# Auger Idler Tension Pulley Smoking My New Belt



## mzblues1

Hi,

First day on forum. Forgive me if this is the wrong place for my post or it has already been addressed (although I couldn't find it).

I have a Yard Machines (MTD) 611 series 24" Snow Blower Model #31AS611E352

Just replaced (from MTD directly):
1. 712-0116 Lock Jam Nut 3/8-24
2. 756-0178 Flat Idler
3. 784-5632B Auger Idler Arm
4. 710-0459A Hex Cap Screw 3/8-24 x 1.50
5. 738-0281 Shoulder Screw
6. 736-0167 Wave Washer
7. 732-0611 Extension Spring

And got a new 731-1324 Belt Cover (which I modified, because I am tired of having to buy a new one every time a belt breaks). FYI: When the belt breaks, it cuts a long hole through the top since it is cheaply made of soft plastic. So I got a piece of sheet metal and cut it to fit inside the cover so that the next time the Auger Belt breaks, the cover won't get ruined (see attached). I also think it will keep the belt from falling off as often.

Anyway, back to why I am on here in the first place.

I have read a lot of stuff both on this forum and in Google searches about getting the Auger Idler Tension Pulley adjusted properly. However, these all seem to address whether the pulley is too tight or too loose, which generally gets fixed by getting a new un-stretched Auger belt or adjusting the cable's tension, so that it is loose enough to not turn the Augers when not engaged, and tight enough to turn the Augers properly when the handle is down and the Idler Tension Pulley is engaged against the belt.

My problem is that when the handle is down fully engaging the Idler Tension Pulley against the belt, it seems to be too tight and the belt actually starts smoking. Which I assume is not good and will quickly wear out the new belt. 

Here's the difference: The belt is brand new along with the other parts that I mentioned above. The cable is properly adjusted so that the Auger doesn't turn at all when disengaged, but starts the Auger great once engaged.
The problem however is that the movement (or swing) towards the belt is too much if the handle is pressed more then slightly down, and smokes the belt more and more the more the handle is flattened. I literally have to loosen the cable all the way so that it has a couple of inches of play in it so that it doesn't tighten the pulley until the handle is almost all the way down. Which is obviously not good as the cable might fall off or get damaged just hanging like that.

So my question is, how can I regulate the amount of movement that the Auger Idler Tension Pulley is allowed to move, so that it doesn't continue to press any harder against the belt and stops once the belt is tight enough.
Is there a "stop" or other adjustment that will prevent it from moving such a big distance when engaged?

BTW: There are 2 holes on the new Auger Idler Arm that can be used and I have it in the outer one which would allow it to move close to the belt the least.


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## skutflut

Perhaps you could post some pictures of the belt, idler and pulley assembly. That's where the problems are and maybe somebody will see something out of the ordinary or misplaced. 

The cover photos are not much help, but that fact that you go thru that many belts and the blow the cover apart when they go leads me to believe something is put together wrong in that machine, maybe from day 1


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## skutflut

One other question, are you replacing the belt with an OEM or equivilent belt, of something else? 

Snowblower and other power equipment belts are not the same as automotive belts.


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## mzblues1

I find that the OEM Belts are not very strong, so this time I got Pix Snow Blower Belts made with Kevlar replaces MTD Belt 754-0430A, 954-0430B. They claim to be stronger?


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## skutflut

mzblues1 said:


> I find that the OEM Belts are not very strong, so this time I got Pix Snow Blower Belts made with Kevlar replaces MTD Belt 754-0430A, 954-0430B. They claim to be stronger?


I dunno about Pix belts. They are made in India. Are you sure they are Kevlar? Does your machine have dual auger belts, seems I saw a picture showing two belts for auger replacement. Did you MTD belts smoke or just break?


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## mzblues1

Honestly I don't know if the OEM's smoked or not since they were always covered before they broke. However, I have replaced at least one per year when using them.

Regarding the Kevlar Belts, it says it is, so I can only hope that they are being truthful. They actually are cheaper then OEM, so I figured it was worth the try.

