Kubota Diesel Zero Turn Questions

[DenisM]

Looking to buy a new diesel zero turn mower and have always liked Kubota equipment. Two local dealers I called gave very vauge answers to my engine questions.

Do the smaller zero turns, like a ZD 1011,require DEF?
Do these smaller engines have an EGR system?
Do these smaller engines have a common rail, high pressure, ECM controlled injection system or do they have a mechanical, older style mechanical injection system?

If newer engines have these features how far back would I have to go to get one without them?

I believe these engines must meet tier 4 standards, but the government web site I checked was too complicated to get any answers from.

Thanks for any insight.

 

[RjCorazza]

My ZD1211 is 24.8 HP and no dpf. I believe it is exactly the same as my older ZD326 emissions wise. Both mechanically injected, no dpf, no computer control. There won't be def on any of the Tier4 ZD mowers.
The (now discontinued) ZD1511 was a mechanically injected, dpf equipped machine that was very problematic for Kubota.

I have been very satisfied with both of these machines. The 1211 has a 72" deck, and I have no power issues. It's not "beast mode" like my previous ZD331 72", but it gets the job done.

 

[Fladogman]

My ZD1211 is 24.8 HP and no dpf. I believe it is exactly the same as my older ZD326 emissions wise. Both mechanically injected, no dpf, no computer control. There won't be def on any of the Tier4 ZD mowers.
The (now discontinued) ZD1511 was a mechanically injected, dpf equipped machine that was very problematic for Kubota.

I have been very satisfied with both of these machines. The 1211 has a 72" deck, and I have no power issues. It's not "beast mode" like my previous ZD331 72", but it gets the job done.

You correct, the engines are under 25 hp so not Def or other emissions control stuff required.

 

[5030]

I'd like one, problem is my wife says my wallet isn't fat enough. I tend to agree and owning a pair of gas zero turns now, one would be too much as there is only the 2 of us anyway.

I've done quite well with both actually, lots of hours, lots of acres mowed and lots of maintenance as well.

I do have a feeling that the Kohler V twin on one of them is going to have to be replaced soon. Has a strange sound coming from within. Runs fine for now, probably a wintertime project.

 

[RBsingl]

My ZD1211 is 24.8 HP and no dpf. I believe it is exactly the same as my older ZD326 emissions wise. Both mechanically injected, no dpf, no computer control. There won't be def on any of the Tier4 ZD mowers.
The (now discontinued) ZD1511 was a mechanically injected, dpf equipped machine that was very problematic for Kubota.

I have been very satisfied with both of these machines. The 1211 has a 72" deck, and I have no power issues. It's not "beast mode" like my previous ZD331 72", but it gets the job done.

I have the same D1105 Kubota engine in my F2690 as your ZD1211 and it has no problem with the 72" deck. I do have the rear discharge deck which probably takes a little less HP in heavy grass since discharge is across the entire width of the deck instead of funneling the clippings into a smaller chute.

The Kubota has taken over mowing duties from my Deere 955 compact (33 HP 1.4L diesel) with a 72" midmount. With the deck out front, I can mow much faster and get a cleaner cut since the only wheels in front of the deck are carrying only part of the deck weight instead of the heavy tractor wheels pushing down the grass.

These sub 25 horse derated engines are pretty basic simple mechanically injected diesel engines and the equipment safety controls (aka OPC) are potentially the most troublesome part of the equipment.

Rodger

 

[Hay Dude]

The Kubota 1105 diesel is just “de rated” to meet the max HP rating without a DPF. Even with de-rating I think it probably has good torque to be able to run the 72” deck.

I might pick up a used ZD-1211L and add it to the fleet next summer.

 

[RjCorazza]

I'm not a fan of the 1211's fuel system. It draws off both tanks at the same time and the fuel gauge shows the total fuel available. A crossover tube keeps the pressure equal. Sounds good in theory, but I am constantly having one tank draw either faster than the other, or just from the one tank period. I replaced the individual tank filters after only 100 hours (normally get 400 hours out of them), and it's back to unequal fuel drawing. It started doing this at 1200 hours.

