Posted By Jon on February 24, 2010

Winter 2009/2010 Blade and Carburetor REPAIRS – Sears Craftsman Model 3/20  536.884351 Single-Stage Snow Thrower with 143.943071 (D) 4171H Engine (Tecumseh HSK600-1687S)

First, I must say that this is a very good snow blower, as long as you understand its strengths and weaknesses. If you are expecting a LOT of snow, you’ll want to do your driveway in stages. For powder you shouldn’t have any problems attacking a depth of 4 – 6 inches. On the other hand, snow that is more dense (“wetter” snow that packs well for snowballs) should be cleared when it is 2 – 4 inches to avoid clogging the chute. For slushy snow, I’d say about 1 - 2 inches, but this can be  tricky. This morning, the driveway had about 2 inches of dense snow with a thin layer of slush under it in some areas. When it hit the slushy areas, it constantly clogged. The 2-stage blowers are much better for this type of snow. It’s also a good idea to clear a section of your street before your driveway so when the plow comes along he doesn’t pile up a bunch of snow at the bottom of your driveway. I got my first MTD brand (they also make Troy-Bilt, White Outdoor, Yard-Man, Yard Machines, Bolens, etc) single-stage snow blower back in the 1990s and it served me well, even though I gave it no special treatment – It sat outside most of the time, I didn’t drain the gas tank between seasons, etc (a simple machine, built well). Don’t ask me about the Husqvarna chain-saw I had – I treated it with great care, but its no-primer engine was a constant pain in the butt to get started.

At the end, a few years ago, it still did its job but it was very tired and only ran with the choke closed. It was at that time that my neighbor put his (my current) Sears Craftsman snow blower out on the street as a throw-away. I grabbed it, figuring it could be a source of repair parts, or that I could swap some parts from my old unit to make it well. As it turned out, I could find nothing wrong with it, other than it was missing one of the 4 longer rubber blades. This wasn’t a big problem as the older models have full metal blades with rubber blades as extensions… The newer models of this type I have seen only have rubber blades without the metal backing.  To repair this I removed the blade that was missing its mate, cut it in half and remounted the two short blades as a pair at the center position. To do this I drilled out the original rivets and attached the half blades with pop-rivets at first, and when a few broke, I replaced them with bolts and nylock nuts.

 Until this year, this Sears unit worked great, but in December when I tried to use it I couldn’t get it to run reliably. IF I could get it to start, it would stall out, and it wouldn’t run at all unless the choke was closed… A couple times, I got it to run for a few minutes.

WARNING – FIRE HAZARD!

The repair below involves working around gasoline.

If you decide to try this repair on your snow blower, be aware that gasoline can spill out from the fuel bowl, so NO SMOKING! If you set yourself or your house on fire while repairing your snow blower, it’s NOT my fault. It’s because YOU were not careful enough. BE CAREFUL!!

I wasn’t looking forward to clearing the driveway using a shovel, so I clamped the fuel hose (to prevent fuel flow), drained the fuel bowl, removed the bolt from the bottom of the fuel bowl (it is also the main jet) and thoroughly cleaned its orifice, which was partially clogged.

 Well, that took care of the problem, and afterward it ran like new! I wonder how many folks throw these snow blowers away without trying this fairly simple repair.

I have found that if you tilt the snow blower forward so it is resting on its “mouth”, you should be able to remove the main jet without much spillage. To clean out the small hole in the main jet, you can use anything of suitable size. I used a small drill bit pushed in and out by hand (NO drill), but the wire from a twist-tie might also do the job. The main thing is to clean it as well as you can, so fuel flows correctly.

All of my neighbors have the larger and more expensive 2-stage snow blowers, but I really don’t see the need unless you often get heavy, slushy snow.  They have more things that can break, and as a result of that, can be much more complicated and expensive (!) to repair.  They also seem to be much slower – I zip along at about twice the speed of my neighbors when I’m clearing powder snow. For slushy snow, they have me beat, as this unit tends to clog easily.

Category: The Right Guy To Call
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