Here are the images that you requested.


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## bad69cat

I have found out the hard way that belt alignment in critical. First, check that the engine mount bolts are tight. then look at the pulley alignment when you have the drive lever engaged. That way you can see the belts tension and alignment when it's in operational mode. It needs to be straight and have decent tension on it. If you need to loosen up the motor mount bolts and adjust them accordingly. Having belts that are designed for th machine is critical since they must be able to hold up to pressure in 2 directions (against the tensioner as well as the pulleys)

Test it by running it without the cover on and watch it - then stop it and feel for heat on the belt right way...... shouldn't' be overly hot


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## Sid

Does the driven pulley  turn over by hand fairly easily? Are the pulleys lined up? they cannot be out of line more than 1/16" of an inch. The idler / pressure pulleys must be inline also.
Sid


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## mzblues1

Yes, after replacing the Idle Pulley and it's parts, everything looks good. It seems to be working good as well as long as I don't pull the Auger Handle down all the way. Then it starts to smoke.

The only fix so far is to leave the belt so loose as not to have it engage the Idle Pulley too tight against the belt. Other then that, it seems o be working fine so far.


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## mzblues1

Meant leave the cable so loose


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## Grunt

Sid said:


> Does the driven pulley  turn over by hand fairly easily?




I agree with Sid. Are you sure there is no extra drag on the auger belt because of a bad bearing(s) on the auger or impeller shafts? Have you tried spinning the impeller with the belt off and check for resistance ( remove spark plug wire for safety)? The belt shouldn't smoke with tension on it unless something is amiss with the auger\impeller. Feathering the drive handle to stop the smoking is just allowing the drive belt to slip and burn into the belt. It looks like you actually have to much slack in the auger belt the way it is adjusted now.


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## skutflut

mzblues1 said:


> Honestly I don't know if the OEM's smoked or not since they were always covered before they broke. However, I have replaced at least one per year when using them.
> 
> Regarding the Kevlar Belts, it says it is, so I can only hope that they are being truthful. They actually are cheaper then OEM, so I figured it was worth the try.
> 
> Here are the images that you requested.


Is that new idler pulley the same diameter and width as the old one was? Like others have said, the drive pulley and the driven pulley must be in line with each other when running. If they are out of line, there may be a large amount of friction being generated, = heat = smoke. 

It would be safer to check this out by splitting the machine and then you can really check what goes on with the front end mechanicals.

With the spark plug disconnected, is there any back to front slop in the impeller shaft, like from the gearbox backward to the impeller pulley which the belt rides on? What about side or up/down slop in the impeller pulley at the back where the bearing hides behind the pulley. Any grinding or grating sounds if you turn the pulley manually, or is it difficult to turn? Have you checked the impeller gearbox to see if its full or oil or whatever lubricant is supposed to be in it?

Same question for the auger bushings on the ends of the bucket. Does everything run reasonably straight and true, or is there side play.


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## Sid

I just re looked at the pictures, are the belts rubbing on other parts near the pulleys ?
It might be an illusion, but it sure looks that way.
Sid


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## mzblues1

I was just thinking. 

Do you think that this might get more people who have experienced this issue to share their experiences if this was in "Snowblower Repairs and Maintenance Forum" instead of in Yard Machines Forum?


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## skutflut

Sid said:


> I just re looked at the pictures, are the belts rubbing on other parts near the pulleys ?
> It might be an illusion, but it sure looks that way.
> Sid


I looked again too, and in the Right Side Loose photos, it looks like the auger belt is riding off the side of the idler pulley too far, like running against the ridge on the edge, or even overhanging the edge of the pulley?

Also looks like the top right picture in the smoking belt sequence, that the auger belt front edge is riding too high on and seems a bit off centre on the pulley.


