Stripped front hub

[PILOON]

Was snow blowing today and kept hearing a metallic clank or crack sound mainly whenever I raised the blower to reposition.
I ignored it believing my lift arms were simply contacting the toolbox or similar item.
My wrong!
My front wheel hub was leaving the tractor, all the stud holes were chewed up and elongated to the point that I really do not understand what kept me afloat.

To make it worse I did torque the studs not all that long ago.

As field emergency repair I removed one bolt and added a big washer then another and did same.
Made it back to the shop door OK.

I then proceeded (using the good wheel as a template) to make a new wheel center that consists of the 2.5" center hole and using the good wheel as my pattern, drilled out the 5 stud holes.

I rough trimmed this homemade center on my chop saw and stick welded it to the rim.
All in all I spent close to 5 hours creating this new wheel center but really had no choice as I know for a fact that not only is the rim pricey, but also hard to find as my CUT is a Mitsubishi MT180D.

Think I should be good for a long time as my center is now 1/4" thick and naturally I did use longer bolts to attach and new lock washers.

Oh. should mention that this is the second time as the other rim did the same thing 2 years back, funny I almost did the mod on this wheel this fall but got lazy.
Also both times it was the right wheel.

For sure I probably would get shimmy at road speeds but since my top speed is about 8 MPH I won't loose sleep over it.

And a road/work test proved out my repair!

 

[tugboat-2]

WOW PILOON,...that is some serious, precision repairs,...especially for the home shop!!! Since it all worked out and passed the road/work "test",..I would have to say Congratulations are most definitely in order! You should be proud! AND,..look at the money you saved, . . (better not tell the Mrs,..she'll suggest you take her out for dinner,...ha, ha!)

CHEERS!
. . tug

 

[magicheater]

You have to admire ingenuity when you see it. Congrats on the mens gold too.

 

[RoyJackson]

Great job, but I am very curious if you have any thoughts on what caused the failure.

 

[kebo]

Great job, but I am very curious if you have any thoughts on what caused the failure.

I'm curious what happened to your studs?? The last time I had a rim come loose (on my 16ft trailer while hauling my tractor) the studs AND the rim got chewed up really good. Did the studs not need replacement after that????

 

[Kubota 2350]

 

[PILOON]

On the Mitsu they are machine screws (bolts) that screw into the hubs.
All the bolts were badly mangled where contact was made with the rims and therefor scrapped, however they came out perfectly with no damage to the hubs.
I tried to punch a witness mark on the hub and found it to be case hardened to the point that it dulled my center punch, hence no inner thread damage.

While a good all around system, mounting a wheel is a bugger as you kinda balance the wheel midair trying to align a bolt blindly. Usually I use a screwdriver to lever into alignment and thread a bolt in by finger turning until the first one catches.

WHAT CAUSED the failure?
Since this is the second time on the right side I suspect torque either pushing snow off to the right side with my one-way plow* or usage with my FEL loading and prying with the tooth bar causes torquing forces that tend to unscrew the bolts on the right side all while tightening the left side.
Definitely hard work related forces.

The only other improvement I can think of would be to safety wire the bolts in pairs to prevent them from unscrewing, but drilling the heads of graded bolt heads would be a chore. I'll check torque more often instead.
(Like tomorrow after couple of hours of working)

For sure with 1/4" hub centers I don't expect to see this happen again

*when plowing, snow loads tend to push the tractor sideways to the left so I steer to the right resulting in the wheels side-slipping and kinda grabbing at the same time.

 

[kebo]

I wonder if some of the good Loctite threadlocker would help? I'm going to assume they already have a lockwasher under each bolt?? If not, maybe that would help? If you really felt ambitious, rather than wiring them like you suggested, maybe you could fabricate some sort of a locker ring that would fit over the bolt heads, which itself bolted to the rim on top of the bolt heads. Just a thought.

 

[tugboat-2]

Kebo: ....I do believe Piloon mentioned that he had replaced the capscrews and the "lock washers".

I'm wondering if those capscrews go right on through and if it would be practical to instal another lock washer and nut on the back. Is there room to use a longer capscrewfor that purpose,..or are they blind holes?

The side thrust from your one-way seems a reasonable explanation and inside nuts would help if enough room? Good luck with it mon ami !

CHEERS!
. . tug

 

[banjodunn]

G'day it sounds to me like bad engineering on behalf of the manufacturer wheel studs /bolts are designed to hold the wheel to the hub not take the weight of the machine that is the job of the spigot on the hub. I have seen a couple of machines over the years that have been made like that and the reason i see them is usually "what am i going to do" they should not be allowed to do it but they do. Sounds like your repair worked well i would make it a routine to pull the bolts out and check for any fretting say every time you change the oil not much effort to save a load of pain


Jon