mystery bolt

[metalbender]

The wear on the threads indicates movement for a while. time ro get dirty, crawl under and look for loose attachment points of a bracket of some kind. The length would rule out some lots of small stuff. I'm thinking a major component.

 

[aczlan]

It looks to me like it's either a lug nut or one of the bolts used to secure something such as the loader frame or a backhoe subframe (if you have a backhoe).
It could possibly also be one of the bolts use to attach the bellhousing to the back of the engine, but usually those would be painted the same color as the engine and transmission.
The bolts for the loader, backhoe or the wheel lug nuts would all be shiny like that if your L series is like our L3830.

Aaron Z

 

[ptsg]

It looks to me like it's either a lug nut or one of the bolts used to secure something such as the loader frame or a backhoe subframe (if you have a backhoe).
It could possibly also be one of the bolts use to attach the bellhousing to the back of the engine, but usually those would be painted the same color as the engine and transmission.
The bolts for the loader, backhoe or the wheel lug nuts would all be shiny like that if your L series is like our L3830.

Aaron Z

True and Kubota does like to use fine threaded hardware to attach frames to their castings.

 

[Big Barn]

Fine thread metric always screams ALIEN to me...

 

[metalbender]

Wheel bolts don't usually have lock washers.

 

[aczlan]

Wheel bolts don't usually have lock washers.

They do on Kubota's, the ones on the back of our L3830 all have lock washers.
There are flat bolt just like that with lock washers, not a bolt with a seat like you would expect to see on a car wheel bolt.
Thinking, the other place that I have seen bolts like that is attaching the grill guard in the front, but the head on those appears larger in relation to the diameter of the bolt.

Aaron Z

 

[jmc]

They do on Kubota's, the ones on the back of our L3830 all have lock washers.
There are flat bolt just like that with lock washers, not a bolt with a seat like you would expect to see on a car wheel bolt.
Thinking, the other place that I have seen bolts like that is attaching the grill guard in the front, but the head on those appears larger in relation to the diameter of the bolt.

Aaron Z

That's exactly the way I remember the rear bolts on my L4330.

The 360 deg of circumferential thread wear under the head seems rotation is involved in whatever it was holding- like a wheel.

 

[sea2summit]

True and Kubota does like to use fine threaded hardware to attach frames to their castings.

If the scale is CM that looks like the bolt that holds on the 3PT arm pins.

 

[metalbender]

I know that Ford 350 dually trucks have washers on the wheel nuts. They were very thick locked on the nut type, not a split lock washer. Old fellow told me once " A day is ill spent if you haven't learned something " I have learned, thanks.

 

[D2Cat]

If you have a loader, the bolt could be one that bolts the subframe to the tractor.