Kill Switch (1973, 18hp Evinrude)

perkdp

Petty Officer 1st Class
Joined
Sep 25, 2002
Messages
237
My kill switch is causing one cylinder to not fire so I disconnected it. I thought the switch base was plastic thus not gounded to the motor but it must be grounding out one cylinder without pressing it. <br /><br />My question: Can I hook up any ole switch that when pressed/closed will ground out the points/coils ?<br /> example:<br /><br /> ________________ point 1 <br /> Run | \___ coil 1 <br />gnd <---\---|________________ point 2<br /> \___ coil 2 <br /><br /> ________________ point 1 <br /> stop | \___ coil 1 <br />gnd <-------|________________ point 2<br /> \___ coil 2 <br /> <br />or will that set up burn a coil or condenser<br />?
 

Paul Moir

Admiral
Joined
Nov 5, 2002
Messages
6,847
Re: Kill Switch (1973, 18hp Evinrude)

The ignition switch is just a plain, normally open pushbutton. It does not ground out the points as such, but rather connects the two together. This has the effect of shorting out both points which kills spark on both cylinders. You see, spark happens when the point is opened, and when one opens the other point is closed. So the coil never "sees" the point open.<br /><br />Even a little moisture in the kill switch can cause loss, or partial loss of spark. <br /><br />Is this that gremlin you've been chasing?<br /><br /><br />When trying to write ASCII art on this BB, you need to surround the area with {CODE} {/CODE} (replace { with square brackets). Otherwise it eliminates any spaces.<br /><br />Ten spaces: Done.<br />
Code:
Ten spaces:          Done.
 

perkdp

Petty Officer 1st Class
Joined
Sep 25, 2002
Messages
237
Re: Kill Switch (1973, 18hp Evinrude)

that drawing didn't turn out at all. it looks good in "edit"<br /><br />that's just one of the gremlins. i found it pretty quickly and disconnected the kill switch. <br /><br />but now that it runs better, i'd like to hook one back up.
 

Paul Moir

Admiral
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Nov 5, 2002
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6,847
Re: Kill Switch (1973, 18hp Evinrude)

If it's the kill switch I'm thinking of, the chromed push button that normally has a rubber protector cap over it, it's really easy to find. I've seen it at a number of marine suppliers, auto supply stores, etc.
 

lilyduck

Cadet
Joined
May 11, 2005
Messages
11
Re: Kill Switch (1973, 18hp Evinrude)

What Paul said.<br /><br />This is real easy to find OMC still makes them. There about 45.00 bucks. If you wanted to go with a tether there a little cheaper about 10-15 bucks I dont know why the price difference but the tether gives you a sense of security if fallen or ejected from the boat.
 

perkdp

Petty Officer 1st Class
Joined
Sep 25, 2002
Messages
237
Re: Kill Switch (1973, 18hp Evinrude)

So.... on a "closed switch" it would be just like touching the two wires together. <br /><br />Open switch would be wires apart. <br /><br />I must have gounded one of the wire on my old switch when I tried to solder / fix.
 

Paul Moir

Admiral
Joined
Nov 5, 2002
Messages
6,847
Re: Kill Switch (1973, 18hp Evinrude)

Exactly. <br />Fortunately, back in those days OMC was mostly using standard switches. For example, the safety switch on my 28hp is the same as the lid switch in my washing machine. Those same kill switches I've seen for $5-$20.<br />But a tether type kill switch would be a really good idea too. I see Iboats sells generic ones.
 

perkdp

Petty Officer 1st Class
Joined
Sep 25, 2002
Messages
237
Re: Kill Switch (1973, 18hp Evinrude)

Thanks guys. <br />I put one of those $5 switches on an ole mercury I have (they wanted $60 I believe for a new one) and it works like a champ. On it, one side goes to ground and the other goes to a primary coil or something (it has the lightening cdi or whatever the call it. no points)<br /><br />You guys make this Iboats forum a nice place to hang out
 
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