I plan to remove the individual tank filters and install a Racor water separating filter after the tank "T" fitting. There is good flow from each tank before the filter, so I suspect somehow one tank has dirtier fuel than the other and creating an unequal draw.

 

[Hay Dude]

I'm not a fan of the 1211's fuel system. It draws off both tanks at the same time and the fuel gauge shows the total fuel available. A crossover tube keeps the pressure equal. Sounds good in theory, but I am constantly having one tank draw either faster than the other, or just from the one tank period. I replaced the individual tank filters after only 100 hours (normally get 400 hours out of them), and it's back to unequal fuel drawing. It started doing this at 1200 hours.

I plan to remove the individual tank filters and install a Racor water separating filter after the tank "T" fitting. There is good flow from each tank before the filter, so I suspect somehow one tank has dirtier fuel than the other and creating an unequal draw.

Funny, I thought that would be an improvement, too.

My ZD 331 has the separate tanks as you well know.
I guess Kubota eliminated the twin separate tanks as a cost cutting measure? That eliminates the “low fuel” warning light and sender for the reserve tank and the valve to switch the tanks.

 

[5030]

I plan to remove the individual tank filters and install a Racor water separating filter after the tank "T" fitting. There is good flow from each tank before the filter, so I suspect somehow one tank has dirtier fuel than the other and creating an unequal draw.

This time, buy the Chinese Racor clone and install a genuine Racor element like I did. Much cheaper and you get the same result. On big trucks with saddle tanks, they use an inline one way valve so the brother tank draws down equal to the other tank. That is why, if you do a partial fill, you always fill the tank that has the fuel line drawing from it.

Interesting in as much as neither of my M9's have that issue and they both have saddle tanks so I'm thinking that they have the one way valve, though I've never looked and the crossover line under the gearbox has a shield over it anyway.

 

[mikester]

Funny, I thought that would be an improvement, too.

My ZD 331 has the separate tanks as you well know.
I guess Kubota eliminated the twin separate tanks as a cost cutting measure? That eliminates the “low fuel” warning light and sender for the reserve tank and the valve to switch the tanks.

I've been thinking of adding a second fuel gauge on my ZD326 - the low fuel light doesn't seem particularly useful, especially on hilly ground.

 

[workinonit]

i have a 1211 with a 60" deck that I run a mulching kit on. I don't think I would want a 72" deck with a mulcher but it may be okay. I probably cut grass differently than most of you. I have centipede and cut it down to 1.5" so I can bog down even the best of mowers. I do really like the 1211. So much better than any of the JDs that I have had. I still run my old JD 717A. It was my first ZT. Still the best cutting mower that I've ever had as far as appearance.

That fuel tank setup is strange. But mine is soo good on fuel that it doesn't matter all that much to me. I just filled up Wednesday and the two tanks were fairly close in level. Not exactly but probably within 1/4 tank.

 

[Hay Dude]

I started looking at 1211’s to replace my ZD331.
My concern is the drop off from 31HP to 25HP is going to be noticeable. Kubota says the new 72” deck uses less power. It’s the same 1105 diesel engine, which is probably the best 25-35HP diesel ever built.

What I might do is grab a used 1211 and keep/use the ZD331 for the times we have to cut super tall grass? Make it like a “rough area” mower.

For what my ZD331 would sell for (maybe $7,000???) it isn’t worth selling. They are tanks and built to last a long time.

My F3680 is something that has allowed me to take steep angle cutting tasks on, but it was a lot to spend on a mower that only cuts small steep areas. Unfortunately, mowing contractors aren’t typically paid for mowing a piece of ground where a small percentage is steep.

 

[workinonit]

I never ran a 331. Honestly, the primary reason I got the 1211 was the way the deck raise and lower works. I cut around 38 live oak trees and this mower is the only one I could find that will raise to any height. I can just bump the pedal and get an inch more height to get over tree roots. Before I was doing that with a mechanical pedal and my knee hurts when I think about it.

 

[Hay Dude]

I never ran a 331. Honestly, the primary reason I got the 1211 was the way the deck raise and lower works. I cut around 38 live oak trees and this mower is the only one I could find that will raise to any height. I can just bump the pedal and get an inch more height to get over tree roots. Before I was doing that with a mechanical pedal and my knee hurts when I think about it.

