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Discussion Starter #1 (Edited)
The rotary cutter's tail wheel bushings on my 503 John Deere rotary cutter wore out over the last twenty years and caused the axle bolt holes in the Yoke to wobble out and the axle bolt itself to almost wear in half.

The damage caused the tail wheel to hang up and refuse to turn around and follow as fast as it should have causing the wheel to hang up and take long divots... mostly after backing up and then going forward.

The first step in the repair was too grind-off the welded on steel washer that holds the yoke pin on the rotary cutter's adjustable arm.

Then I took the yoke over to the vise and drilled out the original 5/8 axle holes to 3/4" to accept two 3/4" grade 5 bolts I was using for shoulder bushings.


Since the new 3 piece wheel bushing kit from John Deere came with a smaller OD axle bolt...11.75MM instead of the original 5/8 axle bolt I ordered a drill bit from MSC, 11.80MM was the closest I could come. I thought by keeping the axle holes as close as possible to the new axle bolt's OD the repair would last longer.

Next I cut the 3/4" bolts off the thickness of the yoke, drilled them for the new 11.75 MM axle bolt and welded the bolts to the yoke.

Because the 3/4 bolt heads made the yoke wider I had to buy another 11.75 MM axle bolt from John Deere. I cut both bolts in half and welded them together to get the proper length.

Then I stuck the yoke's pin back through the rotary cutters adjustable arm and welded on a new washer that I just happened to have laying around that fit perfectly over the pin.

The repair has been working flawlessly now for two cutting seasons. Matter of fact the wheel reacts immediately when backing up and going forward now, because it turns so fast now It has quit taking plugs out of the yard and fields and I have started using it once again to mow the yard.


I think because I took away some length from the yokes pin when I welded on the thicker washer the yoke pivots better. There is less up and down slop now and less opportunity for dirt to get in and puke things up now.



First picture shows the 3/8 washer I used to hold the yoke on laying on the welding table

Second picture shows the worn axle bolt

Third picture shows the washer welded on

Fourth picture shows the the 3/4" grade 5 bolt(shoulder bushings) welded in.

I should have taken more pictures but it's all I have of the fix Thanks for looking.
 

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Nice work on the wheel repair tacket! Slick idea using a bolt as shoulder bushings for the new hole. I would have never thought of doing that. :cool:


That old axle bolt looks like the one I replaced on my boss' ZTR this summer. Amazing how some slop from wear combined with dirt in the grease can wear them down.


Thanks for entering the contest! :)
 

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Discussion Starter #4 (Edited)
Thanks guys.

I posted this fix because I thought other bush hog owners might have the same problem. It was such a simple fix with such great results I should have did it long ago...:)

I'm hoping the grade 5 bolts are harder than the new axle bolt, it they are, the axle bolt should wear long before the 3/4 bolts.

I should mention too that the new bushing kit came in three pieces and all three pieces were made of plastic.
 

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Way to go, Tackit!

Perfect timing as I'm having a little argument with my own little (4') Howse brush hog tail wheel :D!

You have inspired me to get off my duff and make the repairs...

Mark
 

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Discussion Starter #7
Glad to hear it Mark. It really is a simple fix.

I wish I had thought about the added width the 3/4" bolts I used for shoulder bushings gave the yoke, I would have ordered a longer MM bolt instead of welding two bolts together.

If the new axle bolt was SAE instead of MM I could have went down to the farm store and bought a longer bolt... or bought a drill rod and treaded it. A 11.75 MM bolt ain't easy to find around these parts. :D

l
 
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