# Snow blower modifications



## CrazyCarl (Jan 21, 2014)

I purchased a used MTD 24 inch 8 hp this spring. I'm not sure of the year and haven't had too much luck figuring it out yet. Seemed to run ok then, but when I started it up this winter it didn't run too well. A new carb later and the engine runs great. Now that I've used it for a while I'm thinking of some modifications and being this is the first snow blower I've used since I was a teenager I figured I'd crowd source some opinions.

The snow blower runs great, but it seems that I've got to load the engine to really get it to throw far. Even the recent foot we got just made it work just above idle. But when I got into the 18-24 inch tall drifts it loaded the engine enough to get it to throw decent. I was thinking about a smaller impeller pulley to increase the impeller speed as well as lessen the mechanical advantage of the engine, making the engine work a little harder to move more snow. 

I was just reading about impeller kits as well. Any opinions on those? do they work that well?

I was also thinking about a chute modification. The current chute shoots the snow at a lower angle than I would like. I have a hedge to clear, and the blower barely does it this year. It probably won't make it over it next year. Is it as simple as a new plastic piece for the top?

Any opinions would be appreciated. I'm mechanically inclined but new to snow blower modification. Thanks in advance.


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## Shryp (Jan 1, 2011)

MTD probably isn't the best starting machine for making improvements to, however that is what you have now so we can work with that.

Throwing better with a load has more to do with the impeller being full than the engine being loaded. All snow blowers work better when they are working at full capacity.

Impeller mod is a good investment.

Good pneumatic snow tires are a good investment as well.

Never tried a modified chute, but it couldn't hurt. That is something I have been interested in.

Changing pulleys will give you more distance as well. Most people go with a bigger pulley on the engine, but a smaller one on the impeller will do the same thing. Spinning the impeller faster could put more wear on the front gearbox and parts up there.

There has been a lot of talk about the armor skids. Looks good on paper and I will probably get a set when I need new ones.


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## CrazyCarl (Jan 21, 2014)

Thanks for the quick reply. The MTD may not be the best, but I did get it for a pretty good deal. That leaves me a little room for some mods . Is there a formula or general guideline for pulley changing? I have some close neighbors so I can't throw it too far. Just looking for a little more distance when I need it.

I try to run the blower pretty fast to keep it full, but when I run it that fast snow dribbles out the side and leaves little snow lines. I was hoping a pulley mod or impeller kit would help eliminate that.

At least the tires and skids are good right now, and blowing over grass should help both last for a while.

The chute looks like I could just cut some off of the back end to increase the throw angle, I was thinking of getting a new (or used) plastic piece and giving it a try. Don't think It could hurt too much.


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## Shryp (Jan 1, 2011)

For pulleys you want to keep the impeller under around 1300 RPM.

engine RPM x engine pulley diameter / impeller pulley diameter will give you the rpm.

So 3600 x 3 / 9 would be 1200 RPM at the impeller.


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## CrazyCarl (Jan 21, 2014)

More good info, thanks. From reading the DOM code it looks like mine is an 03. Newer than I thought. Is there a good place online to buy a new pulley? What about the belt? Is that just measured after the new pulley is installed or is there a large amount of idler adjustment?

I'm thinking a larger engine pulley will be better than a smaller impeller pulley. That way I can gain a little more ground speed also. 

I forgot to mention earlier that I did have to mess with the governor arm. I don't have a way to check RPM's but it does pass the ear test. All I did was make sure that at full throttle the governor arm was just barely not maxed out. The first time I maxed it out and it ran a little too fast. Is there a different way to do this to make sure my RPM's are correct?


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## Shryp (Jan 1, 2011)

You need a tachometer. Some are digital and work off spark plug pulses and some are mechanical and work off engine vibration. There are also the photo ones that use a light sensor and some reflective tape.

The engine pulley sizes should be close enough to each other that the stock belt should have enough adjustment. If that fails you can always go up or down a size.

For pulleys I would go to one of these places.

Pulleys & Idlers | Lawn Mower Parts | MFG Supply -- I bought mine from the Steel V-Belt Pulleys section.

Phoenix Manufacturing Product Catalog -- Gustoguy bought his here, but thinks he spent too much.