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## mzblues1

To answer some of the questions that you have asked:
All of the parts that I replaced were OEM from MTD (except for the belt). So yes it is the exact same size idler pulley as the original one.
I see what you are saying about the belt looking like it is very close to or slightly off the edge of the idler pulley in the photos. However, you need to realize that these photos are showing how loose the cable and belt is in order to avoid it from pushing the belt too tightly to avoid it smoking. So the belt is too loose and floppy when not engaged, so it makes it look like it is not aligned with the idler pulley. I would not normally keep it that loose if it didn't have this issue. And I think when the cable is properly tightened it will not look like it is off.

Actually if you look at the top picture on the photos "straight aligned" you can see the mark left on the idler pulley is properly centered on it.

I can adjust the cable to the proper tension and take some more photos. 

Although these pictures are with the unit together, I did have the machine separated when I put the belt on and replaced the parts, and everything seemed ok.

When I had it apart, I also greased all the parts in the machine with Marine grade grease (that I also used to fix my washer and dryer).
It was a bit stiff prior to replacing those parts and lubricating everything, but now moves freely. 
I am not sure if there is any rubbing sounds from say the auger, but I wouldn't be surprised if the auger is not bent on any part of it since my home is in a more wooded area and my driveway is gravel. So even though I have it high off the ground and on plastic slider type feet, gravel and branches have gotten caught in it at times and may have caused some damage. But I don't think it is too bad since it does still operate ok.

I didn't actually specifically try to move the auger, pulleys, etc. side to side, but I don't recall feeling anything being loose when I was working on it. But I guess I could re-check specifically to see if there is any movement. 

Too me the smoking on the belt seems to be directly related to the amount of pressure that the idler pulley puts on the belt. The harder I pull the lever, the more it smokes.
And the amount of pressure that it is putting on the belt when fully engaged is more than is necessary to get the auger to function properly. 
That is what is confusing to me.


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## Vermont007

If you've been replacing belts every year, something is wrong with the way it's assembled.

You're expected to change the oil once a year . . . . but not belts ?


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## skutflut

mzblues1 said:


> I was just thinking.
> 
> Do you think that this might get more people who have experienced this issue to share their experiences if this was in "Snowblower Repairs and Maintenance Forum" instead of in Yard Machines Forum?



That might not be a bad idea. I generally look in the NEW POSTS category, but perhaps you could PM KissaFrog and ask him to move this thread for you.

Can you also take a few photos of the bottom end of your auger cable, where it attaches to the machine. Is there a spring there, or an internal spring that applies the pulling force to the swing plate?


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## mzblues1

"perhaps you could PM KissaFrog and ask him to move this thread for you"‎

Sorry, but I am not really knowledgeable about Forum lingo.
What exactly do I need to do to move it?

Regarding the end of the cable, it is a spring attached to the top of the idle pulley's plate (see attached).
There is another spring at the bottom to pull it back (which I replaced with a new one).

Although I don't think that I really needed to, I did replace the cable about 2-3 years ago.


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## skutflut

mzblues1 said:


> "perhaps you could PM KissaFrog and ask him to move this thread for you"‎
> 
> Sorry, but I am not really knowledgeable about Forum lingo.
> What exactly do I need to do to move it?
> 
> Regarding the end of the cable, it is a spring attached to the top of the idle pulley's plate (see attached).
> There is another spring at the bottom to pull it back (which I replaced with a new one).
> 
> Although I don't think that I really needed to, I did replace the cable about 2-3 years ago.


Private message Kissafrog, who is a moderator on this forum. Ask him to move this thread to the Maintenance section. Only moderators can do that.

Those photos are a bit fuzzy, but do I see bits of rubber on the idler pulley bracket around the point where the spring hooks to the bracket? Is that open end of the loop on the spring maybe digging into the belt and causing the smoke?


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## mzblues1

No. As I mentioned I greased everything and it kind of made stuff a bit dirty.

The spring is no where near the belt as you can see from the right picture on the attached. Actually the smoke is coming from the top right side away from the idler pulley.


