Kubota ZD21 hydro rebuild

[fatjay]

One oil change from the premium, went to mow a around the yard and circulate the fluid real good, then did another fluid change. Took it over to my fathers to mow a bit. He took it for a spin, not bad for a first time operator. Ran perfect, just a couple things need adjusting. The throttle cable needs lubed, grease points greased, the deck wheels need adjusted. Nothing major though.

One thing has to change, the R4 tires need to go. Tight turns dig in and ruin the lawn.

 

[Spanner]

Rear wheels are on the wrong side for forward traction. :2cents: (Unless you intend them that way round?)
Well done for getting it back together.

 

[KWentling]

Rear wheels are on the wrong side for forward traction. :2cents: (Unless you intend them that way round?)
Well done for getting it back together.

I noticed that too. Mine has turf tires, and you have to be gentle when turning or it will tear up the grass too, so I'm not sure you would gain much by making the change to turf tires. I'd do some research first. Those tires are expensive.

I understand the oil situation. My Kubota dealer options are 100 miles in one direction, or 140 in the other. I keep a 5 gallon pail of it on hand. I looked into using Chevron oil as it is local but it was not stocked in town, so never made the change.

Nice looking mower. Mine is the fabricated deck, but other than that and the tires, is identical. Mine has 1550 hours. Yours looks better taken care of than mine. Mine was owned by a commercial mowing service in its previous life. Just noticed yours doesn't have the roll bar that mine has.

 

[fatjay]

The previous owner included the turf tires, so it would just be $10 at the local tire place to swap them. The R4's when going into a hairpin turn even very slowly, they dig without hesitation. I can understand why the previous owner did it, seeing his yard it was non-stop 30 degree or more hills. My yard is flat, but I have a lot of obstacles and tree's to mow around.

Mine has 950 hours, but I haven't checked if the hour meter works. I'm glad it doesn't have the ROPS, I have a lot of low tree's to drive under.

 

[KWentling]

My ROPS is folded down for the same reason. I have thought of removing it entirely.

 

[Taipa]

A year ago bought a GZD21 high rise that had done 720 hours. Had been going well and thought it was time for an hydraulic oil change - Kubota Oil, new filter.
After ten hours running, a loud metal on metal noise from LHS drive meant the mower went on the trailer into the workshop and now six months later have stripped it down to clutch/transmission component parts. Initially thought it was end float issues on the rear axle - some wear but the jammed transmission drive shaft lever necessitated further exploration.
On stripping clutch/transmission discovered totally destroyed - thrust ball bearing race. In NZ Kubota parts are horrendously expensive. I can get the HST Assembly (K2011-10122) for $3500 shipped from Japan or could possibly get away with replacing just the thrust ball bearing (K2011-01540)

Before I make a decision which way to go I'd appreciate forum members ideas on what may have caused the ball race to fail. I can't afford to have this happen again. My time doesn't cost me but the parts sure do.
Are there alternative parts sellers I haven't found yet?
Regards John

 

[RickB]

That rotating group is trash. I壇 say insufficient oil quality contributed to the failure. Either the wrong spec oil to begin with or the proper oil left in beyond the service life of the additive package. Or a plugged filter, low charge pressure or abnormally high oil temperature. I壇 think real hard about putting the complete unit in it.