Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

I like the lever set up for the Toro throttle. 

I need to come up with something a little more sophisticated than a piece of nylon string under a bit of tension.  However, with mitts or gloves on, the string works very well.  I like the simplicity of the string but would like something a bit less..... (ah, what is the word I'm looking for?)....... redneck.  I have the string coming up the left side handle then across at the top about two inches below the cross member at the top.  I depress the bar that engages the paddle and work the string with one finger usually applying pressure to increase rpm. That way, I can keep both hands on the handle to have a good grip on the machine and work the throttle too.   Very functional and easy to use. 

You do nice work bud!

Very nice, jrtrebor. When working on my SS, I had thought about how to open the throttle more controllably than using a string. I thought about a bike brake lever. It would let me leave the throttle "stock" until giving the lever a squeeze. But you'd have to hold it the whole time you want to raise the throttle. I like the bike shifter idea, that seems more consistent. If you got a lever off an old bike, that had a friction-shifting system (the lever is infinitely adjustable), rather than indexed shifting (clicks to different positions), then you could even make small adjustments. But maybe the amount of cable travel between clicks won't be too much (eg- too much as in just 1 shifter click already opens the throttle fully). Nice work!

With the string set up, the tension of the governor spring pulls back and goes to low speed as soon as releasing pressure on the string.  It's the same as using the throttle on a chainsaw or leaf blower.  The more I squeeze the string, the faster the engine goes.  Relieve pressure and it slows down.  Don't look too cute but it works.

borat, are you attaching the string to the throttle on the carb directly? Or are you simply adding tension to the governor spring? It's a subtle difference, I suppose, but if you're "just" adding tension to the governor spring, then the governor is at least still involved, and will presumably try and avoid a big over-speed condition when you pull it back away from the snow, or otherwise remove the load. Whereas if you've directly held the throttle open, and you pull back from the snow, the RPM's will skyrocket. Just curious.

First thing to understand is the engine and the governor system used on it.  The machines I have rigged are Tecumseh 139cc two strokes model  HSK850. 
They have a mechanical governor which operates on a lever attached to a shaft protruding from the engine block.  The top of the lever has a linkage and spring that connects to the throttle butterfly.  I put a small wire loop around the linkage at the top of the lever to attach the string then drilled a hole in the side of the plastic housing to feed the string through then up the handle and across with enough slack not to actuate the governor mechanism.  When you start the engine, the governor lever will move slightly inward taking up some of the slack.  When running, adjust the string with just enough tension to actuate the governor when squeezed and no tension when released.


Yellow  grass trimmer string attached to copper wire attached to linkage on the governor lever.



MTD on the deck with string running up left side of handle.  Looks pretty slack but when running tension takes it up a bit but does not apply pressure on governor until string is squeezed.
The string runs across the handle is attached to the other side and is approx. two or three inches below the  handle. Doesn't look too sharp but it works.

jrtrebor wrote:
Nice lineup.   The serrated auger on the Ariens looks more aggressive, should work well with the new powerplant.

Looks like a great setup, you've got all the bases covered! or uncovered.

Yeah, I had some thin cheap stuff laying around from an electric trimmer my wife bought.  Trimmer died but the line is useful.  Problem is it doesn't tie well.  The best way to make a loop at the end is to put little dab of JB Weld Quick on the end, double it over and use a very thin piece of copper wire to hold it until it bonds then slip over a piece of heat shrink to finish it off.  Be very careful with the flame when warming up the heat shrink.  That trimmer line doesn't like too much heat. 

I'm using thin braided nylon string on the Craftsman machine.  It holds up pretty good too.