Question for the Narrow Frame Experts

[dkirk]

I'm presently rebuilding the mower deck linkage on my son's 107 Cub. The spring loaded idler arm bracket is so worn (holes elongated) that the belt jumps. My question is does the angle of the idler pulley (shown to the right in the picture) look correct? I want to get this angle correct before spending lots of time in the rebuild process.

 

[kmcconaughey]

David, there should not be much if any angle to the idler on the narrow frame mule drive. If anything, it should angle the other way just slightly. I'll see if I can dig up a good photo for you.

 

[digger]

I'm presently rebuilding the mower deck linkage on my son's 107 Cub. The spring loaded idler arm bracket is so worn (holes elongated) that the belt jumps. My question is does the angle of the idler pulley (shown to the right in the picture) look correct? I want to get this angle correct before spending lots of time in the rebuild process.

 

[kmcconaughey]

Here's a photo of the one on my 127. This one is worn a bit and is angled too much, you can see how the belt is pulling it towards the outside of the tractor.

 

[dkirk]

Kraig and Charlie, thank you very much for the photos and descriptions...much appreciated. I'll post a picture and details of the repair when completed.

 

[Neil Mullins]

My 106 developed belt jumping & it all boiled down to a worn mule drive. I had to replace the main 1/2” cross pin that the pulley brackets anchor/hinge on. Also had to weld up the holes in the idler pulley brackets & re-drill to fit new hinge pin.

 

[HKCooper44]

If you have an excessive angle between a pulley and a belt, the pulley can either grab the belt and throw it off, or rapidly wear one side of the belt, ruining it. Same applies to deck pullies and belts. For this mule drive, I'd replace both pullies and the pully shaft!

 

[jack casey]

I'm presently rebuilding the mower deck linkage on my son's 107 Cub. The spring loaded idler arm bracket is so worn (holes elongated) that the belt jumps. My question is does the angle of the idler pulley (shown to the right in the picture) look correct? I want to get this angle correct before spending lots of time in the rebuild process.

Geez, the first 9 on ebay are like yours. On for $49.99 may be ok.
Good luck,Jack

 

[dschwandt]

What part is it exactly you are needing?
How about a picture?
I have several NF drives laying around

 

[dkirk]

David Schwandt - thank you for the offer to help. I think I can salvage the idler arm bracket that I have with a bit of welding and straightening. If this doesn't work out, I will be in contact to purchase a bracket from you.

 

[dsarow]

With the belt off,does the pulleys align more in a straight line as they must be the intermediate guide from the pto hub to the center hub,which are different diameters. I'm going to inspect mine just to prevent a problem.Down time and chasing parts is never fun.Good luck

 

[jack casey]

Geez, the first 9 on ebay are like yours. One for $49.99 may be ok.
When I got my CC102 the mower needed some attention. After a bit of rust treatment and epoxy painting I re-installed the mower and figured out how to remove blades for sharpening w/o taking mower off tractor. With mower back on the belts kept popping off so I spent lots of time with the IH manuals. Became well acquainted with the mule drive, saw the idler pulleys as well-designed and working properly, but saw that I made a mistake with the belt install. The pulleys shown by David and even Kraig need be replaced. Cheers, Jack

 

[MadMonkMort]

I had/have a similar problem with my mule drive. The pulleys on mine are both tensioned with a threaded rod and nut, no spring. I tried swapping out the one that's supposed to be spring tensioned, but that actually made the belt jump problem worse. I also believe my current belt is too long (84") and that scaling back to an 82" belt when the 84" finally gives out will help the situation. I think that time may be near, as the belt jumped on the mow before last, and when I popped it back on, I basically have no more slack to take out of the belt with my mule drive pulleys. I have noticed also that the belt to pulley angle on the uptake side of the drive PTO pulley has to be pretty square, or the belt jumps off more frequently, meaning the mule drive departure pulley has to do more of the slack uptake work, making the belt departure angle from the PTO drive pulley more extreme, probably accelerating belt wear.
I will say I think my mule drive pulleys are in better shape angle-wise than yours are, but my current belt situation is probably not helping anything.

It may be way more problematic than my old plug-in electric push mower, not do quite as thorough of a job (I have a lot of obstacles that create areas my 104 just can't get to), but gawd I love mowing with my Cub... it's like having a little go-kart ride AND getting a chore done at the same time, in style!

 

[MadMonkMort]

Some pix to show what I was talking about on mine. My belt is so worn that even on the uptake side of the drive PTO it's kicked slightly forward because I just don't have any more thread to suck up the slack on the left hand side (normally the sprung side) of the mule drive pulleys. Did I read somewhere else that the correct length for this belt is 77"? Wow did I guesstimate wrong when bought this one...

 

[mgonitzke]

What model tractor is that? That PTO clutch isn't original, so who knows if the OEM belt length will even work.

Those blue kevlar belts are awful...they probably stretch about 2" in this application after initial run-in, and they don't last. You really need to get a spring to replace that second tensioner bolt. That's not helping anything either.

 

[MadMonkMort]

What model tractor is that? That PTO clutch isn't original, so who knows if the OEM belt length will even work.

Those blue kevlar belts are awful...they probably stretch about 2" in this application after initial run-in, and they don't last. You really need to get a spring to replace that second tensioner bolt. That's not helping anything either.

It's a 104, but the clutch is an electric model. I agree, I'm not the hugest fan of it, as it's either all or nothing, but it's what I have, and I'm not spending any more money on it right now, because it DOES work. I've also learned how to make the twin screw mule tensioner work for me, and it's not bad. It probably does stretch the belt a bit prematurely, but apart from my starting with a belt that's too long, it really hasn't seemed to hurt anything, and putting the spring in there on the one side actually made the skipping off worse. And numerous folks have said the blue belts are bad, and exactly zero of those people have volunteered their opinion on which belts they think are better, so I'm open to hearing what brand you think my next belt purchase should be, and I'll give it a whirl.

 

[dschwandt]

OK, so you have an electric clutch on your Cub, correct?
What is the diameter of the clutch and the width of the sheave on it?
Compare this with the diameter of the clutch that is supposed to be on there.
Therein may lie the gist of your issues with the mule drive pullies not lining up and the belt issues you are having.

Must not be the original engine either, any clue as to what engine it is? an AQS perhaps?
I think you should start a new thread for your issues so more folks can zero in and try to help.
May we assume you bought tis unit in its present configuration thereby inheriting all it's issues in the process?

 

[mgonitzke]

OEM
Gates Power-rated (black with red label)
Non-blue lawn and garden Kevlar belts

You will be spending more money on it in the form of belts if you don't put the correct spring on there as the factory intended. When that electric clutch engages, the belt will momentarily have to stretch a LOT with no tensioner spring, and the belt tension will most likely always be too low after the belt heats up. The whole point of the spring is to maintain proper tension under a variety of conditions.

The "skipping off" is because the belt is too loose or you are using a spring that is not stiff enough.

And as David has alluded to, the clutch pulley looks bigger than the original one, so all of the geometry of the entire belt run is probably off. It will probably be cheaper in the long run to put it back to OEM.

 

[jack casey]

I said, above, that Kraig's pulleys need replacement. Taking another look I got that wrong, see other posts about belts and pto.
Jack

 

[dsarow]

I'm a big fan of O.E.M.