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## Bob Cat

At this point I'd try a longer belt maybe with a larger diameter idler depending on the next size up you get. On another note I had a Mastercraft blower once that liked to smoke belts. I found the bucket didn't mesh very well when the halves were put back together. The metal where they join was very thin and had stress cracks and it was guess work just to realign the parts. When I found the right spot I put a couple locating pins in guide the next time it was disassembled.


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## mzblues1

The 2 halves of the machine aren't damaged or cracked yet, but you did make me think to look at the 2 auger pulley halves. Maybe they are not together tight enough or just old and pitted and causing the extra friction on the belt (since that is actually where the smoke seems to be coming from). I probably should have replaced those too.

So at this point from everyone's suggestions, it is narrowing down to looking at the auger and impeller pulley, auger, and related parts for any loose parts, side to side movement or damage that could be causing it to smoke as possible suspects. I guess I'll have to take it apart again and see what's up.


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## all3939

You may have one of the 2 following issues.
a) Have seen this more then once where the belt was routed on the auger pulley wrong ie. The op dropped the belt from the pulley upon installation and has the brake on the wrong side of the belt. So now, pulling the lever for the auger tightens the belt and the brake against the pulley. This will strain the auger pulley from rotating full speed holding back speed on the belt but at the same time the output shaft on the motor knows only one speed. It will burn the belt at that point.
b) Auger housing bearing is just short of seizing and its rotating speed not able to keep up with motor speed so the motor pulley spinning faster then belt travel and burn burn....


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## DennisP

all3939 said:


> You may have one of the 2 following issues.
> a) Have seen this more then once where the belt was routed on the auger pulley wrong ie. The op dropped the belt from the pulley upon installation and has the brake on the wrong side of the belt. So now, pulling the lever for the auger tightens the belt and the brake against the pulley. This will strain the auger pulley from rotating full speed holding back speed on the belt but at the same time the output shaft on the motor knows only one speed. It will burn the belt at that point.
> b) Auger housing bearing is just short of seizing and its rotating speed not able to keep up with motor speed so the motor pulley spinning faster then belt travel and burn burn....


Both of these were exactly what I was going to say since page 1 (sorry, got into this late).

Sounds like the belt is possibly around the brake portion of the auger pulley lever, ie, on the outside of it, not the inside.

Or, as mentioned, the impeller bearing is trashed and seizes up when excess pressure is exerted on it by the auger tensioner when it is pulled tight.

Outside of those, there is nothing that would cause a belt to slip in a "too tight" configuration. You really CAN'T get it too tight since the auger control cable has a spring on the end that expands to "give" once the proper amount of pressure is obtained.


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## all3939

One other observation:
The belt being used is not the correct one, width/height/length ?? and doesn't conform to the spec.
Didn't see a belt finger on that set up when I believe it should have one. Not that its causing the issue but the way the system works is that it needs to be loose when not engaged and the finger will keep it lined up with the groove and not jump out.


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## mzblues1

"b) Auger housing bearing is just short of seizing and its rotating speed not able to keep up with motor speed so the motor pulley spinning faster then belt travel and burn burn...."

Hey, DennisP and all3939,
This is exactly why I asked this thread to be moved to the Snowblower Repairs and Maintenance Forum.

Your comments (which I didn't think about at all) is the first suggestion that makes totally sense to me, and if I were a betting man, would bet that this has to be the issue.

As I mentioned previously, my blower has come across quite a few gravel and tree branches in its day (since I have a gravel driveway basically surrounded by woods), so the idea of the auger being damaged is certainly not unreasonable. And yes, if the pulleys are at 2 different speeds, then "burn, burn, burn!".

As far as suggestion "a)" goes, I don't think that my machine is very sophisticated and actually has any kind of "brake", and just slows to a stop when disengaged. Or at least I don't know enough to see where a brake would be. 

See the manual pages attached and please point out the part number for the brake, if I actually do have one?


