Snow blower runs rough, except under load


I have a problem with my snow blower (Sears, 8.5hp), which I bought a few years ago and use maybe 2 or 3 times a year. When I start it, it seems to be running rough, it almost seems like it's going to stall (and if I adjust the clutch too much, it does). What's strange is, when I get into the snow, it picks up immediately and runs smoothly, shooting the snow 20+ feet. When there's no snow, it goes back to running rough.
I asked my friend who is usually good for solving stuff like this about this problem, and he told me that his snow blower (an expensive brand 9hp model) has the same problem, and that his repair guy has not been helpful in trying to solve the problem over the phone (presumably he wants him to bring it in for service).
What could be causing this? I know I should probably have it serviced since I haven't done anything to it since I bought it a few years ago (but I've probably used it less than a dozen times), and probably will have it serviced this spring/summer.
Bill
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Pour some injector cleaner in the carburetor and add a generous portion to the tank. Can't hurt and may cure your problem until service. Make sure the air cleaner is clean. ______________________________ Keep the whole world singing . . . . DanG (remove the sevens) snipped-for-privacy@7cox.net

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