# Heavier impeller is better at clearing snow...???



## YSHSfan (Jun 25, 2014)

I've read that Husqvarna has a cast iron impeller which is heavier than a "typical" impeller.
I think I read on a few instances, but I also spoke to a small engines mechanic at a Husqvarna dealer (He is a friend of mine) about that and he says that the heavier impeller would give it a better performance after it gets going since it would have or keep a "momentum" ?

Can someone explain this better.
Is this true?
Would a heavier impeller have an impact on the blowers performance?


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## bad69cat (Nov 30, 2015)

I think it's probably a yes and no question. Think about swinging a hammer around on a rope. then think about swinging a a sledge. Which one do you think make the most impact? Which one is easier to swing...... same deal. The sledge will definitely have more power once you finally get it going. It will be tougher on the engine to keep it going. Does the engine have the staying power in deep heavy stuff with the heavier impeller is the question. I'd like to think they considered that in the design....


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## Bolens93 (Nov 24, 2015)

Cast iron?? I am not familiar with Husq. but....would seem to me a poor choice as it is brittle.


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## ELaw (Feb 4, 2015)

The "momentum" thing I don't buy. Not that it isn't true, I just don't think it would matter.

It's probably not practical to test this but try to imagine: suppose that with the machine in normal operation (meaning engine @ full speed and auger/impeller engaged) you disengaged the impeller clutch and immediately shoved the machine into a foot of wet snow. How long would the impeller take to stop? A fraction of a second?

Now imagine what would happen if the impeller weighed, say, twice as much. How long would that impeller take to stop? IMHO it would be a slightly longer fraction of a second.

My point being that the loads a snowblower impeller sees vary in timeframes of seconds or minutes, and a the extra weight of a cast iron impeller just isn't likely to matter in that context.

But I can see a couple of other advantages. It would make the front of the snowblower a bit heavier for those who want that. And it might be stronger, meaning the vanes would be less likely to bend back when they have to deal with rocks and things. OTOH cast iron is much more brittle than steel, so in such a case it's also possible a cast iron impeller would crack whereas a steel one would bend.


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## Kielbasa (Dec 21, 2013)

"Which one do I think will make the most impact"? The one that lands on your head after swinging it around on the rope... :laugh: 



bad69cat said:


> I think it's probably a yes and no question. Think about swinging a hammer around on a rope. then think about swinging a a sledge. Which one do you think make the most impact? Which one is easier to swing...... same deal. The sledge will definitely have more power once you finally get it going. It will be tougher on the engine to keep it going. Does the engine have the staying power in deep heavy stuff with the heavier impeller is the question. I'd like to think they considered that in the design....


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## detdrbuzzard (Jan 20, 2012)

seeing that the impeller doesn't freewheel on the impeller shaft it shouldn't make a difference if the impeller is cast or not


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## skutflut (Oct 16, 2015)

A heavier piece of metal would add a slight amount of extra "flywheel" effect, but since it's an impeller, and there are forces acting on it to slow it down all the time, (snow) I somehow doubt that this would make any difference in performance. While is spinning slower with load, the engine has to provide that much more power to get it back up to speed. Now, a larger diameter impeller might make a difference, but cramming that into an existing housing might be a challenge 

I need another coffee, hard to think like a flywheel or an impeller this early


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## detdrbuzzard (Jan 20, 2012)

skutflut said:


> A heavier piece of metal would add a slight amount of extra "flywheel" effect, but since it's an impeller, and there are forces acting on it to slow it down all the time, (snow) I somehow doubt that this would make any difference in performance. While is spinning slower with load, the engine has to provide that much more power to get it back up to speed. Now, a larger diameter impeller might make a difference, but cramming that into an existing housing might be a challenge
> 
> I need another coffee, hard to think like a flywheel or an impeller this early


seeing that the impeller is belt driven about any flywheel effect would be taken up by the belt slipping


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## ELaw (Feb 4, 2015)

Either that, or it'll just add to the flywheel effect of the motor.

I guess for me, I might rather have a cast-iron impeller if the alternative was a poorly-constructed steel one. But if the other option was an impeller made of reasonably thick steel and braced well, that's what I'd choose.


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## sscotsman (Dec 8, 2010)

An idea like this probably comes from the marketing department.

Marketing: "Will a heavier impeller result in better performance?"

