Hoe frame welding question.

[wmasmith]

I searched for this but i didn't have any luck. I have a 2017 XR4140H with LB3104 hoe with the factory frame. I worked it real hard this past weekend and the 8 bolts that mount the hoe frame to the sub frame kept working loose. What kind of trouble am I looking at if I weld the frame together instead of just relying on the bolts. I can probably take it apart one bolt at a time and red loctite it, or tighten it up and tack weld the nuts. I'm just worried if I tack them or loctite I'll still have it shift around under load no matter how tight I get the bolts. There's provisions for using a toplink but I would be worried about breaking the rear axle housing. I've attached part of the manual that shows the mount of the frame to the subframe. What do you guys think?

 

[Shield Arc]

What do you think about making some short welds to hold it together? Place the welds where they are easy to cut out at a later date.

 

[wmasmith]

That's an idea. Was planning to retain the bolts but grind away the powder coat and bevel the areas that I can get to to provide a good clean surface. I can probably get to all of the areas with a 4" grinder and a cutoff wheel if need be. I'm just concerned about moving the stresses from the bolts to the box tubing. Of course if that happens I can always just heavier wall tubing and rebuild the subframe if need be. Thanks for the input. Anyone else.

 

[Shield Arc]

When you make your welds, use 7018. And make sure you fill in the crater / stop good, do not leave the crater under filled. The crater will be the first place the weld will start to crack.

 

[dfkrug]

There's provisions for using a toplink but I would be worried about breaking the rear
axle housing.

There's your answer: use the toplink connection.

That type of subframe has been around a long time and is used on lots of tractors. It just flexes too much if you
don't use the toplink. Stress on the toplink connection on your tractor is not severe; it is nothing like
you would have with a 3-point hoe.

Kioti hoes use that design and I have seen where the braces are welded, but the flex does not go away.
It is near impossible to keep those bolts tight if you have that kind of flex.

 

[Billself]

when welding anything the heat from the weld makes it a little more brittle so if you do weld it up to take flex out, some thing has to give. If i was to weld it I think i'd tack the bolt heads enough to keep them tight but not all the way around then i think i'd brace it by using top link or bracing sub frame with steel brackets to solid it up a little but in the long run something will give if worked really hard.

 

[wmasmith]

Thanks for all the input. I think I'll start with the top link and go from there. I can always do more if I need too.

 

[dfkrug]

I think I'll start with the top link and go from there.

I have been making subframes for a while and I have never heard of a tractor incurring
toplink bracket damage when bracing a ladder-style undermount subframe. This issue
is moot with the more popular 4-point subframes. There is a reason that the big
makers (Woods, JD, Kubota) have all gone to 4-point setups.

If you go to YouTube, you can watch many tractors with subframes in operation. Some
of them have HUGE amounts of flex.

 

[farm boy00]

I searched for this but i didn't have any luck. I have a 2017 XR4140H with LB3104 hoe with the factory frame. I worked it real hard this past weekend and the 8 bolts that mount the hoe frame to the sub frame kept working loose. What kind of trouble am I looking at if I weld the frame together instead of just relying on the bolts. I can probably take it apart one bolt at a time and red loctite it, or tighten it up and tack weld the nuts. I'm just worried if I tack them or loctite I'll still have it shift around under load no matter how tight I get the bolts. There's provisions for using a toplink but I would be worried about breaking the rear axle housing. I've attached part of the manual that shows the mount of the frame to the subframe. What do you guys think?
View attachment 527639

You say it is a 2017. If so I wouldn't modify it until it is no longer under warranty or talk to the dealer with these problems and see what their advice is. Unless you don't have a warranty. I would imagine welding it would void all warranties of the machine.

 

[3Lfarms]

It should have been delivered with the top link in place. Install it and your problems will disappear.
Locktite on the bolts is fine if it makes you feel better.
You can see the top link installed the day I picked up my tractor.