71' merc wiring problem

[Dutch515]

Hi guys, I have a 1971 (I think) merc 200 20 h.p. Im trying to set the wiring up w/o elec. start and harness. I want to be able to use the stop switch on the motor to kill the engine. I got a wiring diagram and ran into a problem. I cant find a switch box anywhere on the engine. It does not have a points ingn. Should there be a switch box? Can any of you help me out. I have some pictures here for you to look at and see what im talking about. Dutch

Notice the brown and white wires coming from the trigger, should be plugged into the switch bow but they go directly to the coils

 

[AMD Rules]

Re: 71' merc wiring problem

Hey Dutch.....

Are you sure you don't have points? The '71 20hp should.... your wiring shown and lack of switchbox suggests it likely does.

 

[Faztbullet]

Re: 71' merc wiring problem

AMD that is the correct wiring for Dutch"s motor. Just a quick note.. The push button on this system is NORMALLY CLOSED and OPENS to kill engine. In other words stop wire is shorted to ground and ungrounded to stop engine. Do not kill engine with button if running on hose muffs, use choke as you can spike stator with out back pressure on engine.

 

[Dutch515]

Re: 71' merc wiring problem

So what does that mean, you can def. see the ign coils. I just dont know what to hook up with what I have to kill the engine. I also noticed that I have no spark when I pull the motor over as is. Dutch

 

[Faztbullet]

Re: 71' merc wiring problem

This means you have high voltage stator and points system. You should have a pushbutton on engine front for killing it

 

[Dutch515]

Re: 71' merc wiring problem

Yes your right, I was thinking of the omc type internal coils, points and cond. Sorry. I do have a kill switch button but im trying to figure of how to hook it up w/o using the off/on/run type key ing. and no external harness.

 

[Dutch515]

Re: 71' merc wiring problem

Update!!! I think ive solved the problem. All I did was run a wire connected to the salmon wire coming from the stator and ran it to the killswitch. Pulled the rope and I had awesome blue spark, and when I held the killswitch and pulled the rope, no spark at all. Can anyone confirm this is ok to do cause I dont want to mess anything up. Oh and has anyone seen a plug with no bottom electrode? This motor has NGK BUHW's and Ive never seen anything like it. Thanks guys, Dutch