L48 split for HST repair

   / L48 split for HST repair #51  
Not sure I see parts" XX". In fact, I'm afraid I'll need to go to the parts book to get the geometry straight in my mind. I do seem to remember that even when the front propeller shaft ran from tranny to front diff in a tube outside the cases there were seals involved - and that it wasn't unusual to see them leaking on any make of 4wd tractor. I wonder why the same shaft doesn't leak on cars as much?

Hmmm.....Is that some sort of gray RTV sealing compound that I see on the case face when I blow up the picture? What did you use there?
rScotty
 

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   / L48 split for HST repair
  • Thread Starter
#52  
Hi rScotty -you're quick. Just edited to include parts 9, 12, & 13, and two drawings from the WSM. The sealant is the old stuff not cleaned off yet. I used Three Bond 1027F on this joint - and Permatex Ultra Grey on the HST port block & clutch housing.
 
   / L48 split for HST repair #53  
Back on reassembling the L48, an aspect I wanted to cover was replacing the seals on the front propeller shaft. When Kubota relocated it inside instead of running underneath, a transmission oil seal was added at the clutch housing. These seals have been prone to leaking and have been redesigned. Whenever a machine is apart the seals should be replaced with the new version.

With such a long driveshaft, it seems that damaging seals would be easy. Careful alignment and patience are certainly necessary. Looks like you have both, Dick.

On the JD 4300s I split, there was a helpful side hatch on the tunnel to get your hand in there to align all 3 shafts.

I have only split 7 or 8 tractors, and the hardest driveshaft alignment I did was doing a double dry clutch on an old Kubota L2550DT. You had to turn both clutch discs to go on a single spline shaft.
 
   / L48 split for HST repair
  • Thread Starter
#54  
This is an update to report the L48 HST repair is performing fine since replacing its cradle bearings about 6 months ago. I've used it with a grapple quite a bit, moving cords of firewood and saw logs. Machine works great and I've become an HST fan, really appreciating its convenient control. No leaks, no drips, no errors, and no new issues :thumbsup:

(scroll up - or click for the whole saga here).
 
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   / L48 split for HST repair #56  
Very helpful thread. Thanks for the update.
 
   / L48 split for HST repair
  • Thread Starter
#57  
Hello again group, I'm back with an another update on the L48 HST fix. Tractor is still performing very well - no issues of any kind except a funny one - the vent in the fuel cap was plugged with bug dust so the fuel lift pump collapsed the plastic tank like a shrunken head. With some heat and compressed air it pushed back into original shape.

My original plan was to fix this tractor and sell it - but it's way too handy to part with :thumbsup:
Dick B
 
   / L48 split for HST repair #58  
Good to hear the tractor is doing well for you. Hard to believe the lift pump had enough power to collapse the tank. Always something new!
 
   / L48 split for HST repair #59  
Have had many tractors over many decades. Pros and cons of any. Now just two Kubota TLBs that best fit our needs. Incredible, versatile, and strong machines. It all started by chance with a used Kubota’s first dedicated TLB the B20 thirty years ago. Several times almost bought a L48 until finding a M59 in my budget.
 
   / L48 split for HST repair #60  

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