641 Rear Rim Question

[Arroyo]

My tractor has been missing a rear hub to rim bolt since I got it about 6 months ago. I finally ordered one, but when I received it, it wouldn't fit. After looking at the rims on both sides which are the 6 loop type, I noticed that on one side the carriage bolts have a large head and the loops have a square opening for the square section of the bolt to fit, the bolts have a coarse thread. The other side uses a smaller head carriage bolt and the loop openings are basically round. This side uses a fine thread bolt and a smaller nut . One of the rims has been swapped out at some time, does anyone know which is correct? I can probably find a used rim pretty easily and I'm looking to get new rear tires in the next year so I may try to trade one of the rims so that they match.

 

[showcrop]

I can't tell yu for sure but from the Fords that I have/have had, I am pretty sure that round and coarse would be early and square fine would be later.

 

[WayneIA]

They came from he factory as 5/8 carriage bolts and a nut that used a 1 1/16 wrench