# Drive Problem - Overengaging



## vuldub (Feb 3, 2020)

Hello. I have a Troybilt 31BM53Q2563. I bought it used, but it had only been run a couple of times. There is a problem with the drive that I cannot troubleshoot. I understand how the drive cable works and engages the wheels. So I am using the correct terms: the hand lever pulls a cable that hinges up a metal friction disk to contact with the rubber rimmed friction wheel that is attached to the wheel axle. 

Here are the symptoms with my machine. When you pull the lever to engage the drive cable, as the friction wheel starts to make contact lightly, the snowblower advances. However the lever still has travel left and as you continue to pull the lever to the full "on" position, the friction disk presses so firmly into the friction wheel that the drive stops. The problem is that the cable adjustment is at the very end limit of loosening and when the lever is not engaged, the cable has considerable slack but I cannot make it with more slack as there is no more adjustment. I experimented with moving the cable end at the lever into the second hole (there are two holes in the lever - not sure why - probably for multiple applications). No change. I have no reason to believe that any parts have been changed on this machine - perhaps is was assembled wrong at Canadian Tire where the PO bought it. It would seem to me that the engagement is not overly firm - from point of contact to full on the cable only moves 1/2", yet its enough to bind the drive. The friction wheel looks to be in great shape as do all the belts. Also, there is no slippage on the belt, when fully engaged, the metal fiction plate stops turning. Thoughts?


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## oneboltshort (Dec 16, 2019)

vuldub said:


> Also, there is no slippage on the belt, when fully engaged, the metal fiction plate stops turning. Thoughts?


 If this is true, the drive sheave on the crank may have lost it's key. If the friction plate/platter (the one with the belt from the engine hooked to it) stops, either the belt is slipping or the belt is not being driven.
In other words the belt has to be stopping or slipping as the plate is hooked directly to the belt. If your idler has lost it's tensioner spring, you may get this condition. There may be enough residual friction to appear the belt is running and not slipping until the plate stops under full engagement.


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## vuldub (Feb 3, 2020)

oneboltshort said:


> If this is true, the drive sheave on the crank may have lost it's key. If the friction plate/platter (the one with the belt from the engine hooked to it) stops, either the belt is slipping or the belt is not being driven.
> In other words the belt has to be stopping or slipping as the plate is hooked directly to the belt. If your idler has lost it's tensioner spring, you may get this condition. There may be enough residual friction to appear the belt is running and not slipping until the plate stops under full engagement.


I think I understand what you are saying, that the driveshaft out of the engine cannot stop turning (or the engine would stall). So there must be slippage somewhere to accommodate this direct output. I can tell you that the friction plate stops completely. I have observed the belt from the front and it does not appear to be slipping but I will recheck it. I was thinking the idler tension spring might not be installed properly, but cannot find a picture of its correct installation.

If the drive sheath on the crank has lost its key, then it would not work at all, correct? As I mentioned it works fine with light engagement, half depressing the drive hand lever. Fully depressing the drive hand lever appears to cause it to bind and not propel the friction wheel. And there's no room to back off the tension, its at the end of adjustment and the cable is very slack, which seems too slack. There's no reason for this to be at the end of tension adjustment since there are only 20 hours max on this machine.


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## oneboltshort (Dec 16, 2019)

If your drive idler tension is not full, the belt will still run under some friction, but as you apply more pressure from the friction wheel it takes on the weight of the machine and the plate can stop, but the belt may appear to going, yet slipping.
Watch this video to see if your tension spring is on first.
If your drive sheave (there are 2 halves to it) lost a key, it would still turn enough from it's fit and residual friction, but lose traction once the load of the friction wheel is engaged (whole weight of machine and terrain you're on).


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## vuldub (Feb 3, 2020)

oneboltshort said:


> If your drive idler tension is not full, the belt will still run under some friction, but as you apply more pressure from the friction wheel it takes on the weight of the machine and the plate can stop, but the belt may appear to going, yet slipping.
> Watch this video to see if your tension spring is on first.
> If your drive sheave (there are 2 halves to it) lost a key, it would still turn enough from it's fit and residual friction, but lose traction once the load of the friction wheel is engaged (whole weight of machine and terrain you're on).


Thanks for the video. That looks very similar to my issue. I will expand the tensioner spring as the video author suggested (is that you?). 

Since it will pull uphill and pull when under load (with a partially engaged drive lever) I am thinking the drive sheath key should be ok. Also, once it has been operating, it isnt as finicky about the partial engagement, but sometimes is stops under load and I have to push it to get it going. That might be the difference between a cold belt and a warm one. Is dressing the belt with a sticky belt dressing spray a bad idea? 

As I am familiar with other mechanical things (I rebuild old motorcycles and old jeeps) I was suspicious about the belt tensioner - in fact I am suspicious it is not pivoting properly as it is all mucky when everything else is spotlessly clean. I will yank that tensioner out tonight and clean it up. Thanks again.


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## penna stogey (Nov 25, 2019)

Welcome to the SBF from Gettysburg....Throwing out that first welcome mat!!


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## vuldub (Feb 3, 2020)

oneboltshort said:


> If your drive idler tension is not full, the belt will still run under some friction, but as you apply more pressure from the friction wheel it takes on the weight of the machine and the plate can stop, but the belt may appear to going, yet slipping.
> Watch this video to see if your tension spring is on first.


Well oneboltshort, you nailed it. The tensioner spring was lazy as the video highlights. I took it off, encouraged it to be stronger, reassembled and voila the machine now pulls me across the yard. Thanks!


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## vuldub (Feb 3, 2020)

penna stogey said:


> Welcome to the SBF from Gettysburg....Throwing out that first welcome mat!!


Howdy from the great white north (Alberta). I hate to dine and dash, but oneboltshort nailed the solution, so my blower drives fine now. It's a pretty new machine, so you won't likely see me back here for a while. I have an old GMC truck to encourage back to life...


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## vuldub (Feb 3, 2020)

Update. Fix worked great. Machine drags me around the yard now. Fun to operate.


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## RAOUL225 (Jan 24, 2020)

vuldub said:


> Well oneboltshort, you nailed it. The tensioner spring was lazy as the video highlights. I took it off, encouraged it to be stronger, reassembled and voila the machine now pulls me across the yard. Thanks!


Order a new spring because they have a tendency to break where they hook at each ends.You don't want to push the machine the rest of the season


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