# Ignition wiring help on Ariens ST724 model 932022



## Andy Seibel (Aug 30, 2019)

Hi guys. I've lurked and gotten some useful help already, but I have one issue that I can't seem to figure out.


My ST742 model 932022 has a broken wire near the ignition. The engine is an H70 Tecumseh. The ignition switch currently does not turn of the engine. The only way I can kill it is to choke it.


One wire goes from the back of the switch cylinder to the little tab near the bottom of the throttle.


The broken wire is coming from a tab on the chassis where it meets another wire. I assumed it should be connected to the other terminal on the back of the ignition switch. I tried making contact by hand with the engine running and the throttle in the lowest position, but it still didn't kill it.


Does anyone know where that second wire is supposed to connect to? If you happen to be able to take a photo of your working machine, that would be wonderful. I took a photo with the cover off to try to show what I'm working with.


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## JerryR (Oct 18, 2016)

Andy Seibel said:


> Hi guys. I've lurked and gotten some useful help already, but I have one issue that I can't seem to figure out.
> 
> 
> My ST742 model 932022 has a broken wire near the ignition. The engine is an H70 Tecumseh. The ignition switch currently does not turn of the engine. The only way I can kill it is to choke it.
> ...


Maybe your switch is bad, did you try touching that wire to chassis ground? also grounding the kill switch should kill the engine.
The way my Tecumseh is wired: ignition switch has a red and black wires going to a bracket on the lower part of the engine. the red wire goes to chassis ground (on the bracket). the black wire goes to an insulated terminal on that bracket and is tied to 2 green wires, one of the green wires goes to the kill switch, the other green wire goes under the engine cover presumably to the ignition module.
HTH
JerryR


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## cranman (Jan 23, 2016)

You can wire in a toggle switch from the grounding wire on the coil to ground and put it on the handle bar as well.


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## Dauntae (Nov 10, 2016)

YUP the swith in the ON position breaks the contact of the wire, When the switch is off it connects the wire, One end should go to the coil and the other to ground.


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## Andy Seibel (Aug 30, 2019)

Thanks for the idead.
I did some more testing. 
I took the bare end of my broken wire and touched it all over until I could kill the engine. I had to actually touch the throttle lever. It seems the switch was not the problem, but rather the connection where the wire connects to the little rod that touches the throttle.

I tried wiggling on the tab and it broke off. So now I'm no better off than where I started. It appears that if I want the ignition switch to kill it I will need a new throttle mechanism with the wire connected to it. Since I don't really need that to kill it, I could just wire up an alternative toggle switch like cranman said.


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## WVguy (Nov 24, 2018)

Andy Seibel said:


> The only way I can kill it is to choke it.


Does the engine have a fuel valve? If it does, I've been turning off engines for years by just turning off the fuel valve and let it run until it dies of fuel starvation. In the case of a snow blower, around here it could be months before it's started again and in the meantime the fuel in the carburetor bowl can go bad. That practice helps prevent that since most of the fuel is run out.

Just a thought.


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## cranman (Jan 23, 2016)

I'd like a engine shut off for emergency.....ever have a governor fail and the engine has seconds before blowing up? A million things can go wrong and you need to shut down quick.


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## tj1 (Dec 28, 2019)

one wire comes from the coil essentially on the engine and one goes to ground. A kill switch either from a key or on the throttle when depressed all the way connects the coil wire to ground and shuts it off or kills the engine. two wires are generally connected on a little tab lower side of engine and another wire should be connected to a ground.


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## SB1 (Mar 19, 2021)

I know this has been a while but I had the same problem. But I solved it by looking at a neighbor's ST724 (one from the 1990s; mine is from 2001). The loose wire connects to the same place on the throttle control lever as the wire from the key switch. It is an insulated plastic piece and when you turn the key or push all the way down on the throttle, it closes the circuit and the engine dies. The connection point is very weak and does not allow easily reattach the wire by crimping. I was able to strip the loose wire, wrap it around the connection tab for the wire that comes from the key switch, and solder it. I hope this helps.


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