Kubota F series

[arto98607]

Hello all,

This looks like a good thread to bring up my new to me 2000 hour F3060, with a 72" rear discharge deck (RC72-F30). I bought it earlier this season, and have mowed with it about a dozen times or so. I used an old 24 HP Briggs and Stratton powered Encore ZT with a 52" deck for about 10 years prior to acquiring this machine.

Depending on the extent that I felt like mowing, the job would about 3 hours on the ZT, give or take. Mowing with the F machine takes about the same amount of time, but is MUCH more comfortable to ride on for 3 hours at a time than the ZT. Obviously, the agility of the ZT makes a huge difference that the 72" deck on the F machine cannot really improve upon much. Otherwise, the F3060 is an awesome machine.

I am learning to account for the tail swing, though I am still figuring it out. I have not caused too much damage... to anything of any consequence anyway. I have a few questions for the In The Know group:

1. I ran high lift blades on the old ZT, and really liked the cut quality. I did not bag any thing, mostly just sweep up what windrowed, if anything. I bought new Kubota blades from Messicks. I did not realize at the time, but the only Kubota blades available are low lift blades. I am able to find high lift blades, but none with the 7/8" diameter shaft hole- all of them are 1-1/8" diameter. Does anyone know of anywhere to source 7/8" shaft diameter blades for this deck?
2.I note that where I am required to make full lock turns, the grass is pretty stressed...in some places the grass is dead. Everything is pretty stressed due to the dry weather, but the maneuvering areas are especially stressed. I have some steep ground, but most is pretty flat. I have not used the 4x4 lock or the differential lock yet for any reason. Is there an opinion that the on demand four wheel drive causes this stress? I understand it is pretty easy to remove the rear driveshaft...would that be one way to counteract this problem?
3. The deck gearbox gets pretty warm. I can always place my hand on it after shutting down, but I feel like I better not leave it there very long. Is this normal?
4. I feel like it is kind of tricky to keep my mowing lines straight. The ZT was tricky also, but I was able to keep things pretty straight after a year or two of experience. Is this normal, or this there some steering play I need to look for and correct?
5. The deck drive belt came off last week. Since it was partially off, and it was the belt that came with the deck, I thought I would go ahead and install the new belt that I bought right after I bought the machine, thought the old belt was still in pretty good shape. Unfortunately, the gear box sheave seems to be about 1/8" too low, thereby not allowing clearance for the belt to get past it. It seems there is a collet that secures the sheave to the output shaft. It looks like there is room for it to raise up. It appears also that the gearbox would have to be removed to work on it. Has anyone had this apart and can confirm this for me?
6. I read the posting on the driveshaft rebuild issues, and can see that I have project in my future. The driveshaft vibration is not bad yet, but, I can see that eventually it will be. I will reach out to that thread when the time comes. I saved the parts list PDF from the thread already.

Sorry for the long post. I would greatly appreciate input from the collective experience.
Thank you,
Doug Vazquez
Shelton, WA

Doug,
Glad to see another "local" F3060 owner and I hope my suggestions below will be helpful.


Your question 1.

• I got three SS spacers, in order to be able to use blades with 1-1/8" mounting holes. Been running Gator G6 Mulcher Blades 396-814 for one year with those. You will have many more choices with these spacers in place. I may go back to the OEM 70050-94622 blades next time just for comparison.

Question 2.

• Our property is leveled enough that 4x4 is not really needed so I removed the rear drive shaft and have not noticed any grass stressing due to mower turning around, however it's obviously best to avoid "full lock turns" as much as you can and drive in big circles. Bigger the better. (I think F3060 has something similar to AWD when the shaft is in place) Our Grasshopper mower has bar tires and it's obvious to see the wear those cause when the ground is wet.

Question3.

• Have you checked the 90 degree gearbox oil level? I switched to synthetic gear oil.

Question 4.

• Check the steering for any slack, including the "king pin" plastic bushings 070 seen below. Once all good, double check the rear wheel toe-in.

Question 5.

• In my mower the belt had to be flipped on it's back in order to slide out in-between the gearbox lower pulley & mower deck metal. IE the belt was or is wider than "taller" as far as I recall. In any case, it came out after flipping it 90 degrees. The pulley can be moved slightly up on the shaft, but in order to do so you need to un-mount the 90 degree gearbox.

Here is a thread I started little over year ago regarding the 90 degree gearbox in my 1997 F3060 mower.

90 Degree Bevel Gearbox on Kubota F3060 - 72" Rear Discharge Deck

I am still running the aftermarket 90 degree gearbox and it's working good, but eventually I will reisntall the OEM one and keep this for spare.



Plastic Bushings 070 & 030:


SS Washer:

 

[Doug Vee]

Yes, the deck height adjustment is not very convenient. At least you have pins. Mine has spacers. Not sure if pins could be retrofitted or not. As far as the gauge wheels go, I hear that some people foam fill them. Not sure if that is a good idea or not. So far mine seem to not be a problem.

The only sound comments I have received are that it the machine is really quiet...at least compared to the 24 HP Briggs at WOT, and the high lift blades howling.

Doug

I have come to realize a few things about these “F type” mowers (all brands of them, not just Kubota) compared to a zero turn:
They are not as fast, by a long shot.
They are not quite as maneuverable
They do not have an easily adjustable deck
They are more complicated to fix
They are more expensive to buy

Dude,

I would agree with your statements concerning the "F" machines vs the ZT's. I guess in my case, I traded the speed and maneuverability of the ZT for the more comfortable ride provided by the "F". The longer wheelbase and the larger wheel diameters make a big difference in my rough yard.

I very much appreciate your comments.