Engineering: "Well, its a complicated question..in theory more weight will result in slightly more torque, but an imperceptible amount, and it depends on engine strength, because the engine has to overcome the weight, and belts are a factor, and many other things will impact the question, and also..." (rambles on for 10 minutes)

Marketing: "But it will technically result in more power?"

Enginnering: "perhaps, in theory..but probably not enough to be meaningful."

Marketing: "ok, thanks!"

Advertisement: "Our heavier impeller results in better snow throwing performance!"

I am NOT saying any manufacturer has done that! 
The above was fiction..
but I can see things like that happening, in every industry and with any product.

Scot


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## ELaw (Feb 4, 2015)

For what it's worth... from their sales literature, it seems they're promoting its durability, not its performance:









And it's got 4 blades! Like 2 weeks ago, and not like last week's model that had 3. :icon_whistling:


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## Kiss4aFrog (Nov 3, 2013)

I'm with the shouldn't make a difference camp as far as performance. Having a lighter impeller allows the engine to speed it back up sooner should it get loaded and start to drop RPMs.
I'd also rather the impeller jammed and the belt spun or the pin breaks rather than the "sledge" (rotational mass) seeing if the impeller lives or the chunk of ice, newspaper, brick, branch, ... does :wacko:

I would hate to crack it or break a chunk off as cast is a pain to try and weld. I like steel better from a repair standpoint too.


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## skutflut (Oct 16, 2015)

ELaw said:


> For what it's worth... from their sales literature, it seems they're promoting its durability, not its performance:
> 
> 
> 
> ...


My craftsman is a husqvarna in red paint. It's got a 3blade, steel with welded in gusset plates, and it seeme to be pretty durable so far. I wonder how many people break impellers?


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## Kiss4aFrog (Nov 3, 2013)

Seems very few bend them. Thank shear pins or the small roll pins that let go first !!


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## Bob Cat (Jul 15, 2014)

Impellar size ,shape ,and speed would have a performance effect but not weight. Light or heavy the impellar speed is related to sheave rpm and there is no slip there. I wouldn't want to be the guy removing a cast iron impellar in one piece 
frozen to a shaft, or be blowing snow in -20 weather and introduce anything solid into the impellar.


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## skutflut (Oct 16, 2015)

Bob Cat said:


> I wouldn't want to be the guy removing a cast iron impeller in one piece frozen to a shaft.


What??? No spirit of adventure. Just think of all the new phrases you could coin during the process!


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## Normex (Feb 21, 2014)

A few things concerning Husky's cast iron impeller is for one they have a 12" impeller and Ariens is 14" so I would doubt a big discrepancy of weight between the two. Cast iron has good compressive strength but relatively poor tensile strength but the fact you can melt it in any shape can overcome its tensile shortcoming. JMO


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## Golfergordy (Oct 29, 2014)

The distance the snow is thrown is directly related to the speed of the snow particles when they come off of the impeller, whether the impeller is heavy or lightwweight, and that speed should be the same as the impeller speed at the moment the snow separates from the impeller. A heavy impeller won't run at a faster rpm and would work the engine harder than a lightweight impeller. If you had 2 identical snowblowers - one with a heavy impeller installed, and the other with the light impeller, I think the governor would control the engine speed to the same rpm regardless of which impeller is installed, consequently, given the same snowblowers, and throwing the same snow, but with 2 different weight impellers, won't change the throwing distance. One engine will work harder than the other in the process, however. 

If you install an impeller kit, you lengthen the impeller radius by the length of the rubber sticking out beyond the edge of the original impeller, and consequently that add'l impeller radius results in add'l speed at the outer edge of the impeller given the same impeller rpm, so the snow flies further.

Another way to look at this question is to compare snow throwing distance to how far a golf ball can be hit. Most drivers have the same coefficient of restitution, so consequently, the statistic everybody talks about, related to how far the ball can be hit, is club head speed. No one in the golfing world ever talks about the weight of the club a golfer uses as an indication of how far the ball is hit. The weight of the club, however, affects how fast you can swing the club, and consequently, how fast the club head speed is. I've never heard anyone say that if there are 2 golfers who have the same club head speed, that one of them can hit the ball further than the other because his driver is heavier. 

Time for a good stiff drink.


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## lillbear (Jan 5, 2016)

It probably cast steel not cast iron. And if it's the same thickness as the regular welded impeller then there no significant weight difference.


