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

Hi all. I recently purchased a used HS621 that wasn't running too good and have begun getting it back to (or trying to) reliable service. I purchased it for my folks so it needs to start easy and work consistently. There are problems with the carb, it only runs with the choke on. I got it to a point where it'll run with the choke almost off but it surges at that point. So, a complete carb dissassembly is in order and I'll be tackling that once the gasket set comes in. In the meantime, I wanted to ask whether any of the other HS621 owners could comment on the air cleaner on this thing. This is all new to me but there doesn't seem to be any kind of air filter on this thing. Not sure if it's related, but the float bowl on the carb was full of debris and sediment. This either came from the gas or could it come from the air intake?? Like I said, I'm new to this.

The parts diagram here:
http://www.boats.net/parts/search/Honda/Snow%20Blower/0/HS621%20AS-B%20SNOW%20BLOWER%2C%20JPN%2C%20VIN%23%20SZAN-1038359%20TO%20SZAN-1099999/AIR%20CLEANER/parts.html

shows a strainer of some sort but I don't have that. Also, they don't sell it (part #8 is not in the list).
So, is the diagram correct? Does anyone else have this snowblower that can comment? If i am indeed missing this piece can I just improvise something and what would be an appropriate material to use?

Thanks
Steve

Thanks for the fast response. When I put my finger on the cam that opens the throttle plate the surging stops. This is the little cam that the throttle assembly, springs and all, control. When I move it, I can change RPM without surging. The springs are very fine and I believe I stretched one of them out, the return spring I think. I am ordering new springs. However, before I do that I'm going to clean out the pilot jet because I have not done that. I did not know where the pilot jet was when I cleaned the carb the first .. oh, three times! So I guess that could still be it. However, I do suspect the linkage as the cam moves around with the surges and that return spring appears "loose" when the throttle is in the closed position.