420c

[Hillbilly6]

Hey all,

Looking at a 420c with a blade. Only seen pictures of it and a video of it driving around. Tracks look like they’re gettin loose and no more adjustment on the rod. Is it possible to completely suck in the adjuster and remove a link? Or not enough there to do that?

Thanks

[Lavoy]

Yes, you can, but by doing so you are doing it knowing that you are running the tracks and sprockets to destruction.
Lavoy

[Hillbilly6]

Any other options? Other than complete replacement?

Thanks

[Stan Disbrow]

Hi,

Well, I would be replacing the pins, bushings and sprockets at the minimum. Meaning 420c sprockets. I would never contemplate removing a link from the chain.

And, replacing just those parts would occur after I went through the rest of the measurements on the chain, rollers and idlers. It might just measure out worn enough to where I would replace all the parts. They do all wear on each other. Chances are yours are worn too far given the description of the adjustment.

Replacement these days would be with JD350 rails and that means cutting the teeth off the 420c sprockets and welding on new rim sprockets.

Stan

[Lavoy]

As long as you links are good enough shape to warrant it, rebush your exising rails, you will in all likelyhood never wear them out again.
I am working on a new production run of pins and bushings, would hope to start rebushing tracks by this fall if not earlier.
Lavoy

[Hillbilly6]

It’s on Fraser Auctions, it’s a consignment sale for Killarney. If you’s have time to take a look, there’s pictures and a video. If it’s worth I’ll drive the 3 hours to really go take a look, but a quick second opinion would be great. I am diesel mechanic by trade, so working on the unit itself isn’t an issue.

I appreciate the feedback so far!

Thanks

[Lavoy]

I can only see one rail, but based on the one I can see clearly, the links look good. Pins and bushings were shot a few hundred hours ago, so no way that is original hours. The pitch is already so far off on that crawler it is eating the sprocket, taking a link out will just finish wrecking it.
It has also had the engine replaced, and the transmission top cover/shifter assembly replaced, or there something else odd. Looks like a decent crawler otherwise.
Lavoy