Wheel nuts, don't look right???

[Fromjim]

I just bought a new M 108X Kubota tractor, this is a very nice tractor but I noticed something unusual, the rear wheels have cast centers and as I examined them I noticed that the wheel nuts in the center of the hub seem to be installed backwards, the nut has a thick washer next to the cast hub and the flat part of the nut is against the washer with the sloped side of the nut facing out, the opposite of what you would expect, also I see that the studs do not extend past the nut, that is the stud is about 2 or 3 threads from the end of the nut, usually there are a few threads outside the nut.

Does anyone have access to the specs. for these nuts/studs, I noticed the part number of the studs in my parts book is different depending on the type of wheels you have, steel vs cast centers.

I live a long way from my dealer and don't want bother him if this is OK, but I have had tractors for over 20 years and have never seen this before.

I would appreciate your input before I contact my dealer.

Thanks
Jim

 

[PILOON]

For max holding the flat side would want to be against a flat face on normal hardware.
but as you note wheel nuts are generally curve to curve fitted with the nut being a different radius than the rim radius for a jamb fit.

Sound to me like they lost the nuts and replaced with standard ones and added the washers so as to not deform the curved 'sockets' in the wheel.
Could be simply that they borrowed them from that tractor to sell as spares and simply forgot to re install.

A standard used is that there should always be 1 1/2 to 2 1/2 complete threads showing on a stud/bolt.

I think you are correct, but check your parts book to be sure.

 

[Fromjim]

For max holding the flat side would want to be against a flat face on normal hardware.
but as you note wheel nuts are generally curve to curve fitted with the nut being a different radius than the rim radius for a jamb fit.

Sound to me like they lost the nuts and replaced with standard ones and added the washers so as to not deform the curved 'sockets' in the wheel.
Could be simply that they borrowed them from that tractor to sell as spares and simply forgot to re install.

A standard used is that there should always be 1 1/2 to 2 1/2 complete threads showing on a stud/bolt.

I think you are correct, but check your parts book to be sure.

Hi, thanks for your input, the nuts are curved but the curve is on the outside rather than out of sight as you would expect, I believe that if the washer was removed, it is about 1/8" thick, and if the cast wheel center has a depressiion then the threads would probably extend past the nut. I am not using the tractor much and I know that the left wheel was removed to have a creeper kit installed when I bought the tractor, the nuts are the same on both sides, the mechanic who worked on my tractor has many years experience and I have confidence in him so I'll wait until I can talk with him or look at other tractors to verify this setup. I may remove one nut to verify if the cast is curved to accept a curved side of a nut.

Tell me what you think.

Thanks

Jim

 

[PILOON]

Sounds like a plan.

Good luck!

 

[Fromjim]

Hi, thanks for your input, the nuts are curved but the curve is on the outside rather than out of sight as you would expect, I believe that if the washer was removed, it is about 1/8" thick, and if the cast wheel center has a depressiion then the threads would probably extend past the nut. I am not using the tractor much and I know that the left wheel was removed to have a creeper kit installed when I bought the tractor, the nuts are the same on both sides, the mechanic who worked on my tractor has many years experience and I have confidence in him so I'll wait until I can talk with him or look at other tractors to verify this setup. I may remove one nut to verify if the cast is curved to accept a curved side of a nut.

Tell me what you think.

Thanks

Jim

I just looked again at my parts book, thanks to you, and think I see what happened, in the parts book the wheel with cast centers has a washer, they call it a spring plate, the nut shown is flat on both sides and the number of the nut is, 36200-4913-0, when I look at the wheel with steel centers I see a nut like what I have, tapered on one side and no washer, the number is 33251-4917-0, I believe for some reason the tapered nut was used instead on my tractor and since the tapered nut is longer (by the length of the taper) then the nut would excede the stud by this excess, but the total number of threads on the stud would actually be more than on a nut with two flat sides.

Please comment.

Jim

 

[PILOON]

OK, I understand what is going on.
Stud nuts usually have about twice the 'grip' as a regular nut for the same size of thread.
The wheels you have seem to be optional models.
In fact then the nuts being reversed are doing the job just fine as they are used with the reguired spring plates.
It then is just esthetics.

In fact more than likely the stud nuts would be a higher grade nut than a regular nut, just have more thread to grip but not all used as the stud is too short.

Sounds just fine to me.
UNLESS they were supposed to install longer studs?
Can you check book for that ?

 

[Fromjim]

OK, I understand what is going on.
Stud nuts usually have about twice the 'grip' as a regular nut for the same size of thread.
The wheels you have seem to be optional models.
In fact then the nuts being reversed are doing the job just fine as they are used with the reguired spring plates.
It then is just esthetics.

In fact more than likely the stud nuts would be a higher grade nut than a regular nut, just have more thread to grip but not all used as the stud is too short.

Sounds just fine to me.
UNLESS they were supposed to install longer studs?
Can you check book for that ?

I checked my parts book, and there are two lengths of studs listed, I would have to have the right studs since the cast centers are about 2" thick and the steel center studs would only have to be about 1.25" long, I think I am safe, I asked for wheel weights afte ordering the tractor, I didn't know anything about cast centers, I thought wheel weights were added to steel wheels, but Kubota must offer cast centers as an option and my dealer probably thought about the studs being shorter on the steel version and ordered the long studs when he ordered the cast centers or he may have just taken the cast centers off another tractor and changed the studs on mine not thinking about the nuts being different or it could be they wanted extra strength in the nuts so they used the tapered ones knowing more thread would be on the studs, I'll ask them next time I go down to see them.

Jim