1863 with 48"GT deck. Belt too long
 

The belt on my 1863 with 317-48" deck broke. I ordered a 5/8 x 92" replacement belt but it is to long. I measured the old belt this morning at 88". I took the old belt to my cub dealer this morning and he said the 5/8x92 belt is what it calls for. The 88" belt has been on it since I got the tractor and has worked OK. Something must be screwed up about the deck attachment but I have no idea what. Picture of the mule drive pulleys almost rubbing with the 92 inch belt installed.
Cannon

Don't know what happened to the picture.
Cannon

According to the Cub Cadet parts look-up site, it calls for a 954-3001 Belt, which is a Section B x 91.68" long (or 5/8" x 92").

A better picture of the Mule Drive Assembly would be most helpful.

I made some more pictures but it's so humid here the lens kept fogging up. I don't have a lot of room between the back of the deck and the wheels, maybe 2 inches. I figure I would need to go back at least an inch to get close to the belt adjustment notches. I was hoping this was a common problem. Does anything affect the front and rear position of the deck other than the hanger to mule drive attachment point?
Cannon

I was hoping for a better shot (or wider angle) of the top picture. I suspect the arms to the Mule Drive maybe mounted in the wrong spot.

I believe this is the hole the 317 owners manual shows.
Cannon

Perhaps mounting the arms in this location....

With the proper mounting and belts, you should end up with the Mule Drive Pulley alignment like this........Belt Alignment

If the 88" belt worked fine for a long time, I probably wouldn't worry about having the "right" belt.

That said, my 48" mower mounts in the same holes as the OP's and the belt fits fine. I believe you could move the deck back to the aft holes on the carriage with a 48" deck. No way on a 54".

(A) There is something obviously wrong.

(B) The pictures presented, do not reveal the whole condition or situation.

So, we can only speculate as to what is the problem.:Unknown: