Three Point Draw Pin Nut keeps coming off - how to secure it

[NorthIdahoCatJuggler]

I've been running my Kioti CK3510 for a few years with a land pride brush hog attachment. Suddenly, this summer, I have destroyed three of the lower 3-point draw pins. The cause is the same each time. The 7/8" nut vibrates off during mowing and with it goes the large 7/8" flat washer and matching lock washer. The pin then rattles around in the hole until the threads get destroyed. It's always the same pin, always on the left side of the tractor.

I have taken to buying these pins in bulk at my local tractor place. I'm a big guy and have torqued the heck out of the nut before running the mower. I even put some loctite blue on the threads once, still the nut vibrates right off.

Any suggestions as to what I am doing wrong? See photo taken after hosing down the tractor this morning after mowing for about an hour. The nut and two washers are just GONE.

I'm about ready to spot weld the freaking nut in place, but hopefully there's a less drastic solution.

This is clearly a case of a "loose nut behind the wheel." Thanks in advance for your assistance.

Thanks,
Mark
North Idaho Cat Juggler
YouTube: @catjuggler333

 

[5030]

Put locktite on the threads and use an impact gun to tighten the nut with a heavy duty split ring lockwasher between the frame and the pin.

 

[workinonit]

I see a ton of space between the saddle of the QH and the pin. Are you supposed to be running bushings? Is that a CAT II hitch with CAT I pins on the cutter? Something is not right there. That wobble and slop are probably what's causing the nut to loosen.

 

[Gee Ray]

Do as 5030 and then run a second nut behind the first and lock them together.

You could also drill a hole and put a cotter pin to hold the nut from backing off. Use a castle nut just like a trailer axle.

 

[NorthIdahoCatJuggler]

I see a ton of space between the saddle of the QH and the pin. Are you supposed to be running bushings? Is that a CAT II hitch with CAT I pins on the cutter? Something is not right there. That wobble and slop are probably what's causing the nut to loosen.

Thanks for the speedy suggestions. It's a cat one Quick Hitch. No bushings needed to adapt Cat 1 pins. The photo is taken with the 3-point completely lowered. When in use the pin rests correctly in the hitch. This has also been working fine for years and just suddenly started being a problem. The right hand pin is original and has never worked loose.

 

[workinonit]

All of that may well be true but the spring loaded keeper on top should engage the top of the pin with little to no space or play. That would drive me nuts. There are a dozen easy ways to keep a nut on but that slop needs to be removed. Probably doesn't matter as much with a bush hog or FM but you couldn't run it like that with anything else.

 

[LouNY]

I would have said it needed a bushing also looking at the slop. My thought is that the hitch is grabbing the pin while your raising and lowering the brush hog which is rotating the pin to loosen the nut.

 

[1 of U]

drill it with a 1/8 bit and pin it

 

[ruffdog]

While the one on the left is getting loose the one on the right is probably getting tighter and tighter. Yep, clean it and loc-tite it...forget it.

 

[oosik]

I would consider a larger diameter pin or bushing. Less slop. Then LokTite with a double nut. I think workinonit has identified the problem. The top spring loaded keeper is not engaging the top of the pin. Too much slop.