Deere JD770G grader Circle drive repair

Hey everyone, I've got a Deere JD770G grader that has some worn teeth on the Circle drive. I'm looking at two ways to fix it: either replace the whole Circle drive frame, or cut out and replace just the worn tooth segments. Has anyone dealt with this kind of repair before? Would be helpful to know which option worked better for you.

I'd check whether JD has replacement sections available for the circle teeth. Cat does offer them. Can you share a photo of the worn teeth? Like mentioned before, you might be able to build up the worn areas with welding. If you go that route, there are special welding rods available that won't mushroom the way standard rods do. I'd need to see some pictures to say for sure, but depending on how the teeth are arranged, you could potentially swap the worn section with a good section from somewhere on the circle that doesn't get used much, like if you rotated the moldboard completely around 180 degrees.

Cutting Edge in Australia posted a video on Facebook that might help you decide. Actually, it's on YouTube instead.

I found a YouTube channel on fire welding that shows how they do it. Looks pretty impressive and fast.

Deere had a section available that was around 2 feet long, but I'd think building up the worn teeth and grinding them back down to match the rest would probably work better. You could trace a pattern from the good teeth and cut it out so you can grind the worn ones to match. I'm not sure whether hard facing rods would be the right choice for this though.

I'd go with buildup rods for fusion welding rather than hardfacing rods. They're medium hardness so they won't squish out or mushroom from the impact and pounding. It'll cost a bit more but it's your best bet. 7018 would be the cheaper option and should work okay too.

The outcome really comes down to how patient you are and how skilled you get with a grinder. You don't need to get it looking brand new—just good enough to function. I'd say it shouldn't take much effort to make it workable enough to last until the next thing breaks. I've welded up multiple ring gears on flex plates using a coat hanger and an acetylene torch. Even just fixing 2 or 3 teeth was enough to squeeze another year out of them.

Did you end up going with one of those options?

Are you talking about particular rods in mind, or just any type that might work?

You could try this or something similar from a specialty rod supplier. Lincoln makes a build up rod as well, and they have a comparison chart available.