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## all3939

Look at figure 27 , support bracket spring bottom right corner of page, just to left of it and at the far right end of idler spring , there seems to be a small brake pad or the like against the auger pulley. Follow the outline of the auger pulley from left to right, there is where it seems to be. It should be part of the idler pulley bracket. When lever is up, brake is applied. When lever is pressed down for auger motion the bracket pivots the idler pulley into the belt and releases the brake at the same time., Your blower isn't that old and has nothing to do with sophistication. Safety is safety when they were built.
ADDED NOTE
page 22 item #3 is the bracket I'm describing


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## all3939

MTD Trot Bilt Snow Blower Auger Idler Arm | eBay
This is your bracket or very similar. Enlarge the picture in that link. One of the two pictures is clear as day. Towards the bottom where you see the 90 degree bend, that's the part that press against the belt of the auger pulley to stop the spinning.


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## mzblues1

O.K., So if I understand correctly, the brake is part of the Idler Arm Bracket (see attached)?

Also, I checked it further and didn't find any side-to-side or other unusual movement of any internal parts. But I did notice that the Impeller makes a rubbing / grinding noise when it is turned and is definitely is being held back by extra friction in one of it's related parts.

It is not hard to rotate and then easy to rotate. It is the same amount of resistance throughout the Impeller's 360-degree turn with the grinding noise throughout.

The Impeller also doesn't appear to be rubbing against the body anywhere, so I am guessing it is an internal issue.

So I have narrowed it to 2 places that I think might be the cause.

1) The Gear Worm inside the Gearbox Assembly might be damaged or broken (see attached). But the noise isn't really coming from the Gearbox Assembly area. It is coming from the Impeller area.

2) The Impeller Ball Bearing (see attached). This is where I am thinking the problem is coming from and I believe the bearing needs to be replaced.

BTW: This fits right into the theory that the "Auger housing bearing's rotating speed is not able to keep up with motor speed causing the belt to smoke"

Let me know is this makes any sense or if you think another part would more likely be the problem?


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## all3939

mzblues1 said:


> O.K., So if I understand correctly, the brake is part of the Idler Arm Bracket (see attached)?
> 
> Also, I checked it further and didn't find any side-to-side or other unusual movement of any internal parts. But I did notice that the Impeller makes a rubbing / grinding noise when it is turned and is definitely is being held back by extra friction in one of it's related parts.
> 
> It is not hard to rotate and then easy to rotate. It is the same amount of resistance throughout the Impeller's 360-degree turn with the grinding noise throughout.
> 
> The Impeller also doesn't appear to be rubbing against the body anywhere, so I am guessing it is an internal issue.
> 
> So I have narrowed it to 2 places that I think might be the cause.
> 
> 1) The Gear Worm inside the Gearbox Assembly might be damaged or broken (see attached). But the noise isn't really coming from the Gearbox Assembly area. It is coming from the Impeller area.
> 
> 2) The Impeller Ball Bearing (see attached). This is where I am thinking the problem is coming from and I believe the bearing needs to be replaced.
> 
> BTW: This fits right into the theory that the "Auger housing bearing's rotating speed is not able to keep up with motor speed causing the belt to smoke"
> 
> Let me know is this makes any sense or if you think another part would more likely be the problem?


To answer your points, this is my take.
Yes, the brake is the portion of the bracket you point out.
The bearing is most probably shot to he!! If the following isn't happening.
You may be experiencing the pressure of the brake against the auger pulley and that's the metal to metal noise you have. If in fact it is, just reroute a new belt correctly and that may end the problem.
You may have something wraped up onto the shaft between the back of the impeller and the impeller housing. In any case you need to separate the bucket off tractor (motor portion), dismount the auger pulley from the impeller shaft and then the rest comes out the front of the bucket.
I doubt the gear box is gone and causing the issue because the impeller will still spin at its given speed where as the augers would not be powered by the impeller shaft at that point. Upon reassembly make sure auger pulley lines up with motor pulley very well otherwise belt wear is immanent.


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## mzblues1

O.K. Thanks, I'll do that after I get a new bearing. 

