Bush Hog crazy wheel revisited.......

[Snowback]

LOL! That one had the best clarity from a quick Google image search, eh Bruce? I didn't even notice you had used that! I'd say great minds think alike, but mine is only "so-so".

This type of image was shown earlier in the other post, but the importance of the differences of angle are crucial. The best design will create the angle right after the pin exits the pivot housing as in this picture below. If you can make your wheel and connecting pin/shaft look like this, then it will work. I think that it must have been bent in the past somehow and that has straightened it out to the point where it will no longer "caster" effectively.

View attachment 473540

Here's a better picture of my tailwheel setup. I really can't see where there were any drastic bends or modifications except where I cut the yoke 15 degrees and reversed it to angle the shaft back more. The yoke shaft does (or did) line up in a straight line to the wheel shaft but it looks like thats the way the **** thing was made. Only thing I can think happened was the wheel assembly was replaced with another from a different mower. I don't know how to proceed now.View attachment 473675

I think your unit is very similar to the one in my picture above. The cut and reweld just convoluted the force diagram. In fact I think it tried to take the bend back in the wrong direction. Go back to your original straight fork design, (just like in the top picture), and then fix the bend at the top where the pin connects with the fork to the wheel axle. It has to have a very noticeable offset just like in the picture above.

And for clarity - this does not mean the wheel can simply be placed behind the pin like in your picture. It HAS to be behind the straight line created from the pivot shaft down to the ground. To make this easier for you to see, start by adjusting your tail wheel into the highest position where the top pin/shaft is perpendicular to the ground. Then look at where the wheel axle lines up. Currently it will be essentially right below that pivot point. You'll need to bend the pin connection back into shape as in the example pictures, or perhaps get a new bracket for an easy solution. (Of course after you have fixed the bracket itself which can be straight as in the examples.)

Direction of the angle does not matter as there is no front or back. The wheel will pivot behind automatically and pull properly as soon as the caster is sufficient. In my eye there must have been some prior sudden impact that bent the connection between the top pin and the wheel bracket and that has caused the problem. Also - as noted above, be sure to make sure the wheel ends up perpendicular to the ground. (Bottom of wheel is flat and level on a level surface.) That support bracket may need to be tweaked to do that.

Here is a source to some replacements that might make your life even easier for less than a hundred bucks. (Make sure shaft pins are compatible size.)

http://www.gaequipment.com/ProductD...r6jgskbQ7blW7tAc90i6uehx9lEfWHbR-kaAvMf8P8HAQ

Satguru Trading Inc. - Mowers Parts Manufacturers & Exporters in India.

Check out how big your pivot pin and shaft are. Maybe you can just get a clean new bracket and slap in your wheel... Replacement Rotary Cutter Tail Wheel Fork 1 1 2" Post 4 3 4 to Hole 5 1 2" Width | eBay

 

[SPYDERLK]

... Also, it appears the pivot collar is twisted a little sideways from perpendicular. This is contributory. Try to make it as near perpendicular to the bushog body in the left/right plane as possible.

Here's a better picture of my tailwheel setup. I really can't see where there were any drastic bends or modifications except where I cut the yoke 15 degrees and reversed it to angle the shaft back more. The yoke shaft does (or did) line up in a straight line to the wheel shaft but it looks like thats the way the **** thing was made. Only thing I can think happened was the wheel assembly was replaced with another from a different mower. I don't know how to proceed now.View attachment 473675

Addressing that slight twist couldnt hurt

 

[Snowback]

A picture of what my mind sees...

Doing this will result in what you see here:

Good luck!

 

[LD1]

YEp, when you made your angled cut in the yoke and re-welded, you didnt go high enough.

 

[aczlan]

A picture of what my mind sees...

View attachment 473683


Doing this will result in what you see here:

View attachment 473684


Good luck!

Rather than going that, what about cutting it just below the crossbar at a 10ish degree angle and flipping the cut pieces like he did with the lower cut? That should push it out more and be less work.
What you want is a line straight off of the pivot pin down to clear the "rim" of the tire. Otherwise there wont be enough offset and it wont track straight (as you found out).

Aaron Z

 

[GManBart]

I had something similar happen a while back, but the cause/fix was quite different. I found that the washer and clip on the top of the shaft were binding, and not letting the wheel swivel properly. I added a large set screw spacer and a new pin to keep it in place and the problem of the wheel turning into a plow went away immediately.

 

[Snowback]

Rather than going that, what about cutting it just below the crossbar at a 10ish degree angle and flipping the cut pieces like he did with the lower cut? That should push it out more and be less work.
What you want is a line straight off of the pivot pin down to clear the "rim" of the tire. Otherwise there wont be enough offset and it wont track straight (as you found out).

Aaron Z

Yes - that will work too. :thumbsup: Anything along these lines will do the trick. It's important to note that the original cut and weld job is taking the yoke back in a direction opposite to the original slight bend just after the pin, so it's working against itself even worse right now. My intent was simply to remove any complications and use as few straight lines and angles as possible so that this becomes a very basic geometric study. It involves more steps indeed, and I acknowledge that. Personally - My OCD would act up if my tail wheel bracket looked like Ostrich legs, hence my more laborious purist method to get back to this ultimate setup of wheel axle in relation to the pin axis.

However it gets done is simply part of the fun. Just like the whole journey/destination thing!

 

[orangeandgreen]

Might be time to drop $30 and get a new fork.

King Kutter Rotary Mower Wheel Fork | Agri Supply #1451

 

[kebo]

Might be time to drop $30 and get a new fork.

King Kutter Rotary Mower Wheel Fork | Agri Supply #1451

I would tend to agree with this option. That original tail wheel fork has been modified a bit much, for $30 it might be best to start anew.

I also agree with what some others have said, the angle in the fork needs to be as close to the pivot point as possible.

 

[jaken]

Ordered a new fork. Will post the outcome.