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## nwcove (Mar 2, 2015)

Golfergordy said:


> The distance the snow is thrown is directly related to the speed of the snow particles when they come off of the impeller, whether the impeller is heavy or lightwweight, and that speed should be the same as the impeller speed at the moment the snow separates from the impeller. A heavy impeller won't run at a faster rpm and would work the engine harder than a lightweight impeller. If you had 2 identical snowblowers - one with a heavy impeller installed, and the other with the light impeller, I think the governor would control the engine speed to the same rpm regardless of which impeller is installed, consequently, given the same snowblowers, and throwing the same snow, but with 2 different weight impellers, won't change the throwing distance. One engine will work harder than the other in the process, however.
> 
> If you install an impeller kit, you lengthen the impeller radius by the length of the rubber sticking out beyond the edge of the original impeller, and consequently that add'l impeller radius results in add'l speed at the outer edge of the impeller given the same impeller rpm, so the snow flies further.
> 
> ...


im sure glad it doesnt snow golf balls.:wavetowel2:


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## YSHSfan (Jun 25, 2014)

lillbear said:


> It probably cast steel not cast iron


It says right on the picture _*"cast iron 4 bladed impeller"*_


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## Spectrum (Jan 6, 2013)

Momentum is not equal to constant work or power. Think of it as a battery that has a burst of energy, better yet, much like a capacitor. Once it is discharged or slowed down it has no advantage and will need energy above the continuing load to accelerate making it a disadvantage. Since a snowblower load is relatively constant within a loaded period having a burst of peaking power does little to get the job done and as said could very well be a disadvantage.

Pete


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## dman2 (Sep 22, 2019)

The only advantage a heavier impeller has is that it makes things a little bit smoother. It works exactly like a flywheel, or heavy rims/tires on cars. It takes longer to speed it up, or to slow it down.

You think it won't make much of a different, but it does. A car with a heavier flywheel will shift a lot smoother and you don't have to step on the gas petal as much to keep it constant speed. It might help reducing wear on the valve springs and things like that, but it does wear out the brake pads sooner. It also save the brake pads, because it has more engine braking power.

In racing, people prefer lightweight flywheel and wheels. It shifts rough, but it flies, once you stepped on the gas petal. You save gas if you drive conservatively, but most people don't.

Snowblower is the same, but it has less noticeable effects, since everything on it is smaller scale. Therefore, I would say that it doesn't matter and a marketing thing that they came up with. I would rather have a lightweight impeller so that it is less likely to be out of balance and easier on the ball bearing. Not too lightweight that it is going to break on me.


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## dman2 (Sep 22, 2019)

Swinging a sledge hammer around, in a circle might not be more tiring. It is because, you don't have to swing as much and you can tilt your body when doing that. It is a counter-weight and give you body balance.

Swing a hammer might be more tiring if you swing it a lot. You don't have counter-weight. You lost your balance and get dizzy much faster doing it.

Engine is the same. It wants to work. It doesn't want to just idle high. So, give it a sledge hammer to swing.

Hard to explain, but it works both ways. I just didn't think they would discuss that in snowblowers.


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## tabora (Mar 1, 2017)

dman2 said:


> The only advantage a heavier impeller has is that it makes things a little bit smoother. It works exactly like a flywheel, or heavy rims/tires on cars. It takes longer to speed it up, or to slow it down. You think it won't make much of a different, but it does...


It sure does! I just transplanted a Honda GX240 from an HS80 onto a Garden Way (pre Troy Bilt) shredder/chipper that has a 14lb flywheel plus the entire shredder assembly spinning. If you throw in the clutch to disconnect the drive and turn off the motor, the chipper will continue to spin for almost a minute. If you don't throw in the clutch, the chipper will spin the non-running motor for close to 30 seconds.


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## HillnGullyRider (Feb 9, 2014)

I don't know but I've thought of transplanting the Husky impeller onto the Ariens compact just to see if it might fit and test it out. It's interesting that that literature states "High Speed" impeller. Ariens also does this, only they say "High Speed steel" impeller but it's only for certain models like the Platinum, on most models they just state "Steel" impeller. The Husky cast impeller won't work on the full size Ariens because they take a 14" impeller while the Husky's largest cast impeller is 12". Ariens also made a four blade 14" impeller once upon a time, Perhaps their research decided 3 blades are better for balance and maximum throwing.


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