retrofitting a kill switch

[Wreck Rider]

Hi Guys<br /><br />Wondering if adding a kill switch to an old outboard that never had one is really as easy as the guy at the parts counter says, has anyone done it recently and would like to share the experience?<br /><br />My nephew (10 yrs) recently received a hand-me-down 8-10' aluminum fishing boat, complete with a really old 3 hp evinrude outboard, and his Dad won't let him go out alone until we install a lanyard-kill switch (which I think is a great safety idea by the way).<br /><br />I bought a kill switch today and the instructions rely on some specific wire colour codes inside the engine, I'm wondering if I should expect surprises!<br /><br />By the way, sorry to be vague but I don't know the model, year, or serial number and can't check for a couple of weeks (engine is in storage). I do know it's a single cylinder 2 stroke evinrude and its pretty old.

 

[rwise]

Re: retrofitting a kill switch

Give the model of the engine that will help. I have installed kill switches on both of my 58's. One is a johny 35hp and the other is a rude 50. it was easy on both. the 35 I just ran two wires, one from each set of points to the kill switch. The 50 has a mag. and only needed one wire grounded.

 

[CATransplant]

Re: retrofitting a kill switch

Rwise,<br /><br />It's even easier than that. On the '58 35, there are two black wires that come down from under the flywheel. Install the kill switch in either of them, running one wire from the kill switch to ground. Splice the other wire into either of the two black wires, leaving it connected to whatever it was connected to.<br /><br />On the old 3hp, though, it could be a bit more difficult, since you'd have to make a connection to the points, and that might involve pulling the flywheel. It's easier on a remote engine, since there's is a wire for the kill switch already in place.

 

[Wreck Rider]

Re: retrofitting a kill switch

New Info!!<br /><br />I got part of the story wrong but now have some accurate information.<br /><br />The motor is an Evinrude Fisherman, 6 hp, serial number 6002 BC 82052.<br /><br />I'd appreciate help with age of the motor, and does anyone have helpful hints for installing the kill-switch?<br /><br />I don't have a manual (though I should have one of course!)

 

[Wreck Rider]

Re: retrofitting a kill switch

^

 

[CATransplant]

Re: retrofitting a kill switch

That's a 1970 6hp. Let me go look at something regarding your quest for a kill switch.

 

[CATransplant]

Re: retrofitting a kill switch

OK. That engine is the old style two-coil magneto system, but it doesn't come equipped with the wiring required to add a kill switch easily.<br /><br />In order to add one, you're going to have to pull the flywheel, then add wires to the point circuit, snake them down through the armature plate and wire them for the kill switch.<br /><br />It's not a huge job, but anytime you have to pull the flywheel, it's more than child's play.<br /><br />I can't give you the exact wiring for this, but if you're still interested, someone will explain it. Just post back into the thread and it'll get noticed.

 

[Wreck Rider]

Re: retrofitting a kill switch

I'm still interested in wiring the kill switch so sure would appreciate some help on exactly how if anyone knows. I'm pretty good with electrics and mechanics so I'm not intimidated yet.<br /><br />Thanks CATransplant for a good start, too bad the answer wasn't something a little more simple but that's life.

 

[Xcusme]

Re: retrofitting a kill switch

Adding a kill switch for the older magneto systems is pretty easy. You will have to pull the flywheel. Attach a stranded wire to each set of points (the condenser is attached to the same terminal on the point set). You should have 2 wires, one going to each set of points. Route these two wires thru the bottom of the armature plate. Make sure they don't foul any other wires or linkages. Attach these two wires to the two terminals on your new kill switch. When the kill switch lanyard is attached , the switch is electrically 'open'(not shorted), the motor will run normally. When the kill switch lanyard is pulled, the switch closes and effectively 'shorts' both sets of points, killing the spark, thus, killing the motor.<br /><br />BTW, I'd use crimp-on ring terminals on the 2 wires under the flywheel. They keep the wiring neat and make solid connections too. Be sure to use stranded wire too, 16-18 ga. should do nicely. These wires will be flexing with the armature plate rotation.

 

[Wreck Rider]

Re: retrofitting a kill switch

So... that means I'll be shorting the one set of points to the other set but not to ground. How do I determine which side of the points to use? It sounds pretty easy but I'd also like to understand, without a wiring diagram its not obvious to me why that will stop the engine.<br />??

 

[CATransplant]

Re: retrofitting a kill switch

Connect to the same side that the condenser wire goes to. Once the points are shorted to each other, the path goes to ground on the set of points that is not open. Works a treat to kill an engine.<br /><br />If you do this, route the wires carefully, since the armature plate moves. It's a good idea to put a protective tube of some kind that will resist abrasion, and make sure the wires can't interfere with the flywheel in any way. Since the engine wasn't designed with this in mind, use your best ingenuity. There's not much room under the flywheel. You may find a way to add a small clip screwed to the armature plate to secure the wires down, so they can't ride up and conflict with the rotating flywheel magnets.

 

[Paul Moir]

Re: retrofitting a kill switch

You've got it!<br /><br />There's only one terminal on the points, the other is connected directly to the engine block (ground). It works like this:<br /><br />When the point opens, the magnetic field in the coil is collapsed and you get a spark. When one point is open, the other is closed. So when you connect the two together, the point that opens is shorted to ground by the other (closed) point. So neither coil ever 'sees' it's point open. Nifty huh?

 

[CATransplant]

Re: retrofitting a kill switch

Paul,<br /><br />Just in case the gentleman doesn't have a manual, what's the proper torque for the crankshaft nut on his 1970 6hp?

 

[Wreck Rider]

Re: retrofitting a kill switch

Looks like I stumbled on a pretty good general article, in case anyone's interested have a look at....<br /> http://www.duckworksmagazine.com/05/columns/max/3/free.cfm

 

[Wreck Rider]

Re: retrofitting a kill switch

Once again a great pile of helpful information guys, thanks a bunch. Several people told me it was pretty simple but there's a big difference between that and feeling the confidence!<br /><br />Thanks again.

 

[Wreck Rider]

Re: retrofitting a kill switch

Successfully installed and tested. I had to drill a hole in the armature plate, then tie-wrapped the wires to a fitting on the underside of the plate so all the flexing happens outside the points chamber (that way it will fail in a place that's easy to get at if it fails at all, and it removes chaffing motions in the drilled hole).<br /><br />My brother and nephew are pretty pleased!

 

[CATransplant]

Re: retrofitting a kill switch

Good job! That'll make the boat and outboard much safer!