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

what size pulley should iput on 305cc engine there is a 51/2'' pulley on blower .it is a 36' cut blower for a lawn mower but i am modifying to go on atv .its a single stage so i want to get most power i can out of it.any help would be appreciated thanks..

ok thanks for your info ,mine is the same driven pulley on shaft with sprocket auger ischain driven.

josjay, just thought of something else. On this type of blower, the distance between the auger and the housing is critical for distance. Make sure your auger is in close. If you can adjust it, great, if not, then make up something similar to a Clarence kit for the two throwing paddles. Also, they throw a lot better when the auger is kept full, so keep up your forward speed in light snow. Now that I can see your pic, it's not a lot different than mine except for length. My driven pulley is centered on the housing (longer shaft) because it comes off of the front PTO. This pic (if you can see it) shows a 20HP driving a single stage 48" blower. http://www.mytractorforum.com/attachment.php?attachmentid=145587&d=1298832440

got a 4'' pulley today could not find a 4 1/4 will try this one soon as i get time will let know how it works. thanks alot for info i understand how a pulley system works alot better now.bill h i seen your pic it throws snow good what is a clarence kit.

Just search here for 'clarence impeller kit'. You'll only need two pieces for your paddles. If you can adjust your auger within 1/8" or 3/16" of the housing you may not have to.

ok i tried the 4' pulley today it did not work very well it would stall engine very easily.then tried a 3 1/4' but not work as good as a3 1/2. so i guess the 31/2 is the best im going to get work not bad throw snow 10 feet  would like to get further but dont know what else to do also was very wet snow chute plugging up.

Put a big Vangard V-twin on it.  The additional power will allow a lot of pulley size flexibility.

Not surprised the engine didn't have enough to drive a 4" pulley and turn a 36" blower.  That's asking a lot of a 10hp engine.  Your probably going to need something like a 16hp to really get things going.
Or as borat suggested the Vangard V-twin would certainly give you what you need.

would bigger pulley on bottom make any difference or would i be wasting my time.

A bigger pulley on the bottom (driven pulley) would help some with the engine bogging down problem.  But using a larger "driven" pulley is going to drop the RPM of the shaft.  So the auger
RPM will be dropping as well.  Your throwing distance will suffer.  The Blower width, auger RPM, pulley/sprocket combination and engine size are all engineered to work together. If you drop the HP
that the system was designed to be used with.  There really is nothing you can do to get around the lack of power.  You can always increase the power/HP driving a designed system and improve the
blower performance.  But you can't go the other way and offset a lack of engine power by changing the gearing so to speak. 

Bill H has a 48" blower on his tractor which I know is 12" wider than yours.   But he also has a 20hp engine.  That's twice the size of yours, roughly.  I'm afraid you only real option is to get a larger engine.
A 16hp would probably do it.  And as was suggested reducing the clearance between the throwing portion of the auger and the housing is also important. 
If you want to get the maximum performance out of the blower.

As a single stage blower owner and being extremely jealous of all of you knowledgeable 2 stage owners I read all of these threads with great interest. I was thinking about the issue of impeller and auger housing clearance and thought about the possibility of using something like a roll-on truck bed liner like dupli-color bed armor or something similar. Enough coats would probably help with the auger clearance while protecting the housing at the same time. Good idea or bad?