Machinery Parts, Domestic items in Redsheller's Store store on eBay! -- This is a recent find from someone else.

Tractor Supply Co. - - Home Page -- I bought some here at a retail store, but they were 5/8" width so the belt ran pretty low in them which made measurements difficult.


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## detdrbuzzard (Jan 20, 2012)

the armor skids are a big improvement if you have uneven pavement, i have them on all three of my two stage toro's
my 521E came with a short chute and i replaced it with the taller chute ( about 3.5 inches taller ) from a later model 521 and it did help with the distance the snow was thrown, a bit higher and farther


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## CrazyCarl (Jan 21, 2014)

Thanks for the links, I'll check them out. Looks like the first thing to be done will be to make my own impeller kit this weekend. I've got a local tractor supply, maybe I'll check into a pulley there.


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## detdrbuzzard (Jan 20, 2012)

take a look down the chute, is the opening round an open or square ? my little craftsman 5.5/24 has a square opening that is really the choking point of snow exiting the machine


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## SlowRider22 (Oct 17, 2013)

As for pulleys, I'd recommend only a half inch difference from the stock pulley..._maybe_ up to one inch.
A smaller pulley will increase torque on the impeller & auger, but causes more wear and tear on the gearbox and the associated components. It also makes the engine have to work harder than it should.
A larger pulley gives more mechanical advantage to the impeller & auger so it technically gives it more power.
Personally, I have a half inch larger pulley on my 13/32 and it works wonders.


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## woodtick007 (Apr 9, 2011)

Shryp said:


> For pulleys you want to keep the impeller under around 1300 RPM.
> 
> engine RPM x engine pulley diameter / impeller pulley diameter will give you the rpm.
> 
> So 3600 x 3 / 9 would be 1200 RPM at the impeller.


Is 1300rpms posted in some service bulletins issued by the Snowblower manufactures? What happens if you go above 1300? Does it shorten the life of the gearbox? As you know many better made blowers have sealed ball bearings on the impeller shaft...and others have some sort of bronze bushing.


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## woodtick007 (Apr 9, 2011)

SlowRider22 said:


> As for pulleys, I'd recommend only a half inch difference from the stock pulley..._maybe_ up to one inch.
> A smaller pulley will increase torque on the impeller & auger, but causes more wear and tear on the gearbox and the associated components. It also makes the engine have to work harder than it should.
> A larger pulley gives more mechanical advantage to the impeller & auger so it technically gives it more power.
> Personally, I have a half inch larger pulley on my 13/32 and it works wonders.


Do you mind if I ask where you purchased your larger pulley? Would PM me the link to the webpage?


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## Shryp (Jan 1, 2011)

1300 is just what most recommend. There is a point where you just cause wear and tear on parts and it is possible to spin it so fast snow won't even have time to get in it.


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## woodtick007 (Apr 9, 2011)

Thank you


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## CrazyCarl (Jan 21, 2014)

Shryp posted a few links for pulleys. Looked like most were around 10 bucks. 

I'll check out the chute this weekend when I do the impeller mods. It seems to stay clear, it just has a very low maximum angle. I'm thinking of trying out a mocked up deflector made of aluminum. Then maybe modifying my deflector from there.


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## CrazyCarl (Jan 21, 2014)

Put the impeller kit on this morning, and can't believe the difference it made. My impeller had a 5/8" gap between the impeller tip and the chute housing. Pretty extreme. We had a pretty good winter storm last night and this morning. That allowed me to try it out nicely today. The blower maybe blew 12' feet under ideal conditions before. Now it blows 20' easy. The best part is that now it blows just a few inches much better. Before it would only kick the thin stuff out 6' or so, now it throws it almost as far as the thicker areas. I am genuinely amazed that just closing up a gap would make such a huge difference. It really blows better than I thought it even could. Just doing that has made me pretty satisfied with the blowers performance, I don't think any more mods are needed.

The kit cost me about $30 to make. Finding the rubber was the hardest and most expensive part. I ponied up $20 for a nice thick mudflap. The best part was my neighbor offered me $35 to clear her driveway, Kit paid for in 15 minutes .


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