F-Series Hydro Leak

   / F-Series Hydro Leak #1  

Rip

Platinum Member
Joined
Jan 26, 2004
Messages
668
Location
NW Tasmania, Australia
Tractor
Kubota F-2880 & F-3680
My F-3680 has had a minor hydro leak that just became major from the swash plate / trunnion shaft left (solid) side support cover plate. Would be simple fix, but tight access/visibility inside the frame. Has anyone dealt with this in F-series or other B/BX machines and have any tips??

I still have my F-2880 w/60" deck which has been working fine for 11 years, but came across a local 3680 with 72" deck at a "too-good-to-pass-up" price (had been traded in to the JD dealer!) so added it to my small fleet. Did have to fully reweld the deck itself, but the tractor was in pretty good nick. Mowing now almost 20% faster!! Sooner to BEER time!

Cheers, Rip in Tasmania
 
   / F-Series Hydro Leak #2  
Hi Rip,

Couple of years ago I took the HST, speed range selector & front axle apart on my F3060, which should be very similar design as F3680

Kubota F3060 HST / 2-Speed Range Selector Housing Oil Leak

It's nearly impossible to access much of it without removing the frame etc. which is fair bit of work involved.


IMG_5348.JPG IMG_5346.JPGIMG_5453.JPGIMG_5495.JPG


Do you have any photos of the area in question?



PS.
I also took the HST apart in order to replace the cradle bearings just to be sure they will be new (Item 050 below), since the speed change treadle was little stiff to adjust.

The design of later model F3060 of this particular detail is different.


D01501_HST_Components.jpg
 
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   / F-Series Hydro Leak
  • Thread Starter
#3  
Thanks Arto, I am either going to do this "in place" or send to the dealer. Looks tight but doable with the (un)appropriate cursing to move it along. My leak is on left side, middle of hydro section (opposite the forward/reverse shaft, which is on the right). Looks like you had a major job on your machine!
 
   / F-Series Hydro Leak #4  
F3060 has threaded removable plug (item 220 above) for the left hand end bearing of the forward/reverse shaft.
I did not remove it, but it must have seal of some type (aluminum or copper?).

Like mentioned above, the swash plate design has changed - this is the F3680 HST housing left side view:

F3680 HST.png


And here is the inside, showing an O-ring seal for item 4:

F3680 HST II.png

You can get detailed F3680 parts drawings for example from Messicks site.

Kubota F3680 (4WD TRACTOR W/FOLDABLE ROPS) Parts
 
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   / F-Series Hydro Leak
  • Thread Starter
#5  
Thanks Arto, I have the Workshop manual and use the Messicks parts lists all the time... both quite helpful. The B cover is circlip retained, not threaded and is O-ring sealed. Figure the O-ring gone bad, but getting to it in-frame is the tricky part. The side cover plate is also the bearing support for the swash plate/trunnion shaft and I may replace it with the O-ring as I do not want to do this job twice!

Am diving into YT videos as well, looking for what is involved.... will see. Rip
 
   / F-Series Hydro Leak #6  
Rip,
Good to hear, sounds like you have it figured out.

Yes, the swash plate design was changed and newer model F3060 also have the same design as you have, IE no 'slide' cradle bearings or threaded plug.

It's a challenge to get to it without some disassembly for sure!

Thinking.jpg

Cheers
 
   / F-Series Hydro Leak #7  
Well. It's good
 
   / F-Series Hydro Leak #8  
Thanks Arto, I have the Workshop manual and use the Messicks parts lists all the time... both quite helpful. The B cover is circlip retained, not threaded and is O-ring sealed. Figure the O-ring gone bad, but getting to it in-frame is the tricky part. The side cover plate is also the bearing support for the swash plate/trunnion shaft and I may replace it with the O-ring as I do not want to do this job twice!

Am diving into YT videos as well, looking for what is involved.... will see. Rip


Please keep us posted whether you are able to access & replace the O-ring without much disassembly?
 
   / F-Series Hydro Leak
  • Thread Starter
#9  
I gave up planning to deal with this myself.... just not up to doing all that seems necessary at my age (73), even though just a lot of bolts to remove ROPS, seat, floor pan, fuel tank, inner side frame, etc, etc before getting access to the hydro side cap to replace one O-ring! Had dealer field tech look at it and order parts.... will take to shop and will let you know if they do all the above or have some tricks up their sleeve! Lot of these machines around for many years so has to have happened before.

Cheers, Rip
 
   / F-Series Hydro Leak #10  
My F3680 just needed the motor mounts replaced. 1300 hours seems kinda low for this repair.
 
 
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