I have a 2013 TB Pony 42” lawn tractor that I got for free but without the mower deck. I acquired a 42” deck for a TB Bronco. Is it possible to install the Bronco mower deck to the Pony? There are a few differences I noticed:

1. Mower deck drive belt is longer as it sticks past the drive pulley by at least 3”. Come to find out the Bronco uses a 99” belt and the Pony uses a 96.5” belt.
2. The height adjustment rod nut for the Bronco has to be threaded all the way just so the beveled washer sits in the attachment bracket. However, when I lower the deck, the adjustment rod is loose and has play. Is this normal?

Any help is greatly appreciated.

Louie

Sounds like you may have to shorten that front adjuster rod. 
 
Weather cut and re-weld, or bend / modify.
 
You adapting two different machine parts together, so some engineering is likely.
 
If you have access to "Tractor Supply", they have many deck belts,
in 1" increments that should help in getting the exact size you need
(return the ones that don't fit)...
 
 

Would using a die to cut more threads on the shaft be another option other than cutting and welding back together to shorten the length of the adjuster rod?

Sure, that'd work..
 
**For testing purposes ONLY, cut some .5" PVC PIPE, (approx 1-3").
Slip it over that threaded rod BETWEEN the adjusting nut and the frame.
That'd mimic a shorter rod/more threads on your current rod and see how 
that mod works.
 
 
 
 
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Now why didn’t I think of that? 🤦‍♂️

Here’s a photo of the new mower deck belt that I purchased and installed for a Pony model deck but of course this is a Bronco deck. Would you say it’s too long? Turns out the original belt and the new belt are the same length. The belt length is 96.5 as per the part details. It’s still a 2-3 inches too long.

There's no pictures posted..
 
I just had a customers rider in for repair, also a 42" two blade.
Besides the running issue, he said the "blades didn't work well".
 
Further inspection showed the belt 3-4" TOO LONG (same as yours).
Ordered a new belt, same size.  Double checked another site, it should be the correct belt
but was again too long.
 
I pulled the belt tensioner about half way tight, then ran a wire (rope would be better)
where the belt routed and marked the length needed. 
Made a trip to "Tractor Supply", where they have a measuring device and numerous belts.. 
I believe it was a 91" I ended up using and returning the rest. 
 
As I re-call, the machine called for a 95" (or so) belt..   
 
So what that issue was about, dunno.  The deck DID belong to the machine but this belt fixed the issue.
 
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