By: Author John Cunningham. Published: 2021/06/21 at 11:58 am
A snowblower that won’t move the snow is worse than useless. On the upside, this is a pretty easy problem to fix. I’m a mechanic, and an auger that lacks oomph is common in my workshop.
Snowblower augers commonly stop in the snow because the auger drive belt lacks sufficient tension. Adjusting or replacing the auger belt will most likely fix the issue.
In this post, you’ll learn why your snowblower auger stops in the snow and what you can do to fix it right now!
Snowblower Auger Lacks Power
Moving snow is tough work; a misbehaving snowblower just makes the whole task frustrating. I know what it’s like; snow has to be moved, so it’s fix the blower or start shoveling. Forget the shovel for now; I think we can fix this.
The auger commonly fails to turn in heavy snow because the belt used to transfer engine power to the auger is too loose.
We simply need to adjust so that the belt is taught when it’s supposed to be. Although this is the most likely cause, it’s not the only possible cause. Belt wear is another common cause of poor auger performance, so we’ll cover checking belt condition in this post too.
But first, we’ll look at the most likely cause (loose belt) and how you can fix it.
How The Auger Belt Works
Don’t worry; I’ll make this super fast. I know you want to move snow, not become an expert snowblower mechanic.
A snowblower is fitted with two belts, both driven by pulleys on the engine crankshaft.
The first belt (the smaller of the two) drives the wheels (drive belt), and the second larger belt (positioned nearest the auger) drives the auger pulley (auger belt) and, consequently, the auger assembly.
We are only concerned with the larger belt positioned farthest from the engine, the auger belt.
The auger belt setup commonly employs the following:
- Pulley on the engine crankshaft
- Pulley on the auger assembly
- Tensioner arm with adjustable idler pulley
- Auger lever (at handlebars)
- Auger lever cable/rods
With the belt assembly at rest, the auger belt is loose, and no power is transferred to the auger.
Pulling and holding the auger lever causes the tensioner arm with an attached idler pulley to apply tension to the belt, consequently transferring engine power to the auger. Simple setup, right?
Next, we must access the belt and check the belt tension.
You may find the auger component overview helpful.
Accessing Snowblower Auger Belt
First, we need to make working on our snowblower safe; to do that, we’ll need to remove the plug wire. Pull and twist to remove, and set it away from the spark plug.
The process for removing the belt cover is as follows:
Remove two fastener bolts on either side (10mm or 13mm). Wiggle it loose and pull it straight upwards
Checking Snowblower Auger Belt Tension
With the cover removed, go ahead and identify the auger belt. Remember, it’s the larger belt of the two, positioned closest to the auger.
Notice also the tensioner arm with the attached idler pulley. (Idler pulley is so-called because its sole function is to deflect the belt-idler)
A helper would be great about now; if not, use a clamp to hold the auger lever on at the handlebars.
With the auger lever applied, check the tension on the auger belt. Deflect the belt with your finger at its longest throw and access deflection.
Does it look loose? About a 3/16 inch (5mm or so) deflection for every 12-inch (300mm) span (pulley axle to axle). Don’t sweat this detail; if your instinct is, it’s loose, then it’s loose)
If it is loose, it will require adjustment. But before we go to the trouble of adjusting the belt, let’s check its general condition first; no sense in adjusting a spent belt.
Checking Auger Belt Condition
Most snowblower auger belts are V-type belts. So-called because of their shape. Belts work really hard and are often forgotten about until there’s a problem.
Check your belt and replace it if it looks spent. Typically as a belt wears, it suffers from one or more of the following issues:
Stretching or breaking – caused by wear and tear
Blistering – caused by slip (loose belt)
Glazing – polished friction surface caused by slip (loose belt)
Cracking – wear and tear
Stripping – excessive heat or impact
Burning – Excessive tension
Flat spots – caused by loose belt and results in excessive vibration
Hard belt – Old age
As the V aspect of a V belt wears, it allows the belt to sit further into the V of the pulley. This causes the belt’s inside diameter (ID) to become larger. The larger ID causes less tension on the belt.
Less tension on a belt (loose) causes slip and heat, which causes a belt to wear prematurely or glaze.
One of the best ways to improve snowblower performance is to replace the belts. Many snow blowers don’t see a ton of action, and while the belts may not be worn, they do get hard with age, and a hard belt causes slip.
In the workshop, I routinely examine and replace the drive belt if needed while replacing the auger belt.
Adjusting Auger Belt Tension
Adjusting belt tension takes little effort and only a few wrenches. Some snowblowers may allow for two ways to adjust the auger belt tension. The usual way is to adjust the handlebar control lever cable. The second way is to adjust the idler pulley.
We’ll adjust the handle lever cable in the following guide. The process is as follows:
Release the handle and identify the adjuster.
Open the adjuster lock nut
Remove cable slack by turning the adjuster clockwise. Test belt deflection again, and if happy, tighten the lock nut.
Replacing Auger Belt
Replacing the belt isn’t as tough a job as you might imagine. You already know how the setup works. Understanding what will aid in the replacement procedure.
Mission-critical is belt length; getting this wrong will mean you’ll be back visiting this problem soon, if not immediately.
A belt that’s too long will either not work at all or, as you know, slip. A slipping belt may cause the belt to burn and smoke
A belt that’s too short is bad also. A short belt causes the auger to turn even though the lever is in the off position. It’s not uncommon for this problem to present only when the engine pulleys warm up.
Ordering Auger Belts
All belts are coded and also sport and measurement. I don’t advise measuring the belt; that rarely works out. It’s best to check with the manufacturer and order by code.
I like to fit the best quality Kevlar belt I can because I don’t want to come back and visit this again any time soon.
It is possible to read the code from the old belt. However, be mindful that unless you know the machine, a previous repairer could have fitted an incorrect belt. (bitter experience and I don’t want to talk about it)
Auger Belt Fitting
Confident you have the correct belt at hand, the replacement process looks like this:
Turn the gas tap off
Remove plug wire and plug (may need to remove engine covers)
Cover gas tank neck with plastic
Remove belt cover
Remove belt keeper
Crank over engine slowly while forcing belt across the pulley, and continue to turn over the engine until the belt is free
Turn snowblower upwards onto auger bin
Remove belly pan
Remove auger pulley belt guide (& brake)
Remove the old belt
Be sure the belt is correct, an OEM belt costs a few dollars more but they are worth it.
Fit the new belt as follows:
The fitting process is simply the reverse of the removal process. Feed new belt from the top side
Fit new belt around the auger pulley
Refit belt guide
Fit belly pan
Place snowblower back on wheels. Offer the belt to the crank pulley and slowly crank over the motor until the belt seats.
Check the belt is seated in the pulley V and that it’s fitted around the back of the idler pulley
Check and adjust belt tension as per above and then refit the belt cover
Turn gas on
Fit plug, wire, and refit covers
You may also consider replacing the drive belt while replacing the auger belt. It is only a little extra work and won’t cost a ton. You can check out the snowblower drive belt replacement here.
- About the Author
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John Cunningham is an Automotive Technician and writer at Lawnmowerfixed.com.
He’s been a mechanic for over twenty-five years and shares his know-how and hands-on experience in our DIY repair guides.
Johns’s fluff-free How-to guides help homeowners fix lawnmowers, tractor mowers, chainsaws, leaf blowers, power washers, generators, snow blowers, and more.