I don't think that there is anything stuck behind the impeller, but I will find out for sure when I take it apart. 

As far as the brake is concerned, I replaced the arm and the bottom tension spring (all OEM from MTD).
Pretty sure that they are properly installed, but will check that too.


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## mzblues1

O.K. I received and replaced the Auger Impeller Bearing. The original Bearing actually wasn't that bad, but figured a new one couldn't hurt. 

The scratching sound and resistance seemed to mostly to be coming from the Auger Arm's Brake rubbing against the Pulley, which goes away when you engage the Auger and moves the Brake away from the Pulley. I realize now that originally not knowing that the Brake even existed, I didn't know that I should release it before turning the Impeller to see if there was any sound of rubbing. 

So that said, I still haven't found the solution to my original issue of the smoking Belt.

However, one other thing that I did discover when I opened it up was that all of the teeth on the India made Kevlar Auger Belt was gone.
And I haven't even run and used the machine yet since I installed the new Belt! All I did was test it a bit with the Belt smoking and now it is totally flat with no teeth. 

So obviously these belts don't last any longer and I guess I should go back to the OEM Auger Belt. Maybe the smoking is being caused by the crappy belt not able to handle it? 
But somehow I can't imagine that this could actually be the problem.

So I am not sure what else could possibly be the smoking Belt issue.

Any other ideas??


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## all3939

mzblues1 said:


> O.K. I received and replaced the Auger Impeller Bearing. The original Bearing actually wasn't that bad, but figured a new one couldn't hurt.
> 
> The scratching sound and resistance seemed to mostly to be coming from the Auger Arm's Brake rubbing against the Pulley, which goes away when you engage the Auger and moves the Brake away from the Pulley. I realize now that originally not knowing that the Brake even existed, I didn't know that I should release it before turning the Impeller to see if there was any sound of rubbing.
> 
> So that said, I still haven't found the solution to my original issue of the smoking Belt.
> 
> However, one other thing that I did discover when I opened it up was that all of the teeth on the India made Kevlar Auger Belt was gone.
> And I haven't even run and used the machine yet since I installed the new Belt! All I did was test it a bit with the Belt smoking and now it is totally flat with no teeth.
> edit:
> Just saw the picture of the new belt. Looks good. I only hope you matched up the part number to the belt spec.
> 
> So obviously these belts don't last any longer and I guess I should go back to the OEM Auger Belt. Maybe the smoking is being caused by the crappy belt not able to handle it?
> But somehow I can't imagine that this could actually be the problem.
> 
> So I am not sure what else could possibly be the smoking Belt issue.
> 
> Any other ideas??


Your belts teeth (also know as a "cogged belt") are worn off for that very reason being it was riding on the wrong side of the brake essentially stripping the teeth off as it was passing the back side of the brake. The smoking is and was cause in effect. The fact the cogged portion is missing now will only cause more slipping and burning as the belts grip is diminished. Now just put things back the right way with a new correct belt and the smoking shall disappear if all else is ok.


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## mzblues1

"worn off for that very reason being it was riding on the wrong side of the brake essentially stripping the teeth off as it was passing the back side of the brake."

When the Auger is disengaged and the brake is against the belt, the belt is not turning. Once the pulley roller is applied pressure against the belt, the brake is no longer against the belt, so it shouldn't be rubbing off anything. 
Regarding the belt being upside down, the belt was installed properly with the teeth into the V of the pulley as attached.

The belt is on the roller pulley correctly, but I will double check if the brake is on the belt correctly as well.


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## mzblues1

Problem solved. I didn't think that the belt could stay on the Pulley unless it was properly installed, but I just learned that is not the case. 

The problem is that yes the Brake was not on the outside of the Belt, and therefore burning off the Cog teeth on the inside of the belt.

Problem solved. 

Thanks all3939!


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## Vermont007

All of those Indian Kevlar Belt Manufacturers will be pleased to know they were falsely accused and are now off the hook !

Where do they do to get their reputations back ?


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