Mysterious loose wire

[Moody Blue]

Found a loose wire under the cowling of my 1991 Mariner 40Hp. It is a 4cyl version. The wire seems to originate from the electrical box (I think)and the loose end is dangling around the #1 spark plug. Also noticed that beside the #1 spark plug is a blind tapped hole about 1/4" deep. Is something missing. The wire color is beige with a blue stripe. Any input would be much appreciated.

 

[threecylinder]

Re: Mysterious loose wire

Does the motor run? Run well? Is it white/blue? Almost sounds like one of the wires from the stator to the switchbox.....

 

[achris]

Re: Mysterious loose wire

That wire is for a temperature sender that screws into the hole you saw next to #1 spark plug. It's an option but the wire is already in the harness. Just throw a bit of tape around the end and tuck it away neatly. <br /><br />Chris........

 

[Moody Blue]

Re: Mysterious loose wire

Thanks for the feedback. I'm learning lots everytime I log in here. GREAT site.<br />Threecylinder<br />motor runs good - havn't had it on the lake yet but runs fime on the muffs.<br />Achris60<br />is this not required for an overtemp safety system of some sort? I have ordered a manual for the motor but it is yet to arrive. Thanks everyone for their input.

 

[KCLOST]

Re: Mysterious loose wire

It's not normally on a 40-50 hp motor, but if you have a temp guage already at the console I'd go ahead and purchase a new sensor and hook everything up... I sounds like all you need is the sensor, as that wire should go directly to the guage...<br />More importantly, you should also have a temperature switch (or overheat sensor). This will activate the horn in the event of an overheat condition... Do you see another wire going into the end cap near one of the other spark plugs? It should be a black wire, probably wrapped inside clear plastic tubing.