1977 B80 8 Speed

[Ed Kennell 38,196]

Here is a recent thread on a similiar problem on a  Commando 800.       If you look at the picture of the belt guard, you can see the tab that pinches the belt when the tab on the idler pulley pushes the belt down against it.         I think his problem was the belt guard was incorrectly installed with this tab above the belt causing the wear on the outside of the belt.         Your belt guard may not have this tab, but it illustrates how in some cases the idler pulley tab is used to help stop the belt movement.

.Can’t get it in gear - Transmissions and transaxles - RedSquare Wheel Horse Forum

 

 

 

[Lee1977 6,663]

On 8/18/2023 at 5:27 PM, stevasaurus said:

I disagree with Ed.  I think it is just suppose to keep the belt on the pulleys.  It has been my experience that if the guide on the tension pulley is rubbing the belt, it tends to tear into it and rip it up.    The belt guard should have the means to stop the drive belt from moving when the clutch pedal is depressed, by funneling the slack toward the drive pulley.  If your belt is not stopping when the pedal is depressed, it is because the belt guard is missing a guide.  That tab on the tension pulley just keeps the belt from leaving the pulleys.

Not on a 1977 model it's there to stop the belt. The TSC kevlar belts take a little more time to set in then the Wheel horse belts, that may be the problem. If that tab is bent on a 1977 model some PO bent it. You have to loosen the Idler to get the belt on.

I bought a 1977 C-120 new back in 1977 and had it ever since. It's the same as the 8 HP 8 speed less the lights, high back seat, I guess it didn't need the 15 amp alternator. My 1988 or 89  312-8 has the same tab on the idler pulley.

 

[Lee1977 6,663]

7 hours ago, Ed Kennell said:

Here is a recent thread on a similiar problem on a  Commando 800.       If you look at the picture of the belt guard, you can see the tab that pinches the belt when the tab on the idler pulley pushes the belt down against it.         I think his problem was the belt guard was incorrectly installed with this tab above the belt causing the wear on the outside of the belt.         Your belt guard may not have this tab, but it illustrates how in some cases the idler pulley tab is used to help stop the belt movement.

.Can’t get it in gear - Transmissions and transaxles - RedSquare Wheel Horse Forum

 

 

 

Yes you can have a real problem with cheap belts being destroyed by that tab. Where some a few years back where the top of the belt was not molded into the rubber and got all chewed up.

[Racinbob 11,082]

I never really put much thought into it but I always assumed the tab thingy on the idler pulley was just for keeping the belt in place. Otherwise you wouldn't hear "ya gotta have the belt guard on to stop the belt' so often. My 76 (bought new and original) has the upper and lower tabs on the front of the belt guard and I make sure they are adjusted properly. Without the belt guard the belt won't stop even though it has the idler pulley tab. My 854 was missing the idler pulley tab and more than once I released the clutch only to have the belt miss the idler pulley. It seems like it would be easy to put the belt back on but when it happens the belt would get pinched requiring the guard to be removed. 

I can't get to the pulleys to accurately measure them without removing parts. Maybe somebody can chime in with the correct sizes. That almost has to be the issue. The idler pulley size really doesn't matter (within reason). It will tension the belt just so far whether it's 2" or 10".

I just checked the parts manual on the 854. It doesn't even show a tab on the idler pulley. 

Edited August 20, 2023 by Racinbob

[squonk 41,136]

I got no dogs in the hunt but IMHO the tab was to keep the belt from flopping off the idler. Especially when the belt was worn some. If it happens to be bent enough to pinch the belt and is helping stop the belt so be it but I don't think it was designed originally as a "Belt Brake."  

[953 nut 55,279]

1 hour ago, squonk said:

IMHO the tab was to keep the belt from flopping off the idler.

I've got to agree with Mike, If the tab wasn't there the belt would probably not stay on the idler when the clutch is depressed. Though it touches the top of the belt it will not pinch it to prevent belt movement.

 

[Handy Don 12,232]

Gotta agree here that THIS tab is dual function--keep the belt on the idler and help stop it after clutch disengages! It isn’t enough friction to stop the belt by itself so one also needs the friction from the belt cover bottom flange and the “other" tab at the engine end of the belt guard. And yes, having this means the idler/tensioner pulley has to be off to install a new belt.

Note that this tab’s edges are bent upward to keep them from hitting the belt.

[Ed Kennell 38,196]

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Does this picture help explain how Wheel Horse was using the forward/downward rotation of the idler pulley and its belt retainer tab to pinch the belt against this fixed tab to insure the belt is not moving during declutching?

  You can see the location of the idler and transmission drive  pulleys on the belt guard.

[Lane Ranger 10,968]

New belts vs old belts do operate with a lot of variation.  When you depress the clutch to change gears on an old belt it can grind gears due to slip in the belt.  The   Belt retainers in various Wheel Horse models were somewhat different as well as the belt guards.  I believe the Wheel Horse developers put the belt retainers on to keep the belt from flying off the idler pulley.  But I also know the belt retainers can be adjusted to either tighten or loosen the amount of retention of the belt as needed.  
 

On the RJ sickle attachment a belt guide is used on the outside of the motor and the drive belt is retained on the pulley when the sickle is in clutched or disengaged.  

[Ed Kennell 38,196]

2 minutes ago, Lane Ranger said:

 I believe the Wheel Horse developers put the belt retainers on to keep the belt from flying off the idler pulley

No question there Lane.     As you know and anyone that has used a belt/v pulley as a clutch knows there must be belt retainers to keep the slack belts in place as there must be a means of supporting the bottom of a slack horizontal belt.      

The question is does the idler pulley and it's belt retainers contact with the slack belt help to ensure the belt is not rotating.

IMO, it does help and some of the WH engineers must have put the belt stopping tab on some belt guards to add additional friction to aid in stopping the slack belt.

A caution to owners that have this tab on thier belt guard.  I have seen several where the belt guard was incorrectly installed with the belt below this tab.   Unfortunately, the belts are instantly destroyed.