Kubota RY-600D Tracked Dumper track Lock Out Problem

[DKent]

Hello there. I own a couple of Kubota walk behind dumpers, a RY-601D and RY-600D. The 600 is definitely older, inferior machine to my 601- both quite old.
The 600 I just bought on auction and I'm noticing that the left track doesn't want to lock out. I've noticed even the 601 seems to be finicky when it comes to locking out the track and locks out better when loaded. For my new to me 600 the machine makes a firmly clicking sound and doesn't like to lock out on the left side when I attempt to engage it in the forward direction. Without attempting to lock, it tracks just fine in forward and reverse, yet I notice if I'm on a hill, there isn't much resistance to it rolling back which is also a bit unnerving.

I'm curious if anyone has information or experience on the drive mechanisms? or where to start? The right side locks out just fine and might start with checking the cable (yeah, cable) is adjusted well. I assume there maybe some internal clutches to this little machine? I bought it as a back up to my 601 that isn't in the best shape either, but I'm realizing the 600 is in tough shape.
Any ideas where to start?

 

[heymccall]

Do you have operators manual?
This is from KC70 manual (only one easily found).

 

[DKent]

Thanks for the quick response Heymccall. No, I have no manual. Both of these machines appear to have been imported from Japan- according to my local Kubota dealer. "Grey" market? There isn't a parking break, but from my limited experience with tracked equipment, it usually doesn't readily role back if I'm not applying the forward motion lever. Yeah, it might slowly creep on its own down a hill, but this thing seems to have no resistance to rolling back. My 601D tends to have a little rollback when on an incline as well, but nowhere near as bad. I haven't studying the drive mechanism all that well, but it definitely looks like a single sealed unit. Your KC70 is a much newer machine.
I did just order a Messersi high tip, due to be delivered next week, but I'm also in need to get these Kubota units more reliable and I have yet to find much of any information regarding the drive mechanisms. It was tough enough just to get HP numbers for OC63 and OC52 diesel motors that are on them to understand how the Messersi unit compares.