[trendsetter240]

Re: DF-40 trys to start as soon as i connect battery

I didn't disconnect any wires in the engine. Only thing i have done is removed battery cables and the actually switch harness. I have a new switch harness, but the old one must be fine because when i installed it i get the same problem.
Im kinda leaning towards the solenoid.

Remove the heavy gauge red cable that runs from the solenoid to the starter motor. Reconnect the battery cable. (It can not crank with the starter disconnected)

Now turn the key and listen for a click. The solenoid should click each tim you turn the key to the start position. if it clicks the solenoid is still working.

Second test, turn the key to the off position. Get a voltmeter and test for voltage on the solenoid. Meter cables should be black to a bare screw on the engine and red to the solenoid where you removed the starter wire.

There should be no voltage on the starter side of the solenoid with the key turned off. If there is replace the solenoid and examine all the wires and connections in the region for shorted out connections.

 

[Mechanicallychallanged]

Re: DF-40 trys to start as soon as i connect battery

About the most professional answer a man could expect. I'm gonna be all over it first thing tomorrow . Will post my results. Thanks to everyone helping.

 

[montanabay]

Re: DF-40 trys to start as soon as i connect battery

hmmm, the solenoid shouldn't be getting power at all if the ignition if "off" and the kill switch is in, since they are redundant mechanical switches. How is your system grounded? You might have some stray current in your system, aluminum boat? When it turned over did it make the cranking "grind"?

 

[trendsetter240]

Re: DF-40 trys to start as soon as i connect battery

hmmm, the solenoid shouldn't be getting power at all if the ignition if "off" and the kill switch is in, since they are redundant mechanical switches. How is your system grounded? You might have some stray current in your system, aluminum boat? When it turned over did it make the cranking "grind"?

The kill switch is on a different circut and has nothing to do with cranking the motor.

Here's another test; after removing the Red starter motor cable, with the key in the "Off" position, listen for the solenoid click when you are reconnecting the Red battery cable. If it's clicking when you are connecting the battery then you have some stray current as montanabay suggested.

Possibly the ignition switch.