Mule drive differnce?!!!

[DukeRooster 2]

Ok so I have a 520 H Onan 20 hp 275 hours, with a 38 inch deck. I just Bought a nice 60 inch Deck from a local guy. The Mule drive belt on the 60 inch deck broke so i swaped the mule and belt from the origional 38 inch deck as a quick fix and it seems to work fine with the 60 inch deck. The only thing ive noticed is some blade speed reduction in thicker grass but overall i think its working propperly. Ive read the mule drives are differnt. Am i missing something? Also this is the 1st time ive used a mower on my 520H the PTO belt goes on the rear groove of the pto pulley not the front groove correct?   I guess my real question is all factors above will any of this effect the blade power or speed in tall grass. Ive manage to mow about 10 hrs and 4 acres twice since i installed the 60 inch deck with the mule from the smaller deck. Overall beautiful cut but seems to slip and blade speed reduction thicker areas. 

Edited May 5 by DukeRooster

[Wayne0 465]

First off, to Red Square.

My two tractors, a 1987 Work Horse and 1992 520H have the same mule.

The belt to the mule/deck goes in the OUTSIDE groove on the pulley. Inside is bigger and will give you slower belt speed.

[gwest_ca-(File Mod) 11,050]

Here is the idler assembly for the 60" deck

https://www.partstree.com/models/78390-toro-60-side-discharge-mower-deck-sn-059000001-059999999-1995/drive-attachment-3/

 

[lynnmor 7,309]

24 minutes ago, Wayne0 said:

First off, to Red Square.

My two tractors, a 1987 Work Horse and 1992 520H have the same mule.

The belt to the mule/deck goes in the OUTSIDE groove on the pulley. Inside is bigger and will give you slower belt speed.

Just the opposite, the belt goes on the larger pulley for a faster blade speed.  The correct mule drive has spring loaded pulleys to compensate for the change in location as the deck height is adjusted.  Running a fixed location mule drive may lead to the belt being too loose or too tight.

[peter lena 8,639]

@DukeRooster  every deck set up is different , basically it comes down to , collective drag  on that drive set up , going from a 38 to a 60 , in deck is like freewheeling   and then  dragging a lead sled , lots of  rotational / function  is the issue , can you move the PTO drive belt  by hand easily on the 60 "?  cutting at highest setting ? sounds like it might be a discharge issue , how is the deck underside grass build up ?  pete

 

[Rick3478 428]

The standard mule will fit with the 60" deck, but belt angles may be less than optimum, and you may be shortening the life of the belt.  The usual mule used on the 60" deck has the outer idler offset a bit to feed the larger deck pulley more direct.  Mowers usually drive from the large inner PTO sheave for maximum blade speed.

[Ed Kennell 38,241]

Inner pulley on the PTO for faster blade speed.     The mule drive has no effect on the blade RPM.    The correct mule drive for the 60"deck has spring loaded constant tension pulleys.

[Ed Kennell 38,241]

2 hours ago, Wayne0 said:

Inside is bigger and will give you slower belt speed.

Sorry Wayne, but just the opposite is true.      larger driving pulley (PTO) increases belt speed and smaller driven pulley (deck) increases blade RPM.

Edited May 5 by Ed Kennell

[Ed Kennell 38,241]

 to the   Duke

3 hours ago, DukeRooster said:

seems to slip and blade speed reduction thicker areas. 

 

I don't have the special spring loaded mule drive required for your 60" deck, but you could place an ad in our wanted section, or call Lincoln at Ato Z tractor to purchase a used one.

 

In the mean time, remove the deck belt guards and clean the spindle belt tensioning pulley, spring, and slide bar.   It could be only  the two outside blades are slowing in the thick grass.

Also check the tension on the PTO belt.  You should only see about 1/2" deflection with slight pressure midway between the PTO and mule drive.

Do replace it with the correct mule drive ASAP.