Doug

 

[Doug Vee]

Doug,
Glad to see another "local" F3060 owner and I hope my suggestions below will be helpful.


Your question 1.

• I got three SS spacers, in order to be able to use blades with 1-1/8" mounting holes. Been running Gator G6 Mulcher Blades 396-814 for one year with those. You will have many more choices with these spacers in place. I may go back to the OEM 70050-94622 blades next time just for comparison.

Question 2.

• Our property is leveled enough that 4x4 is not really needed so I removed the rear drive shaft and have not noticed any grass stressing due to mower turning around, however it's obviously best to avoid "full lock turns" as much as you can and drive in big circles. Bigger the better. (I think F3060 has something similar to AWD when the shaft is in place) Our Grasshopper mower has bar tires and it's obvious to see the wear those cause when the ground is wet.

Question3.

• Have you checked the 90 degree gearbox oil level? I switched to synthetic gear oil.

Question 4.

• Check the steering for any slack, including the "king pin" plastic bushings 070 seen below. Once all good, double check the rear wheel toe-in.

Question 5.

• In my mower the belt had to be flipped on it's back in order to slide out in-between the gearbox lower pulley & mower deck metal. IE the belt was or is wider than "taller" as far as I recall. In any case, it came out after flipping it 90 degrees. The pulley can be moved slightly up on the shaft, but in order to do so you need to un-mount the 90 degree gearbox.

Here is a thread I started little over year ago regarding the 90 degree gearbox in my 1997 F3060 mower.

90 Degree Bevel Gearbox on Kubota F3060 - 72" Rear Discharge Deck

I am still running the aftermarket 90 degree gearbox and it's working good, but eventually I will reisntall the OEM one and keep this for spare.



Plastic Bushings 070 & 030:
View attachment 758391

SS Washer:
View attachment 758389

Arto,

Thanks for the reply. I noted that you and I are in the same general neck of the woods also.

Concerning the spacers, I was kind of thinking that was going to be my only recourse, but wanted to confirm
that there are no readily available blades with 7/8" shaft holes. I will look into finding some and then get the high lift blades I think I want.

About the rear driveshaft, I will have a look at that as a possibility. I would usually want the 4x4 available, because of one area of my yard is pretty steep. I have not mowed it for a couple of weeks due to there is nothing but dandelions to mow, and since it is somewhat over the hill from my line of sight, I let that area languish this time of year.

Gearbox level is good. I will look into changing out the Dino oil for synthetic this winter.

Concerning the steering, I will look for play at the #70 bushings. I do note that the rear tires seem to have a lot of positive camber, in other words, the tops lean out. The outer edges of the tires are worn more than the inner edges. It seems like worn bushings would lean the wheels the other way?

The belt removal is still stumping me. I have already tried flipping the belt 90 degrees, but the belt would not clear. I cut a piece of wood to the same cross section dimension of the belt to get a better idea what the problem was. The block cleared the botton of the sheave collet, but not the bolt heads that secure the collet. The only thing I can think of is that when the sheave was installed on the shaft, it was not slid on far enough before the collet was tightened. I am pretty sure I can just loosen the four bolts that secure the gearbox housing and be able to change the belt, it's just that it would be much nicer to not have to do that. This winter I work to correct that condition.

Anyhow, thanks again for the reply, I appreciate it.

Doug

 

[arto98607]

Doug,

If you leave the engine idling and stand on the right hand side of rear axle while looking at the 060 (arm knuckle) & tie-rod ends while turning the steering wheel slightly back and forth, you will see it there is excess slack in the plastic bushings etc.

It should all be pretty tight.

If doing this alone, the operator seat safety switch may have to be jumpered temporarily.

 

[Brown Dog]

… I guess in my case, I traded the speed and maneuverability of the ZT for the more comfortable ride provided by the "F". The longer wheelbase and the larger wheel diameters make a big difference in my rough yard ...

Doug

How does the small tire diameter deck wheels do on your rough ground ?

I love my ZD1511 but it’ll absolutely beat your brains out on my rough farm ground mowing 8-9hrs per week & I don’t go fast.

 

[Hay Dude]

Since I have both a ZD331 and a F3680, I actually think the ZD331 rides a little better. Both are rough on the posterior, but neither of mine have what I would call a really comfortable seat. The little rear tires on the F really magnify the bumps in lawns.
It’s the price you pay for traction.
The front mowing deck tires on the F don’t really transfer much “shock” to the operator since the front deck rolls in front of the machine more independently than the hanging mower deck on the ZD331 zero turn.

 

[Doug Vee]

How does the small tire diameter deck wheels do on your rough ground ?

I love my ZD1511 but it’ll absolutely beat your brains out on my rough farm ground mowing 8-9hrs per week & I don’t go fast.

BD,

They don't seem to complain too much. It has been a few months since I sold my ZT, but the front caster wheels seemed pretty close to the same diameter as the deck casters are on the F machine. I am pretty sure the wheel assemblies on my old ZT were more stout than the deck casters on the F machine though.

Doug.

 

[Doug Vee]

Doug,

If you leave the engine idling and stand on the right hand side of rear axle while looking at the 060 (arm knuckle) & tie-rod ends while turning the steering wheel slightly back and forth, you will see it there is excess slack in the plastic bushings etc.

It should all be pretty tight.

If doing this alone, the operator seat safety switch may have to be jumpered temporarily.


View attachment 758447

Arto,

I will be sure to check that this week when I have the mower out again. Thanks for the tip.

Doug

 

[m7040]

I added a Grammer self contained air suspension seat to the ZD331 and cast iron weights in the rear and that gives a fairly comfortable ride and added traction

 

[m7040]

Pic of the Grammer seat