How to disable WOT upon shutdown (snowblower)?

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On my Craftsman snowblower there is no throttle control (cheap! cheap! cheap!), just an on-off switch, so it's either WOT/on or off. So, when it is shut down via the on-off switch it does so at WOT and sucks in a nice swig of raw, unburned fuel(you can smell it). Is all this washing off of oil from the cylinder wall something to worry about? It can't be good. Have any of you come up with a clever solution? There is no fuel shut off valve of course and no room for one unless the shields are removed and/or modified.
 
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Well, first I'd just point out that the throttle is controlled by a governor, so if there is no load the throttle is actually pretty closed and obviously under full load it is wide open. So the easy advice would be to just shut it down under the lowest load possible, and yes gas will still get sucked in but that's that. Generally the shaft that runs through the butterfly will have a wire shaft that runs to the governor, and a spring. So if you can find this linkage or spring, it should be pretty easy to throttle it down manually all the way and it should shut off, it's hard to say if there is a stop that controlls how closed the valve can go.
 
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 Originally Posted By: bepperb
Well, first I'd just point out that the throttle is controlled by a governor, so if there is no load the throttle is actually pretty closed
This. Don't confuse full throttle with full speed. Instead you could always install a fuel shutoff valve and shut the fuel off until it starts to die, then turn off the normal switch. Your carb would be nearly dry (a plus for some people on its own), you wouldn't suck in your unburned fuel, and you have much less of a fire hazard parked in your garage. If anything ever went wrong with the float valve/spring/seat you'd have the whole tank of fuel running all over the floor.
 

Nayov

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Yeah actually that's a great idea, bepperb. I think I can finagle my hand in there and throttle it down for the shut off. I had a 1990 model with a real throttle control which is how I turned it off and then engaged the kill switch which was really nice. Current model is a 2006. I bet when the new emission standards come out in a year or two this raw fuel shut down will be a thing of the past.
 

JTK

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 Originally Posted By: Craig in Canada
Instead you could always install a fuel shutoff valve and shut the fuel off until it starts to die, then turn off the normal switch.
That'll work, but I bet it runs an amazingly long time just on that last bowl full of fuel. On a smaller one lunger like this, I wouldn't sweat it. The fuel it injests on coast down will vaporize in the hot cylinder and flash off in the muffler. Joel
 

JTK

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Yep. The theory is, these smaller OPE engines run more emissions compliant at max governed speed. Joel
 
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Wow, that stinks. My craftsman (~2003 model) has an idle switch. I routinely run it lower when I walk away from it and don't want to restart it, such as cleaning steps or a stoop. I also warm my hands on the exhaust when they get too cold and my wife says I stink when I come in the house :)
 
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 Originally Posted By: 97 GTP
Wow, that stinks. My craftsman (~2003 model) has an idle switch. I routinely run it lower when I walk away from it and don't want to restart it, such as cleaning steps or a stoop. I also warm my hands on the exhaust when they get too cold and my wife says I stink when I come in the house :-)
I defog/defrost/deice my glasses using the exhaust of my 8hp Toro.
 
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