[Brockport Bill 1,668]

10 hours ago, DukeRooster said:

Ok so I have a 520 H Onan 20 hp 275 hours, with a 38 inch deck. I just Bought a nice 60 inch Deck from a local guy. The Mule drive belt on the 60 inch deck broke so i swaped the mule and belt from the origional 38 inch deck as a quick fix and it seems to work fine with the 60 inch deck. The only thing ive noticed is some blade speed reduction in thicker grass but overall i think its working propperly. Ive read the mule drives are differnt. Am i missing something? Also this is the 1st time ive used a mower on my 520H the PTO belt goes on the rear groove of the pto pulley not the front groove correct?   I guess my real question is all factors above will any of this effect the blade power or speed in tall grass. Ive manage to mow about 10 hrs and 4 acres twice since i installed the 60 inch deck with the mule from the smaller deck. Overall beautiful cut but seems to slip and blade speed reduction thicker areas. 

I have an offset mule for 60 inch mower decks - I am not using if you need one?

[kpinnc 12,111]

I've used a "standard" mule drive with the 60 deck and never had issues. 

 

That being said, the offset spring loaded mule drive does clear the swept axle and pulley better. 

 

So if you use a brand new drive belt for the deck with the standard mule drive, the pulleys run close enough to the axle to make contact when the axle pivots. 

[Ed Kennell 38,241]

5 hours ago, kpinnc said:

 

So if you use a brand new drive belt for the deck with the standard mule drive, the pulleys run close enough to the axle

Would a 1" longer belt move the mule forward enough to increase the clearance?

[peter lena 8,639]

@DukeRooster also make sure any spring tension / movement point , is lubricated , no rusty scale , or possible hang ups . pete

[Wayne0 465]

19 hours ago, Ed Kennell said:

Sorry Wayne, but just the opposite is true.      larger driving pulley (PTO) increases belt speed and smaller driven pulley (deck) increases blade RPM.

Mine both came that way to me (used). I guess the PO changed it. I will definitely switch then back to where they belong. Ya learn something new every day!

[Ed Kennell 38,241]

2 hours ago, Wayne0 said:

Ya learn something new every day!

Same here, problem is trying to remember what I learn.

[kpinnc 12,111]

4 hours ago, Ed Kennell said:

Would a 1" longer belt move the mule forward enough to increase the clearance?

 

That seems reasonable. I only mentioned a "new" belt since they haven't stretched any.

 

The issue that I'd be concerned with would be is you have enough adjustment for a "1-inch oversized" belt once it has stretched.

 

 

[Wayne0 465]

On 5/6/2024 at 11:42 AM, Ed Kennell said:

Same here, problem is trying to remember what I learn.

Thanks for that info, Ed! I swapped the belt and the deck kicks a$$ with the new wide blades! Small saplings don't stand a chance.

[DukeRooster 2]

ok So i am going to put the correct drive back on mainly because of the belt slippage. But i dont have a belt for that drive. I tried to use the belt for the standard drive abd its definatly too tight even on zero of tge tension handle. Lookibg to schematic posted above looks like i need the 113072 is this correct and does anyone have a crossover number for this belt?

[peter lena 8,639]

@DukeRooster  not familiar  with your exact set up , but  typically any part of the belt driven , attachments  has a problem of function , helping to drag down the entire belt drive function . that spring pulley assist , and correct belt set up combo , is more than enough to drag everything down . agree with others on approach to problem , my approach is to detail , rotational function , bearings , spring slide / movement point . pete 

[Jon Paulsen 290]

On 5/10/2024 at 2:23 PM, Wayne0 said:

Thanks for that info, Ed! I swapped the belt and the deck kicks a$$ with the new wide blades! Small saplings don't stand a chance.

What kind of blades are these you have, @Wayne0 ?

[Wayne0 465]

14 hours ago, Jon Paulsen said:

What kind of blades are these you have, @Wayne0 ?

Part # 14-4879. When I look them up, they come in 2 widths from different vendors. 2-1/4" and 2-1/2". I'm running the wider blade. More steel = more mass.