ZD331’s are probably the best HD diesel 72” ever built. They are the precursor to the 1511 but no emissions like on the 1511.

At 31HP and diesel, Mines beast mode. Love it. My son runs it and doesn’t treat it as nice as I do. Currently shows about 2500 hours and no signs of slowing down, but time will eventually take its’ toll and I know a replacement is going to be needed for everyday use.

 

[arto98607]

This time, buy the Chinese Racor clone and install a genuine Racor element like I did. ..................snip.......................

They are cheap that's for sure, but be aware that they do not have NPT threaded barb fittings, which is OK as long as you plan on using the barb fittings that come with the chi*com RACOR clones.

NPT 90* ell etc. will not fit without some adjusting (re-tapping ?) which is not a big deal for most of us I think.

Cheap clone:




I replaced the secondary filter on my F3060 with 2 micron filter had both filter housings on my shelf - ended up using genuine RACOR for this reason.

RACOR in F3060:

 

[5030]

First thing I did was toss the IFJF filter and replaced it with a Racor even though the reviews I've read on various websites say the the IFJF cartridge is as good as. I don't trust reviews today, too many biased reviews anyway.

Far as the fittings go, I just chucked them in one of my engine lathes and reduced the OD to the ID of the supply hose plus .030, no big deal and as far as the barbs go on the fittings, really not needed as there is no positive pressure in the fuel lines or the fuel polishing unit, it's all negative pressure produced by the fuel pump on the engine.

I did find some of the 'reviews' entertaining. " the fuel bowl melted". Of course it did. It's a Diesel filter not gasoline. The stupidity of some people amaze me.

Finally, I see you can now buy the clone bases with a purge pump built in which will eliminate hand priming of the filter entirely.

Both mine are mounted to the loader upright that is attached to the tractor frame but protected by the upright itself and easy to see as well as drain the bowl and change the filter. Gonna put one on my diesel pickup truck as well but that one will be frame mounted.

 

[arto98607]

Sounds good!

Just for the record - F3060 fuel system is little different with the primary filter being on the suction side of electric fuel pump, and the secondary filter is on the positive pressure side.

No idea how much pressure there is, but it must be pretty low.

 

[WM75Guy]

I like my 2016 ZD1211 60" side discharge. I do want to replace it with a new F2690 60" rear discharge, want the flip up deck so I don't have to crawl around on the ground to clean the deck or change the blades. Dealer is going to give me $10,000 to trade mine in, which is fair. Only problem is there are only 2 F2690 machines in Texas, one near San Antonio and one in the Panhandle, not close to East Texas. Both have 72" decks and the dealers are not willing to do a trade with my Kubota dealer. If we order one it is 6 months on the mower and unknown wait time on the 60" deck.

 

[m7040]

I started looking at 1211’s to replace my ZD331.
My concern is the drop off from 31HP to 25HP is going to be noticeable. Kubota says the new 72” deck uses less power. It’s the same 1105 diesel engine, which is probably the best 25-35HP diesel ever built.

What I might do is grab a used 1211 and keep/use the ZD331 for the times we have to cut super tall grass? Make it like a “rough area” mower.

For what my ZD331 would sell for (maybe $7,000???) it isn’t worth selling. They are tanks and built to last a long time.

My F3680 is something that has allowed me to take steep angle cutting tasks on, but it was a lot to spend on a mower that only cuts small steep areas. Unfortunately, mowing contractors aren’t typically paid for mowing a piece of ground where a small percentage is steep.

Replacing my ZD331 with a 25 HP 1211 is not in the cards. I need the power for the tree farm where there is long growth around the trees. The 1211 would likely bog down.

 

[Hay Dude]

Replacing my ZD331 with a 25 HP 1211 is not in the cards. I need the power for the tree farm where there is long growth around the trees. The 1211 would likely bog down.

The 1211’s seem to run a 60” deck happily, but a 72” deck seems the upper limit. I would use it for lawns 98% of the time and keep the 331 around for nasty stuff.